Ribbon Communications Inc - Ordinary Shares 10-Q 31 Oct 13 2013 Q3 Quarterly report Financial data

Document_and_Entity_Informatio

Document and Entity Information	9 Months Ended
	Sep. 27, 2013	Oct. 18, 2013
Document And Entity Information	'	'
Entity Registrant Name	'SONUS NETWORKS INC	'
Entity Central Index Key	'0001105472	'
Current Fiscal Year End Date	'--12-31	'
Entity Filer Category	'Accelerated Filer	'
Document Type	'10-Q	'
Document Period End Date	27-Sep-13	'
Document Fiscal Year Focus	'2013	'
Document Fiscal Period Focus	'Q3	'
Amendment Flag	'false	'
Entity Common Stock, Shares Outstanding	'	273,495,101
Entity Well-known Seasoned Issuer	'No	'
Entity Voluntary Filers	'No	'
Entity Current Reporting Status	'Yes	'

Consolidated_Balance_Sheets

Consolidated Balance Sheets (USD $)	Sep. 27, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified
Current assets:	'	'
Cash and cash equivalents	$72,385	$88,004
Marketable securities	128,177	161,905
Accounts receivable, net of allowance for doubtful accounts of $364 at September 27, 2013 and $0 at December 31, 2012	52,479	68,728
Inventory	22,058	25,614
Deferred income taxes	632	686
Other current assets	14,450	16,520
Total current assets	290,181	361,457
Property and equipment, net	18,756	23,767
Intangible assets, net	11,177	15,237
Goodwill	32,379	32,379
Investments	66,889	29,698
Deferred income taxes	954	1,011
Other assets	7,616	7,191
Total assets	427,952	470,740
Current liabilities:	'	'
Accounts payable	16,001	10,643
Accrued expenses	25,967	26,212
Current portion of deferred revenue	36,556	37,094
Current portion of long-term liabilities	572	763
Total current liabilities	79,096	74,712
Deferred revenue	10,322	11,647
Deferred income taxes	790	249
Convertible subordinated note	2,380	2,380
Other long-term liabilities	4,689	5,706
Total liabilities	97,277	94,694
Commitments and contingencies (Note 16)	'	'
Stockholders' equity:	'	'
Preferred stock, $0.01 par value per share; 5,000,000 shares authorized, none issued and outstanding	0	0
Common stock, $0.001 par value per share; 600,000,000 shares authorized; 273,305,861 shares issued and outstanding at September 27, 2013; 280,963,298 shares issued and outstanding at December 31, 2012	273	281
Additional paid-in capital	1,299,029	1,321,385
Accumulated deficit	-974,764	-952,373
Accumulated other comprehensive income	6,137	6,753
Total stockholders' equity	330,675	376,046
Total liabilities and stockholders' equity	$427,952	$470,740

Consolidated_Balance_Sheets_Pa

Consolidated Balance Sheets (Parenthetical) (USD $)	Sep. 27, 2013	Dec. 31, 2012
In Thousands, except Share data, unless otherwise specified
Statement of Financial Position [Abstract]	'	'
Allowance for doubtful accounts	$364	$0
Preferred stock, par value (in dollars per share)	$0.01	$0.01
Preferred stock, shares authorized	5,000,000	5,000,000
Preferred stock, shares issued	0	0
Preferred stock, shares outstanding	0	0
Common stock, par value (in dollars per share)	$0.00	$0.00
Common stock, shares authorized	600,000,000	600,000,000
Common stock, shares issued	273,305,861	280,963,298
Common stock, shares outstanding	273,305,861	280,963,298

Consolidated_Statements_of_Ope

Consolidated Statements of Operations (USD $)	3 Months Ended		9 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Sep. 27, 2013	Sep. 28, 2012	Sep. 27, 2013	Sep. 28, 2012
Revenue:	'	'	'	'
Product	$40,712	$33,520	$121,447	$107,517
Service	27,387	23,529	79,133	71,481
Total revenue	68,099	57,049	200,580	178,998
Cost of revenue:	'	'	'	'
Product	15,415	11,768	42,844	31,988
Service	10,420	12,839	33,662	40,019
Total cost of revenue	25,835	24,607	76,506	72,007
Gross profit	42,264	32,442	124,074	106,991
Operating expenses:	'	'	'	'
Research and development	16,566	15,612	52,086	51,094
Sales and marketing	18,291	17,613	58,596	56,339
General and administrative	9,178	7,939	29,621	25,302
Acquisition-related	0	4,090	0	5,057
Restructuring	1,140	1,992	4,787	1,992
Total operating expenses	45,175	47,246	145,090	139,784
Loss from operations	-2,911	-14,804	-21,016	-32,793
Interest income, net	61	20	289	457
Other income, net	-1	-2	2	-2
Loss before income taxes	-2,851	-14,786	-20,725	-32,338
Income tax provision	-922	-833	-1,666	-1,444
Net loss	($3,773)	($15,619)	($22,391)	($33,782)
Loss per share	'	'	'	'
Basic (in dollars per share)	($0.01)	($0.06)	($0.08)	($0.12)
Diluted (in dollars per share)	($0.01)	($0.06)	($0.08)	($0.12)
Shares used to compute loss per share:	'	'	'	'
Basic (in shares)	279,209	280,145	281,041	279,854
Diluted (in shares)	279,209	280,145	281,041	279,854

Consolidated_Statements_of_Com

Consolidated Statements of Comprehensive Loss (USD $)	3 Months Ended		9 Months Ended
In Thousands, unless otherwise specified	Sep. 27, 2013	Sep. 28, 2012	Sep. 27, 2013	Sep. 28, 2012
Statement of Other Comprehensive Income [Abstract]	'	'	'	'
Net loss	($3,773)	($15,619)	($22,391)	($33,782)
Other comprehensive income (loss), net of tax:	'	'	'	'
Foreign currency translation adjustments	-77	119	-532	-76
Unrealized gain (loss) on available-for sale marketable securities, net of tax	188	127	-84	24
Other comprehensive income (loss), net of tax	111	246	-616	-52
Comprehensive loss, net of tax	($3,662)	($15,373)	($23,007)	($33,834)

Consolidated_Statements_of_Cas

Consolidated Statements of Cash Flows (USD $)	9 Months Ended
In Thousands, unless otherwise specified	Sep. 27, 2013	Sep. 28, 2012
Cash flows from operating activities:	'	'
Net loss	($22,391)	($33,782)
Adjustments to reconcile net loss to cash flows provided by (used in) operating activities:	'	'
Depreciation and amortization of property and equipment	9,591	9,081
Amortization of intangible assets	3,460	904
Impairment of intangible assets	600	0
Stock-based compensation	13,137	6,540
Loss on disposal of property and equipment	23	23
Deferred income taxes	541	0
Changes in operating assets and liabilities:	'	'
Accounts receivable	15,744	13,020
Inventory	3,294	-3,868
Other operating assets	5,126	-4,998
Accounts payable	5,134	-1,753
Accrued expenses and other long-term liabilities	-2,061	-3,625
Deferred revenue	-1,664	-9,624
Net cash provided by (used in) operating activities	30,534	-28,082
Cash flows from investing activities:	'	'
Purchases of property and equipment	-4,498	-7,792
Business acquisition, net of cash acquired	0	-35,508
Purchases of marketable securities	-182,534	-139,917
Maturities of marketable securities	175,887	200,380
Net cash (used in) provided by investing activities	-11,145	17,163
Cash flows from financing activities:	'	'
Proceeds from sale of common stock in connection with employee stock purchase plan	1,888	1,693
Proceeds from exercise of stock options	2,393	151
Payment of tax withholding obligations related to net share settlements of restricted stock awards	-1,240	-169
Repurchase of common stock	-37,340	0
Principal payments of capital lease obligations	-91	-87
Settlement of redeemable convertible subordinated debentures	0	23,704
Net cash used in financing activities	-34,390	-22,116
Effect of exchange rate changes on cash and cash equivalents	-618	192
Net decrease in cash and cash equivalents	-15,619	-32,843
Cash and cash equivalents, beginning of year	88,004	105,451
Cash and cash equivalents, end of period	72,385	'
Supplemental disclosure of cash flow information:	'	'
Interest paid	49	638
Income taxes paid	1,391	1,958
Income tax refunds received	117	42
Supplemental disclosure of non-cash investing activities:	'	'
Capital expenditures incurred, but not yet paid	467	861
Property and equipment acquired under operating lease	0	40
Business acquisition purchase consideration - assumed equity awards	$0	$892

BASIS_OF_PRESENTATION

BASIS OF PRESENTATION	9 Months Ended
	Sep. 27, 2013
Accounting Policies [Abstract]	'
BASIS OF PRESENTATION	'
	BASIS OF PRESENTATION
	Business
	Sonus Networks, Inc. (“Sonus” or the “Company”) was incorporated in 1997 and is a leading provider of networked solutions for communications service providers (e.g., telecommunications, wireless and cable service providers) and enterprises to help them advance, protect and unify their communications and improve collaboration. Sonus' products include session border controllers, Session Initiation Protocol ("SIP") session management servers, Voice over IP ("VoIP"), switches, SIP application servers, multiprotocol signaling gateways and network analytics tools. Sonus' solutions address the need for communications service providers and enterprises to seamlessly link and leverage multivendor, multiprotocol communications systems and applications across their networks, around the world and in a rapidly changing ecosystem of IP-enabled devices such as smartphones and tablets.
	The Company's target customers comprise both communications service providers and enterprises utilizing both direct and indirect sales channels. Customers and prospective customers in the service provider space are traditional and emerging communications providers, including long distance carriers, local exchange carriers, Internet service providers, wireless operators, cable operators, international telephone companies and carriers that provide services to other carriers. Enterprise customers and target enterprise customers include financial institutions, retailers, state and local governments, and other multinational corporations. The Company collaborates with its customers to identify and develop new, advanced services and applications that can help to reduce costs, improve productivity and generate new revenue.
	Basis of Presentation
	In the opinion of management, the accompanying unaudited condensed consolidated financial statements include all adjustments, consisting only of normal recurring items, necessary for their fair presentation with accounting principles generally accepted in the United States of America ("GAAP") and with the rules and regulations of the U.S. Securities and Exchange Commission ("SEC").
	Interim results are not necessarily indicative of results for a full year or any future interim period. The information included in this Quarterly Report on Form 10-Q should be read in conjunction with the Company's Annual Report on Form 10-K for the year ended December 31, 2012 ("Annual Report") filed with the SEC on March 6, 2013.
	On August 24, 2012, the Company completed the acquisition of Network Equipment Technologies, Inc. (“NET”). The financial results of NET are included in the Company's condensed consolidated financial statements for the three and nine months ended September 27, 2013 and for the three and nine months ended September 28, 2012 for the period subsequent to August 24, 2012.
	The Company reported acquisition-related expenses of approximately $967,000 as a component of general and administrative expenses in its Quarterly Report on Form 10-Q for the quarter ended June 29, 2012. The Company is now separately reporting this amount as acquisition-related expenses in the condensed statements of operations included herein.
	Significant Accounting Policies
	The Company's significant accounting policies are disclosed in Note 2 to the Consolidated Financial Statements included in the Company's Annual Report. There were no material changes to the significant accounting policies during the three or nine months ended September 27, 2013.
	Principles of Consolidation
	The condensed consolidated financial statements include the accounts of Sonus and its wholly-owned subsidiaries. Intercompany transactions and balances have been eliminated in consolidation.
	Use of Estimates and Judgments
	The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the reporting periods. Significant estimates and judgments relied upon in preparing these consolidated financial statements include accounting for business combinations, revenue recognition for multiple element arrangements, inventory valuations, assumptions used to determine the fair value of stock-based compensation, intangible assets and goodwill valuations, including impairments, legal contingencies and recoverability of Sonus' net deferred tax assets and the related valuation allowances. Sonus regularly assesses these estimates and records changes in estimates in the period in which they become known. Sonus bases its estimates on historical experience and various other assumptions that it believes to be reasonable under the circumstances. Actual results could differ from those estimates.
	Fair Value of Financial Instruments
	The carrying amounts of the Company's financial instruments, which include cash equivalents, marketable securities, investments, accounts receivable, accounts payable, convertible subordinated debt and other long-term liabilities, approximate their fair values.
	Operating Segments
	The Company operates in a single segment. Operating segments are identified as components of an enterprise about which separate discrete financial information is available for evaluation by the chief operating decision maker in making decisions regarding resource allocation and assessing performance. To date, the chief operating decision maker has made such decisions and assessed performance at the company level, as one segment. The Company's chief operating decision maker is its President and Chief Executive Officer.
	Recent Accounting Pronouncements
	On July 18, 2013, the Financial Accounting Standards Board ("FASB") issued Accounting Standards Update ("ASU") 2013-11, Presentation of a Liability for an Unrecognized Tax Benefit When a Net Operating Loss Carryforward or Tax Credit Carryforward Exists ("ASU 2013-11"), which provides guidance on financial statement presentation of an unrecognized tax benefit when a net operating loss ("NOL") carryforward, a similar tax loss or a tax credit carryforward exists. The FASB's objective in issuing ASU 2013-11 is to eliminate diversity in practice resulting from a lack of guidance on this topic in current GAAP. ASU 2013-11 requires that an entity present an unrecognized tax benefit, or a portion of an unrecognized tax benefit, in the financial statements as a reduction to a deferred tax asset for an NOL carryforward, a similar tax loss or a tax credit unless certain conditions exist. ASU 2013-11 is effective for the Company beginning January 1, 2014. The Company does not expect the adoption of ASU 2013-11 to have an impact on its consolidated financial statements, as the Company currently applies the methodology prescribed by ASU 2013-11.
	On March 4, 2013, the FASB issued ASU 2013-05, Foreign Currency Matters (Topic 830) - Parent's Accounting for the Cumulative Translation Adjustment upon Derecognition of Certain Subsidiaries or Groups of Assets within a Foreign Entity or of an Investment in a Foreign Entity ("ASU 2013-05"), which indicates that the entire amount of a cumulative translation adjustment ("CTA") related to an entity's investment in a foreign entity should be released when there has been either: (a) a sale of a subsidiary or group of net assets within a foreign entity and the sale represents the substantially complete liquidation of the investment in a foreign entity; (b) the loss of a controlling financial interest in an investment in a foreign entity (i.e., the foreign entity is deconsolidated); or (c) the step acquisition of a foreign entity (i.e., when the accounting for an entity has changed from applying the equity method for an investment in a foreign entity to consolidating the foreign entity). ASU 2013-05 does not change the requirement to release a pro rata portion of the CTA of the foreign entity into earnings for a partial sale of an equity method investment in a foreign entity. ASU 2013-05 is effective for the Company beginning January 1, 2014, although early adoption is permitted. The Company does not expect the adoption of ASU 2013-05 to have a material impact on its consolidated financial statements.
	On February 5, 2013, the FASB issued ASU 2013-02, Comprehensive Income (Topic 220): Reporting of Amounts Reclassified Out of Accumulated Other Comprehensive Income ("ASU 2013-02"), which requires entities to disclose changes in accumulated other comprehensive income balances by component (i.e., unrealized gains or losses on available-for-sale securities or foreign-currency items) and significant items reclassified out of accumulated other comprehensive income by component either on the face of the income statement or as a separate footnote to the financial statements. ASU 2013-02 does not change the current requirements for interim financial statement reporting of comprehensive income. ASU 2013-02 became effective for the Company on January 1, 2013. The Company does not have significant items reclassified out of accumulated other comprehensive income and accordingly, the adoption of ASU 2013-02 did not impact the Company's condensed consolidated financial statements.

ACQUISITION_OF_NET

ACQUISITION OF NET	9 Months Ended
	Sep. 27, 2013
Business Combinations [Abstract]	'
ACQUISITION OF NET	'
	ACQUISITION OF NET
	On August 24, 2012 (the “NET Acquisition Date”), the Company acquired all of the outstanding common stock of NET for cash consideration of $41.5 million, or $1.35 per share of NET common stock. The acquisition was effected through a merger of a wholly-owned subsidiary of the Company into NET, with NET surviving the merger as a wholly-owned subsidiary of the Company. NET is a provider of networking equipment focused on secure real-time communications for Unified Communications ("UC"), SIP trunking, enterprise mobility and IP-based multi-service networking. The Company acquired NET to enhance its position as an enabler of cloud-based UC. The acquisition of NET expands the Company's portfolio of Session Border Controller (“SBC”) solutions for enterprise customers and brings engineering resources, broader channel capability and a broad U.S. federal government installed base to leverage into SIP-enabled platforms.
	As of August 24, 2013, the valuation of acquired assets, identifiable intangible assets, uncertain tax liabilities and certain accrued liabilities had been finalized. Based on new information gathered about facts and circumstances that existed as of the NET Acquisition Date related to the valuation of certain acquired assets and assumed liabilities, the Company finalized its valuations of assets acquired and liabilities assumed. The Company recorded retrospective adjustments as of December 31, 2012, which resulted in a net decrease to goodwill of $1.4 million, a net increase to other current assets of $0.9 million and a net decrease to current liabilities of $0.5 million as set forth in the table below. The adjustments have been retrospectively applied to the December 31, 2012 balance sheet; however, these adjustments had no impact on either the condensed consolidated statements of operations or the condensed consolidated statements of cash flows.
	During the second quarter of fiscal 2013, the Company made an election under Section 338(g) of the Internal Revenue Code to have the NET transaction treated as an asset acquisition (i.e., a taxable transaction) with the goodwill being deductible for tax purposes over 15 years.
	A summary of the allocation of the purchase consideration for NET is as follows (in thousands):
	Fair value of consideration transferred:
	Cash, net of cash acquired	$	35,508
	Fair value of equity awards assumed	892
	Fair value of total consideration	$	36,400
	Fair value of assets acquired and liabilities assumed:
	Marketable securities	$	5,359
	Deferred income taxes	681
	Other current assets	13,388
	Property and equipment	4,694
	Noncurrent investments	10,167
	Intangible assets	16,810
	Goodwill	27,317
	Other noncurrent assets	1,843
	Current liabilities	(9,350		)
	Debt	(34,208		)
	Other long-term liabilities	(301		)
		$	36,400
	The valuation of the acquired intangible assets is inherently subjective and relies on significant unobservable inputs. The Company used an income approach to value the acquired customer relationships and developed technology intangible assets. The valuation for each of these intangible assets was based on estimated projections of expected cash flows to be generated by the assets, discounted to the present value at discount rates commensurate with perceived risk. The valuation assumptions take into consideration the Company's estimates of contract renewal, technology attrition and revenue growth projections. The Company is amortizing the identifiable intangible assets in relation to the expected cash flows from the individual intangible assets over their respective useful lives (see Note 6).
	Pro Forma Results
	The following unaudited pro forma information presents the condensed combined results of operations of the Company and NET for the three and nine months ended September 28, 2012 as if the acquisition of NET had been completed on January 1, 2011, with adjustments to give effect to pro forma events that are directly attributable to the acquisition. These pro forma adjustments include a reduction to historical NET revenue for the fair value adjustment related to assumed deferred revenue, an increase in amortization expense for the acquired identifiable intangible assets and decreases in historical NET interest expense and the Company's historical interest income reflecting the extinguishment of certain of NET's debt as a result of the acquisition. Subsequent to the filing of the Company's Quarterly Report on Form 10-Q for the quarter ended September 28, 2012, the Company refined the amounts and attribution of certain expenses related to the acquisition and the related purchase accounting and accordingly, the pro forma information below has been revised.
	The unaudited pro forma results do not reflect any operating efficiencies or potential cost savings which may result from the consolidation of the operations of the Company and NET. Accordingly, these unaudited pro forma results are presented for illustrative purposes and are not intended to represent or be indicative of the actual results of operations of the combined companies that would have been achieved had the acquisition occurred as of January 1, 2011, nor are they intended to represent or be indicative of future results of operations (in thousands, except per share amount):
		Three months ended			Nine months ended
		September 28, 2012			September 28, 2012
	Revenue	$	63,369		$	207,878
	Net loss	$	(13,496	)	$	(48,765	)
	Loss per share	$	(0.05	)	$	(0.17	)
	Acquisition-Related Expenses
	Acquisition-related expenses include those expenses related to the acquisition that would otherwise not have been incurred by the Company. These expenses include professional and services fees, such as legal, audit, consulting, paying agent and other fees, and expenses related to cash payments to former NET executives under their NET change of control agreements.
	The components of acquisition-related costs included in the Company's results of operations for the three and nine months ended September 28, 2012 are as follows (in thousands):
		Three months ended			Nine months ended
		September 28, 2012			September 28, 2012
	Professional and services fees	$	2,048		$	3,015
	Change of control agreements	2,042			2,042
		$	4,090		$	5,057
	The Company did not record any acquisition-related expenses in either the three or nine months ended September 27, 2013.

EARNINGS_LOSS_PER_SHARE

EARNINGS (LOSS) PER SHARE	9 Months Ended
	Sep. 27, 2013
Earnings Per Share [Abstract]	'
EARNINGS (LOSS) PER SHARE	'
	EARNINGS (LOSS) PER SHARE
	Basic earnings (loss) per share is computed by dividing net income (loss) by the weighted average number of shares outstanding during the period. For periods in which the Company reports net income, diluted net income per share is determined by using the weighted average number of common and dilutive common equivalent shares outstanding during the period unless the effect is antidilutive.
	The calculations of shares used to compute basic and diluted loss per share are as follows (in thousands):
		Three months ended		Nine months ended
		September 27,	September 28,	September 27,	September 28,
		2013	2012	2013	2012
	Weighted average shares outstanding—basic	279,209	280,145	281,041	279,854
	Potential dilutive common shares	—	—	—	—
	Weighted average shares outstanding—diluted	279,209	280,145	281,041	279,854
	Options to purchase the Company's common stock, unvested shares of restricted stock and unvested performance-based stock awards for which the performance conditions have been satisfied aggregating 35.9 million shares for the three and nine months ended September 27, 2013 have not been included in the computation of diluted loss per share because their effect would have been antidilutive. Options to purchase the Company's common stock and unvested shares of restricted stock aggregating 27.2 million shares for the three and nine months ended September 28, 2012 have not been included in the computation of diluted loss per share because their effect would have been antidilutive.

CASH_EQUIVALENTS_MARKETABLE_SE

CASH EQUIVALENTS, MARKETABLE SECURITIES AND INVESTMENTS	9 Months Ended
	Sep. 27, 2013
Investments, All Other Investments [Abstract]	'
CASH EQUIVALENTS, MARKETABLE SECURITIES AND INVESTMENTS	'
	CASH EQUIVALENTS, MARKETABLE SECURITIES AND INVESTMENTS
	The Company invests in debt and equity instruments, primarily U.S. government-backed, municipal and corporate obligations, which management believes to be high quality (investment grade) credit instruments.
	During the nine months ended September 27, 2013 and September 28, 2012, the Company did not sell any of its available-for-sale securities and accordingly, no such gains or losses were realized.
	Marketable securities and investments with continuous unrealized losses for one year or greater at September 27, 2013 were nominal. Since the Company does not intend to sell these securities and does not believe it will be required to sell any securities before they recover in value, it does not believe these declines are other-than-temporary.
	On a quarterly basis, the Company reviews its marketable securities and investments to determine if there have been any events that could create a credit impairment. The increase in unrealized losses in the current year period primarily relates to the recent increase in interest rates. However, since the Company's entire investment portfolio has investment grade ratings with no indication of credit loss, the Company believes it will recover the entire amortized cost basis of these securities and does not believe these unrealized losses are other-than-temporary. Accordingly, the Company does not believe that any impairment existed with its current holdings at September 27, 2013.
	The amortized cost, gross unrealized gains and losses and fair value of the Company's marketable debt and equity securities and investments at September 27, 2013 and December 31, 2012 were comprised of the following (in thousands):
		27-Sep-13
		Amortized		Unrealized		Unrealized			Fair
		cost		gains		losses			value
	Cash equivalents	$	33,110	$	—	$	—		$	33,110
	Marketable securities
	U.S. government agency notes	$	47,606	$	30	$	—		$	47,636
	Corporate debt securities	65,241		24		(20		)	65,245
	Commercial paper	11,240		4		—			11,244
	Certificates of deposit	4,050		3		(1		)	4,052
		$	128,137	$	61	$	(21	)	$	128,177
	Investments
	U.S. government agency notes	$	20,471	$	8	$	(3	)	$	20,476
	Foreign government notes	1,250		—		(1		)	1,249
	Corporate debt securities	45,188		16		(40		)	45,164
		$	66,909	$	24	$	(44	)	$	66,889
		31-Dec-12
		Amortized		Unrealized		Unrealized			Fair
		cost		gains		losses			value
	Cash equivalents	$	69,389	$	—	$	—		$	69,389
	Marketable securities
	U.S. government agency notes	$	53,646	$	22	$	—		$	53,668
	Foreign government notes	2,000		1		—			2,001
	Corporate debt securities	84,047		34		(5		)	84,076
	Commercial paper	7,492		5		—			7,497
	Certificates of deposit	14,650		13		—			14,663
		$	161,835	$	75	$	(5	)	$	161,905
	Investments
	U.S. government agency notes	$	19,358	$	20	$	—		$	19,378
	Corporate debt securities	10,306		20		(6		)	10,320
		$	29,664	$	40	$	(6	)	$	29,698
	The Company's available-for-sale debt securities that are classified as Investments in the condensed consolidated balance sheet mature after one year but within two years or less from the balance sheet date.
	Fair Value Hierarchy
	Fair value is the price that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants. As such, fair value is a market-based measurement that should be determined based on assumptions that market participants would use in pricing an asset or a liability. The three-tier fair value hierarchy is based on the level of independent, objective evidence surrounding the inputs used to measure fair value. A financial instrument's categorization within the fair value hierarchy is based upon the lowest level of input that is significant to the fair value measurement. The fair value hierarchy is as follows:
	Level 1. Level 1 applies to assets or liabilities for which there are quoted prices in active markets for identical assets or liabilities.
	Level 2. Level 2 applies to assets or liabilities for which there are inputs that are directly or indirectly observable in the marketplace, such as quoted prices for similar assets or liabilities in active markets or quoted prices for identical assets or liabilities in markets with insufficient volume or infrequent transactions (less active markets).
	Level 3. Level 3 applies to assets or liabilities for which there are unobservable inputs to the valuation methodology that are significant to the measurement of the fair value of the assets or liabilities.
	The following table shows the fair value of the Company's financial assets at September 27, 2013 and December 31, 2012. These financial assets are comprised of the Company's available-for-sale debt and equity securities and reported under the captions Cash and cash equivalents, Marketable securities and Investments in the consolidated balance sheets (in thousands):
				Fair value measurements at
				September 27, 2013 using:
		Total carrying		Quoted prices		Significant other			Significant
		value at		in active		observable			unobservable
		September 27,		markets		inputs			inputs
		2013		(Level 1)		(Level 2)			(Level 3)
	Cash equivalents	$	33,110	$	33,110	$	—		$	—
	Marketable securities
	U.S. government agency notes	$	47,636	$	—	$	47,636		$	—
	Corporate debt securities	65,245		—		65,245			—
	Commercial paper	11,244		—		11,244			—
	Certificates of deposit	4,052		—		4,052			—
		$	128,177	$	—	$	128,177		$	—
	Investments
	U.S. government agency notes	$	20,476	$	—	$	20,476		$	—
	Foreign government notes	1,249		—		1,249			—
	Corporate debt securities	45,164		—		45,164			—
		$	66,889	$	—	$	66,889		$	—
				Fair value measurements at
				December 31, 2012 using:
	Total carrying		Quoted prices		Significant other			Significant
	value at		in active		observable			unobservable
	December 31,		markets		inputs			inputs
	2012		(Level 1)		(Level 2)			(Level 3)
Cash equivalents	$	69,389	$	68,389	$	1,000		$	—
Marketable securities
U.S. government agency notes	$	53,668	$	—	$	53,668		$	—
Foreign government notes	2,001		—		2,001			—
Corporate debt securities	84,076		—		84,076			—
Commercial paper	7,497		—		7,497			—
Certificates of deposit	14,663		—		14,663			—
	$	161,905	$	—	$	161,905		$	—
Investments
U.S. government agency notes	$	19,378	$	—	$	19,378		$	—
Corporate debt securities	10,320		—		10,320			—
	$	29,698	$	—	$	29,698		$	—
The Company's marketable securities and investments have been valued on the basis of valuations provided by third-party pricing services, as derived from such services' pricing models. Inputs to the models may include, but are not limited to, reported trades, executable bid and asked prices, broker/dealer quotations, prices or yields of securities with similar characteristics, benchmark curves or information pertaining to the issuer, as well as industry and economic events. The pricing services may use a matrix approach, which considers information regarding securities with similar characteristics to determine the valuation for a security. The Company is ultimately responsible for the condensed consolidated financial statements and underlying estimates. Accordingly, the Company assesses the reasonableness of the valuations provided by the third-party pricing services by reviewing actual trade data, broker/dealer quotes and other similar data, which are obtained from quoted market prices or other sources.

INVENTORY

INVENTORY	9 Months Ended
	Sep. 27, 2013
Inventory Disclosure [Abstract]	'
INVENTORY	'
	INVENTORY
	Inventory consists of the following (in thousands):
		September 27,			December 31,
		2013			2012
	On-hand final assemblies and finished goods inventories	$	18,895		$	22,009
	Deferred cost of goods sold	5,420			5,704
		24,315			27,713
	Less current portion	(22,058		)	(25,614		)
	Noncurrent portion (included in Other assets)	$	2,257		$	2,099

INTANGIBLE_ASSETS_AND_GOODWILL

INTANGIBLE ASSETS AND GOODWILL	9 Months Ended
	Sep. 27, 2013
Goodwill and Intangible Assets Disclosure [Abstract]	'
INTANGIBLE ASSETS AND GOODWILL	'
	INTANGIBLE ASSETS AND GOODWILL
	The Company's intangible assets at September 27, 2013 and December 31, 2012 consist of the following (dollars in thousands):
	September 27, 2013	Weighted average amortization period		Cost				Accumulated				Net
		(years)						amortization				carrying value
	Intellectual property	5		$	999			$	999			$	—
	Developed technology	5.03		9,080				2,229				6,851
	Customer relationships	5.3		6,140				2,280				3,860
	Order backlog	0.33		860				860				—
	Internal use software	3		730				264				466
		4.35		$	17,809			$	6,632			$	11,177
	December 31, 2012	Weighted average amortization period		Cost				Accumulated				Net
		(years)						amortization				carrying value
	Intellectual property	5		$	2,999			$	2,199			$	800
	Developed technology	5.03		9,080				730				8,350
	Customer relationships	5.3		6,140				702				5,438
	Order backlog	0.33		860				860				—
	Internal use software	3		730				81				649
		4.35		$	19,809			$	4,572			$	15,237
	Amortization expense for intangible assets for the three and nine months ended September 27, 2013 and September 28, 2012 was as follows (in thousands):
		Three months ended								Nine months ended						Statement of operations classification
		September 27, 2013				September 28, 2012				September 27, 2013				September 28, 2012
	Intellectual property	$	—			$	100			$	200			$	300	Research and development
	Developed technology	500				183				1,499				183		Cost of revenue - product
	Customer relationships	526				175				1,578				175		Sales and marketing
	Order backlog	—				216				—				216		Cost of revenue - product
	Internal use software	61				30				183				30		Cost of revenue - product
		$	1,087			$	704			$	3,460			$	904
	In connection with the preparation of its financial statements for the second quarter of fiscal 2013, the Company reviewed its intangible assets and other long-lived assets for impairment indicators. The Company determined that a triggering event had occurred relative to one of its intellectual property intangible assets that had been acquired during fiscal 2010. During the three months ended June 28, 2013, the Company discontinued its development of this technology and determined that there were no alternative uses of the technology within either its existing or future product lines. Additionally, based on the age and resulting obsolescence of such technology, the Company concluded that the fair value was nominal based on a discounted cash flow model. As a result, the Company recorded an impairment charge of $0.6 million in the three months ended June 28, 2013 to write down the carrying value of the asset to zero. This expense is included as a component of research and development expense in the Company's condensed consolidated statements of operations for the nine months ended September 27, 2013. The nonrecurring fair value measurement of the impairment of the intellectual property was categorized in Level 3 of the fair value hierarchy.
	Estimated future amortization expense for the Company's intangible assets at September 27, 2013 is as follows (in thousands):
	Years ending December 31,
	Remainder of 2013	$	1,087
	2014	3,235
	2015	2,367
	2016	1,933
	2017	1,900
	Thereafter	655
		$	11,177
	Goodwill is recorded when the consideration for an acquisition exceeds the fair value of net tangible and identifiable intangible assets acquired. Other than the purchase price adjustments discussed in Note 2 and retrospectively recorded as of December 31, 2012, there were no changes to the carrying value of the Company's goodwill in the three or nine months ended September 27, 2013.
	The changes in the carrying value of the Company's goodwill in the nine months ended September 28, 2012 were as follows (in thousands):
	Balance at January 1, 2012:
	Goodwill	$	8,168
	Accumulated impairment losses	(3,106		)
		5,062
	Acquisition of NET	27,199
	Balance at September 28, 2012	$	32,261

ACCRUED_EXPENSES

ACCRUED EXPENSES	9 Months Ended
	Sep. 27, 2013
Payables and Accruals [Abstract]	'
ACCRUED EXPENSES	'
	ACCRUED EXPENSES
	Accrued expenses consist of the following (in thousands):
		September 27,		December 31,
		2013		2012
	Employee compensation and related costs	$	16,640	$	15,799
	Other	9,327		10,413
		$	25,967	$	26,212

RESTRUCTURING_ACCRUAL

RESTRUCTURING ACCRUAL	9 Months Ended
	Sep. 27, 2013
Restructuring and Related Activities [Abstract]	'
RESTRUCTURING ACCRUAL	'
	RESTRUCTURING ACCRUAL
	On August 7, 2012, the Company announced that it had committed to a restructuring initiative to streamline operations and reduce operating costs by closing and consolidating certain facilities and reducing its worldwide workforce. In connection with this initiative, the Company recorded $4.8 million of restructuring expense in the nine months ended September 27, 2013, comprised of $4.5 million for severance and related costs in connection with reducing the Company's workforce and $0.3 million related to facilities. Of this amount, the Company recorded $1.2 million in the three months ended September 27, 2013 for severance and related costs; $1.7 million in the three months ended June 28, 2013, comprised of $1.4 million for severance and related costs and $0.3 million for facility costs; and $1.9 million in the three months ended March 29, 2013, primarily for severance and related costs. The Company had recorded $7.7 million of restructuring expense in the year ended December 31, 2012, of which $5.2 million remained accrued at December 31, 2012.
	The table below summarizes the restructuring accrual activity for the nine months ended September 27, 2013 (in thousands):
		Balance at		Initiatives		Cash			Balance at
		January 1,		charged to		payments			September 27,
		2013		expense					2013
	Severance	$	1,135	$	4,478	$	(3,435	)	$	2,178
	Facilities	4,100		309		(1,102		)	3,307
		$	5,235	$	4,787	$	(4,537	)	$	5,485
	The Company expects to complete the restructuring payments related to severance in the fourth quarter of fiscal 2014 and the payments related to facilities in fiscal 2016. The portion of restructuring payments due more than one year from the balance sheet date is included in Other long-term liabilities in the Company's condensed consolidated balance sheets. The long-term portions of accrued restructuring were $2.1 million at September 27, 2013 and $2.7 million at December 31, 2012. The Company expects to record restructuring expense of approximately $2 million in the fourth quarter of fiscal 2013.

DEBT

DEBT	9 Months Ended
	Sep. 27, 2013
Debt Disclosure [Abstract]	'
DEBT	'
	DEBT
	The Company has determined that the estimated fair value of its $2.4 million of aggregate principal amount of outstanding debt due in 2014 equaled its carrying value at both September 27, 2013 and December 31, 2012. Although the debt can be publicly traded, there have been no trading transactions since 2010 and accordingly, the Company has categorized it in Level 2 within the fair value hierarchy.

STOCKHOLDER_RIGHTS_PLAN

STOCKHOLDER RIGHTS PLAN	9 Months Ended
	Sep. 27, 2013
Equity [Abstract]	'
STOCKHOLDER RIGHTS PLAN	'
	STOCKHOLDER RIGHTS PLAN
	On June 21, 2013, the Company entered into an amendment to its stockholder rights agreement, as amended (the "Rights Plan"), to extend the expiration date of the rights in such Rights Plan from June 26, 2013 to June 26, 2015. The amendment was not in response to any acquisition proposal and no other amendments were made to the Rights Plan. The Rights Plan was originally adopted on June 26, 2008 and subsequently extended to June 26, 2013 on June 10, 2011.
	Under the Rights Plan, preferred stock purchase rights (the "Rights") were distributed as a dividend at the rate of one Right per share of common stock held by stockholders of record as of the close of business on July 7, 2008. Each Right entitles the stockholder to purchase from the Company a unit consisting of one one-thousandth of a share (a "Unit") of preferred stock at a purchase price of $25.00, subject to adjustment.
	The Rights generally will be exercisable only if a person or group acquires beneficial ownership of 15% or more of the Company's common stock (which includes for this purpose shares of common stock referenced in derivative transactions or securities), or commences or publicly announces a tender or exchange offer upon consummation of which they would beneficially own 15% or more of the Company's common stock. Subject to certain conditions, a person or group who beneficially owned 15% or more of the outstanding shares of the Company's common stock prior to the adoption of the Rights Plan did not cause the Rights to become exercisable upon adoption of the Rights Plan. Should the Rights become exercisable, the effect would be to dilute the ownership of the beneficial owner(s) who triggered the Rights, as that beneficial owner or group of owners would not receive the Units.

COMMON_STOCK_REPURCHASES_Notes

COMMON STOCK REPURCHASES (Notes)	9 Months Ended
	Sep. 27, 2013
Equity [Abstract]	'
COMMON STOCK REPURCHASES	'
	COMMON STOCK REPURCHASES
	On July 29, 2013, the Company announced that its Board of Directors had authorized a stock buyback program to repurchase up to $100 million of the Company's common stock from time to time on the open market or in privately negotiated transactions. The timing and amount of any shares repurchased will be determined by the Company's management based on its evaluation of market conditions and other factors. The Company may elect to implement a 10b5-1 repurchase program, which would permit shares to be repurchased when the Company might otherwise be precluded from doing so under insider trading laws. The buyback program may be suspended or discontinued at any time. The buyback program is being funded using the Company's working capital.
	During both the three and nine months ended September 27, 2013, the Company spent $37.3 million, including transaction fees, to repurchase and retire 10.8 million shares of its common stock under the buyback program.

STOCKBASED_COMPENSATION_PLANS

STOCK-BASED COMPENSATION PLANS	9 Months Ended
	Sep. 27, 2013
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]	'
STOCK-BASED COMPENSATION PLANS	'
	STOCK-BASED COMPENSATION PLANS
	The Company's 2007 Stock Incentive Plan, as amended, (the "2007 Plan"), provides for the award of options to purchase the Company's common stock ("stock options"), stock appreciation rights ("SARs"), restricted common stock ("restricted stock"), performance-based awards, restricted stock units ("RSUs") and other stock-based awards to employees, officers, directors (including those directors who are not employees or officers of the Company), consultants and advisors of the Company and its subsidiaries. At its June 12, 2013 annual meeting of stockholders, the Company's stockholders approved an amendment to the 2007 Plan, which increased the number of shares available for future grant by 21 million shares.
	The Company's 2008 Stock Incentive Plan provides for the award of stock options, SARs, restricted stock, performance-based awards and RSUs to former employees of NET who subsequently became employees of Sonus and Sonus employees hired subsequent to the NET Acquisition Date.
	In March 2013, 21 executives of the Company, including Raymond P. Dolan, the Company's President and Chief Executive Officer ("Mr. Dolan"), elected to receive bonuses with respect to fiscal 2013 (collectively, the "2013 Bonus"), if any are earned, in the form of shares of the Company's common stock (collectively, the "2013 Bonus Shares"). The 2013 Bonus Shares, if any are granted, will be granted on a date concurrent with the timing of normal 2013 bonus payouts and will be fully vested as of the date of grant, with the number of 2013 Bonus Shares calculated by dividing amounts equal to 1.5 times the respective 2013 Bonus amounts earned, as determined by the Compensation Committee of the Company's Board of Directors (the "Compensation Committee") by the closing price of the Company's common stock on the date of grant. The Company is recording stock-based compensation expense for the 2013 Bonus Shares commensurate with the expected achievement level represented by the Company's accrual for its company-wide cash bonus program, as the performance metrics for each are consistent. Because no shares have been granted in connection with the 2013 Bonus, there are no shares related to the 2013 Bonus reported in the restricted stock grant table below.
	On February 15, 2013, Mr. Dolan elected to accept restricted shares of the Company's common stock in lieu of his base salary for the period from January 1, 2013 through December 31, 2013. Mr. Dolan had previously not received any salary payments from the Company for this period. On February 15, 2013, the Company granted Mr. Dolan 183,824 shares of restricted common stock (the "Salary Shares") having a total grant date fair value of $500,000, equal to Mr. Dolan's base salary for the year ending December 31, 2013. The number of shares was calculated by dividing Mr. Dolan's base salary for the year by $2.72, the closing price of the Company's common stock on the date of grant. The Salary Shares will vest on December 31, 2013. If Mr. Dolan's employment is terminated by Mr. Dolan with Good Reason (as defined in his employment agreement, as amended) or his employment is terminated by the Company without Cause (as defined in his employment agreement, as amended) before December 31, 2013, a pro rata portion of the Salary Shares will vest on the date of such termination. If Mr. Dolan terminates his employment without Good Reason or his employment is terminated by the Company for Cause before December 31, 2013, he will forfeit the Salary Shares. The Company is recording stock-based compensation expense related to the Salary Shares ratably for the period of January 1, 2013 through December 31, 2013. The Salary Shares are included in the amount reported as "Granted" in the restricted stock grant table below.
	On February 14, 2013, the Compensation Committee determined that eight executives of the Company, excluding Mr. Dolan, would receive their bonuses with respect to fiscal 2012 in the form of restricted shares of the Company's common stock equal to 100% of their respective target bonus amounts for fiscal 2012 (collectively, the "Executive Bonus Shares"). The number of shares granted to each executive was calculated by dividing his/her target bonus amount by the closing price of the Company's common stock on February 15, 2013, the date of grant. The Executive Bonus Shares vested 50% on August 15, 2013 and the remaining 50% will vest on February 15, 2014, contingent upon each such executive's continued employment with the Company on the last vesting date. The Company had accrued for the cash payment of bonuses at the expected company-wide cash payout percentage amount at December 31, 2012, which amounts were less than the target bonus amounts for each individual. The Company is recording the unamortized expense related to the Executive Bonus Shares as stock-based compensation expense through February 15, 2014. These shares are reported as "Granted" in the restricted stock grant table below.
	On August 7, 2012, Mr. Dolan elected to receive his fiscal year 2012 bonus, if earned, in the form of restricted shares of the Company's common stock (the “Dolan Bonus Shares”). On August 10, 2012, the Company granted Mr. Dolan 421,348 Dolan Bonus Shares, which equaled Mr. Dolan's potential 2012 bonus at the maximum level of achievement (150% of Mr. Dolan's annual base salary), divided by $1.78, the closing price of the Company's common stock on the date of grant. During fiscal 2012, the Company recorded stock-based compensation expense for the Dolan Bonus Shares commensurate with the expected achievement level represented by the Company's accrual for its company-wide cash bonus program, as the performance metrics for each were consistent. The Dolan Bonus Shares represented the performance-based stock award shares reported as “Unvested balance at January 1, 2013” in the performance-based stock awards table below. On February 14, 2013, the Compensation Committee determined that Mr. Dolan had earned 280,899 Dolan Bonus Shares, of which 50% vested on August 15, 2013 and the remaining 50% will vest on February 15, 2014, subject to Mr. Dolan's continued employment with the Company on the last vesting date. The Company is recording the unamortized expense related to the Dolan Bonus Shares, including incremental expense arising from the modification of this award, through February 15, 2014. Mr. Dolan forfeited the remaining 140,449 Dolan Bonus Shares on February 14, 2013, and these shares are reported as "Forfeited" in the performance-based stock awards table below.
	Certain members of the Company's Board of Directors elected to receive their annual cash retainer in shares of the Company's common stock in lieu of cash payments. Accordingly, the Company granted approximately 73,000 shares in the aggregate under the 2007 Plan to such members of the Board of Directors, of which approximately 40,000 shares were granted on February 15, 2013 and approximately 33,000 shares were granted on June 17, 2013. All such shares vested immediately. The shares are reported as both "Granted" and "Vested" in the restricted stock grants table below.
	Stock Options
	The activity related to the Company's outstanding stock options during the nine months ended September 27, 2013 is as follows:
		Number of			Weighted			Weighted		Aggregate
		Shares			Average			Average		Intrinsic Value
					Exercise Price			Remaining		(in thousands)
								Contractual Term
								(years)
	Outstanding at January 1, 2013	25,116,398			$	3.46
	Granted	13,043,856			$	2.92
	Exercised	(1,166,397	)		$	2.01
	Forfeited	(1,398,660	)		$	2.62
	Expired	(2,312,336	)		$	4.78
	Outstanding at September 27, 2013	33,282,861			$	3.25		7.21		$	16,860
	Vested or expected to vest at September 27, 2013	30,487,280			$	3.29		7.02		$	15,294
	Exercisable at September 27, 2013	14,228,903			$	3.85		4.76		$	5,694
	The grant date fair values of options to purchase common stock granted in the three and nine months ended September 27, 2013 were estimated using the Black-Scholes valuation model with the following assumptions:
		Three months ended		Nine months ended
		September 27,		September 27,
		2013		2013
	Risk-free interest rate	1.51% - 1.71%		0.82% - 1.71%
	Expected dividends	—		—
	Weighted average volatility	57.60%		63.20%
	Expected life (years)	4.5		4.5 - 6.0
	Additional information regarding the Company's stock options for the three and nine months ended September 27, 2013 is as follows:
		Three months ended				Nine months ended
		September 27,				September 27,
		2013				2013
	Weighted average grant date fair value of stock options granted	$	1.58			$	1.49
	Total intrinsic value of stock options exercised (in thousands)	$	398			$	1,185
	Cash received from the exercise of stock options (in thousands)	$	1,056			$	2,393
	Restricted Stock Grants - Restricted Stock Awards and Restricted Stock Units
	The Company's outstanding restricted stock grants consist of both restricted stock awards and RSUs. The activity related to the Company's unvested restricted stock grants for the nine months ended September 27, 2013 is as follows:
		Shares			Weighted
					Average
					Grant Date
					Fair Value
	Unvested balance at January 1, 2013	617,203			$	2.45
	Granted	1,334,086			$	2.82
	Vested	(634,514	)		$	2.56
	Forfeited	(54,039	)		$	2.66
	Unvested balance at September 27, 2013	1,262,736			$	2.77
	The total fair value of restricted stock grant shares that vested during the nine months ended September 27, 2013 was $1.6 million.
	Performance-Based Stock Awards
	The activity related to the Company's performance-based stock awards for the nine months ended September 27, 2013 is as follows:
		Shares			Weighted
					Average
					Grant Date
					Fair Value
	Unvested balance at January 1, 2013	421,348			$	1.78
	Granted	1,984,500			$	2.72
	Vested	(954,292	)		$	2.58
	Forfeited	(140,449	)		$	1.78
	Unvested balance at September 27, 2013	1,311,107			$	2.62
	On February 14, 2013, the Compensation Committee took certain actions regarding performance-based stock awards that had been awarded in previous years but for which the grant date criteria had not been met as of December 31, 2012. These actions included determining that a certain number of these performance-based shares would vest as of February 15, 2013 (the “Vested Performance Shares”) and subjecting the remaining performance-based shares (the “Future Performance Shares”) to further performance and service conditions. Accordingly, as of February 15, 2013 the grant date criteria were met for both the Vested Performance Shares and the Future Performance Shares and they are reported as "Granted" in the table above. The performance conditions relate to either a portion of or the full fiscal 2013 year and the service conditions were implemented through vesting schedules individually assigned to each Future Performance Share award that provide for service-based vesting through fiscal 2015. On July 26, 2013, the Compensation Committee determined that the performance conditions related to the Future Performance Shares had been satisfied based on the Company's performance for the six months ended June 28, 2013 and accordingly, all of the Future Performance Shares will vest contingent upon continued employment with the Company on the vesting dates. The Company had previously estimated that the conditions related to the Future Performance Shares would be satisfied by June 28, 2013 and had recorded expense in the first and second quarters of 2013 based on that estimate. The Company is recording the unamortized expense related to the Future Performance Shares based on the vesting dates of the respective awards.
	Stock-Based Compensation
The condensed consolidated statements of operations include stock-based compensation for the three and nine months ended September 27, 2013 and September 28, 2012 as follows (in thousands):
	Three months ended							Nine months ended
	September 27, 2013				September 28, 2012			September 27, 2013			28-Sep-12
Product cost of revenue	$	46			$	41		$	128		$	130
Service cost of revenue	299				211			761			595
Research and development	903				524			2,402			1,773
Sales and marketing	1,313				500			3,631			1,458
General and administrative	1,812				1,124			6,215			2,584
	$	4,373			$	2,400		$	13,137		$	6,540
There is no income tax benefit for employee stock-based compensation expense for the three and nine months ended September 27, 2013 or September 28, 2012 due to the valuation allowance recorded.
At September 27, 2013, there was $26.7 million, net of expected forfeitures, of unrecognized stock-based compensation expense related to unvested stock options and restricted stock awards. This expense is expected to be recognized over a weighted average period of approximately three years.

MAJOR_CUSTOMERS

MAJOR CUSTOMERS	9 Months Ended
	Sep. 27, 2013
Risks and Uncertainties [Abstract]	'
MAJOR CUSTOMERS	'
	MAJOR CUSTOMERS
	The following customers each contributed 10% or more of the Company's revenue in at least one of the three or nine month periods ended September 27, 2013 and September 28, 2012:
		Three months ended		Nine months ended
		September 27,	September 28,	September 27,	September 28,
		2013	2012	2013	2012
	AT&T Inc.	18%	*	17%	24%
	Level 3 Communications	*	12%	*	*
	__________________________________
	* Represents less than 10% of revenue
	At September 27, 2013, one customer accounted for 10% or more of the Company's accounts receivable balance, representing approximately 21% of the Company's accounts receivable balance. At December 31, 2012, one customer accounted for 10% or more of the Company's accounts receivable balance, representing approximately 25% of the Company's accounts receivable balance. The Company performs ongoing credit evaluations of its customers and generally does not require collateral on accounts receivable. The Company maintains an allowance for doubtful accounts and such losses have been within management's expectations.

GEOGRAPHIC_INFORMATION

GEOGRAPHIC INFORMATION	9 Months Ended
	Sep. 27, 2013
Segment Reporting [Abstract]	'
GEOGRAPHIC INFORMATION	'
	GEOGRAPHIC INFORMATION
	The Company's classification of revenue by geographic area is determined by the location to which the product is shipped or where the services are performed. The following table summarizes revenue by geographic area as a percentage of total revenue:
		Three months ended				Nine months ended
		September 27,		September 28,		September 27,		September 28,
		2013		2012		2013		2012
	United States	66	%	76	%	70	%	75	%
	Europe, Middle East and Africa	15		13		12		10
	Japan	8		*		11		9
	Other Asia Pacific	7		10		5		5
	Other	4		1		2		1
		100	%	100	%	100	%	100	%
	* Represents less than 1% of revenue
	International revenue, both as a percentage of total revenue and absolute dollars, may vary from one period to the next, and accordingly, historical data may not be indicative of future periods.

INCOME_TAXES

INCOME TAXES	9 Months Ended
	Sep. 27, 2013
Income Tax Disclosure [Abstract]	'
INCOME TAXES	'
	INCOME TAXES
	The Company's income tax provisions for the nine months ended September 27, 2013 and September 28, 2012 reflect the Company's estimates of the effective rates expected to be applicable for the respective full years, adjusted for any discrete events, which are recorded in the period that they occur. These estimates are reevaluated each quarter based on the Company's estimated tax expense for the full year. The estimated effective rates for the nine months ended September 27, 2013 and September 28, 2012 do not include any benefit for the Company's domestic losses, as the Company has concluded that a valuation allowance on any domestic benefit is required.
	In September 2013, the U.S. Department of the Treasury and the Internal Revenue Service released final regulations relating to guidance on applying tax rules to amounts paid to acquire, produce or improve tangible personal property as well as rules for materials and supplies. The Company is currently assessing these rules and the impact they will have on its consolidated financial statements, if any.

COMMITMENTS_AND_CONTINGENCIES

COMMITMENTS AND CONTINGENCIES	9 Months Ended
	Sep. 27, 2013
Commitments and Contingencies Disclosure [Abstract]	'
COMMITMENTS AND CONTINGENCIES	'
	COMMITMENTS AND CONTINGENCIES
	The Company is often a party to disputes and legal proceedings that it considers routine and incidental to its business. In the normal course of business, the Company enters into contractual commitments to purchase services, materials, components, and finished goods from suppliers. Under agreements with certain contract manufacturers, the Company may be liable for purchased raw materials procured for the Company by the applicable contract manufacturer. Management does not expect the results of any of these actions to have a material effect on the Company's business or consolidated financial statements.

SUBSEQUENT_EVENTS

SUBSEQUENT EVENTS	9 Months Ended
	Sep. 27, 2013
Subsequent Events [Abstract]	'
SUBSEQUENT EVENTS	'
	SUBSEQUENT EVENTS
	On October 24, 2013, Mark T. Greenquist accepted an offer of employment as Chief Financial Officer of the Company, effective November 1, 2013.
	On October 29, 2013, Maurice L. Castonguay resigned as Senior Vice President and Chief Financial Officer, effective November 1, 2013.

BASIS_OF_PRESENTATION_Policies

BASIS OF PRESENTATION (Policies)	9 Months Ended
	Sep. 27, 2013
Accounting Policies [Abstract]	'
Basis of Presentation	'
	Basis of Presentation
	In the opinion of management, the accompanying unaudited condensed consolidated financial statements include all adjustments, consisting only of normal recurring items, necessary for their fair presentation with accounting principles generally accepted in the United States of America ("GAAP") and with the rules and regulations of the U.S. Securities and Exchange Commission ("SEC").
	Interim results are not necessarily indicative of results for a full year or any future interim period. The information included in this Quarterly Report on Form 10-Q should be read in conjunction with the Company's Annual Report on Form 10-K for the year ended December 31, 2012 ("Annual Report") filed with the SEC on March 6, 2013.
	On August 24, 2012, the Company completed the acquisition of Network Equipment Technologies, Inc. (“NET”). The financial results of NET are included in the Company's condensed consolidated financial statements for the three and nine months ended September 27, 2013 and for the three and nine months ended September 28, 2012 for the period subsequent to August 24, 2012.
	The Company reported acquisition-related expenses of approximately $967,000 as a component of general and administrative expenses in its Quarterly Report on Form 10-Q for the quarter ended June 29, 2012. The Company is now separately reporting this amount as acquisition-related expenses in the condensed statements of operations included herein.
Principles of Consolidation	'
	Principles of Consolidation
	The condensed consolidated financial statements include the accounts of Sonus and its wholly-owned subsidiaries. Intercompany transactions and balances have been eliminated in consolidation.
Use of Estimates and Judgments	'
	Use of Estimates and Judgments
	The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the reporting periods. Significant estimates and judgments relied upon in preparing these consolidated financial statements include accounting for business combinations, revenue recognition for multiple element arrangements, inventory valuations, assumptions used to determine the fair value of stock-based compensation, intangible assets and goodwill valuations, including impairments, legal contingencies and recoverability of Sonus' net deferred tax assets and the related valuation allowances. Sonus regularly assesses these estimates and records changes in estimates in the period in which they become known. Sonus bases its estimates on historical experience and various other assumptions that it believes to be reasonable under the circumstances. Actual results could differ from those estimates.
Financial Instruments	'
	Fair Value of Financial Instruments
	The carrying amounts of the Company's financial instruments, which include cash equivalents, marketable securities, investments, accounts receivable, accounts payable, convertible subordinated debt and other long-term liabilities, approximate their fair values.
Operating Segments	'
	Operating Segments
	The Company operates in a single segment. Operating segments are identified as components of an enterprise about which separate discrete financial information is available for evaluation by the chief operating decision maker in making decisions regarding resource allocation and assessing performance. To date, the chief operating decision maker has made such decisions and assessed performance at the company level, as one segment. The Company's chief operating decision maker is its President and Chief Executive Officer.
Recent Accounting Pronouncements	'
	Recent Accounting Pronouncements
	On July 18, 2013, the Financial Accounting Standards Board ("FASB") issued Accounting Standards Update ("ASU") 2013-11, Presentation of a Liability for an Unrecognized Tax Benefit When a Net Operating Loss Carryforward or Tax Credit Carryforward Exists ("ASU 2013-11"), which provides guidance on financial statement presentation of an unrecognized tax benefit when a net operating loss ("NOL") carryforward, a similar tax loss or a tax credit carryforward exists. The FASB's objective in issuing ASU 2013-11 is to eliminate diversity in practice resulting from a lack of guidance on this topic in current GAAP. ASU 2013-11 requires that an entity present an unrecognized tax benefit, or a portion of an unrecognized tax benefit, in the financial statements as a reduction to a deferred tax asset for an NOL carryforward, a similar tax loss or a tax credit unless certain conditions exist. ASU 2013-11 is effective for the Company beginning January 1, 2014. The Company does not expect the adoption of ASU 2013-11 to have an impact on its consolidated financial statements, as the Company currently applies the methodology prescribed by ASU 2013-11.
	On March 4, 2013, the FASB issued ASU 2013-05, Foreign Currency Matters (Topic 830) - Parent's Accounting for the Cumulative Translation Adjustment upon Derecognition of Certain Subsidiaries or Groups of Assets within a Foreign Entity or of an Investment in a Foreign Entity ("ASU 2013-05"), which indicates that the entire amount of a cumulative translation adjustment ("CTA") related to an entity's investment in a foreign entity should be released when there has been either: (a) a sale of a subsidiary or group of net assets within a foreign entity and the sale represents the substantially complete liquidation of the investment in a foreign entity; (b) the loss of a controlling financial interest in an investment in a foreign entity (i.e., the foreign entity is deconsolidated); or (c) the step acquisition of a foreign entity (i.e., when the accounting for an entity has changed from applying the equity method for an investment in a foreign entity to consolidating the foreign entity). ASU 2013-05 does not change the requirement to release a pro rata portion of the CTA of the foreign entity into earnings for a partial sale of an equity method investment in a foreign entity. ASU 2013-05 is effective for the Company beginning January 1, 2014, although early adoption is permitted. The Company does not expect the adoption of ASU 2013-05 to have a material impact on its consolidated financial statements.
	On February 5, 2013, the FASB issued ASU 2013-02, Comprehensive Income (Topic 220): Reporting of Amounts Reclassified Out of Accumulated Other Comprehensive Income ("ASU 2013-02"), which requires entities to disclose changes in accumulated other comprehensive income balances by component (i.e., unrealized gains or losses on available-for-sale securities or foreign-currency items) and significant items reclassified out of accumulated other comprehensive income by component either on the face of the income statement or as a separate footnote to the financial statements. ASU 2013-02 does not change the current requirements for interim financial statement reporting of comprehensive income. ASU 2013-02 became effective for the Company on January 1, 2013. The Company does not have significant items reclassified out of accumulated other comprehensive income and accordingly, the adoption of ASU 2013-02 did not impact the Company's condensed consolidated financial statements.

ACQUISITION_OF_NET_Tables

ACQUISITION OF NET (Tables)	9 Months Ended
	Sep. 27, 2013
Business Combinations [Abstract]	'
Summary of preliminary allocation of the purchase consideration	'
	A summary of the allocation of the purchase consideration for NET is as follows (in thousands):
	Fair value of consideration transferred:
	Cash, net of cash acquired	$	35,508
	Fair value of equity awards assumed	892
	Fair value of total consideration	$	36,400
	Fair value of assets acquired and liabilities assumed:
	Marketable securities	$	5,359
	Deferred income taxes	681
	Other current assets	13,388
	Property and equipment	4,694
	Noncurrent investments	10,167
	Intangible assets	16,810
	Goodwill	27,317
	Other noncurrent assets	1,843
	Current liabilities	(9,350		)
	Debt	(34,208		)
	Other long-term liabilities	(301		)
		$	36,400
Schedule of Pro Forma Results from Business Acquisition	'
	The unaudited pro forma results do not reflect any operating efficiencies or potential cost savings which may result from the consolidation of the operations of the Company and NET. Accordingly, these unaudited pro forma results are presented for illustrative purposes and are not intended to represent or be indicative of the actual results of operations of the combined companies that would have been achieved had the acquisition occurred as of January 1, 2011, nor are they intended to represent or be indicative of future results of operations (in thousands, except per share amount):
		Three months ended			Nine months ended
		September 28, 2012			September 28, 2012
	Revenue	$	63,369		$	207,878
	Net loss	$	(13,496	)	$	(48,765	)
	Loss per share	$	(0.05	)	$	(0.17	)
Schedule of Components of Acquisition Related Costs	'
	The components of acquisition-related costs included in the Company's results of operations for the three and nine months ended September 28, 2012 are as follows (in thousands):
		Three months ended			Nine months ended
		September 28, 2012			September 28, 2012
	Professional and services fees	$	2,048		$	3,015
	Change of control agreements	2,042			2,042
		$	4,090		$	5,057

EARNINGS_LOSS_PER_SHARE_Tables

EARNINGS (LOSS) PER SHARE (Tables)	9 Months Ended
	Sep. 27, 2013
Earnings Per Share [Abstract]	'
Schedule of calculations of shares used to compute basic and diluted earnings (loss) per share	'
	The calculations of shares used to compute basic and diluted loss per share are as follows (in thousands):
		Three months ended		Nine months ended
		September 27,	September 28,	September 27,	September 28,
		2013	2012	2013	2012
	Weighted average shares outstanding—basic	279,209	280,145	281,041	279,854
	Potential dilutive common shares	—	—	—	—
	Weighted average shares outstanding—diluted	279,209	280,145	281,041	279,854

CASH_EQUIVALENTS_MARKETABLE_SE1

CASH EQUIVALENTS, MARKETABLE SECURITIES AND INVESTMENTS (Tables)	9 Months Ended
	Sep. 27, 2013
Investments, All Other Investments [Abstract]	'
Schedule of amortized cost, gross unrealized gains and losses and fair value of marketable debt and equity securities and investments	'
	The amortized cost, gross unrealized gains and losses and fair value of the Company's marketable debt and equity securities and investments at September 27, 2013 and December 31, 2012 were comprised of the following (in thousands):
		27-Sep-13
		Amortized		Unrealized		Unrealized			Fair
		cost		gains		losses			value
	Cash equivalents	$	33,110	$	—	$	—		$	33,110
	Marketable securities
	U.S. government agency notes	$	47,606	$	30	$	—		$	47,636
	Corporate debt securities	65,241		24		(20		)	65,245
	Commercial paper	11,240		4		—			11,244
	Certificates of deposit	4,050		3		(1		)	4,052
		$	128,137	$	61	$	(21	)	$	128,177
	Investments
	U.S. government agency notes	$	20,471	$	8	$	(3	)	$	20,476
	Foreign government notes	1,250		—		(1		)	1,249
	Corporate debt securities	45,188		16		(40		)	45,164
		$	66,909	$	24	$	(44	)	$	66,889
		31-Dec-12
		Amortized		Unrealized		Unrealized			Fair
		cost		gains		losses			value
	Cash equivalents	$	69,389	$	—	$	—		$	69,389
	Marketable securities
	U.S. government agency notes	$	53,646	$	22	$	—		$	53,668
	Foreign government notes	2,000		1		—			2,001
	Corporate debt securities	84,047		34		(5		)	84,076
	Commercial paper	7,492		5		—			7,497
	Certificates of deposit	14,650		13		—			14,663
		$	161,835	$	75	$	(5	)	$	161,905
	Investments
	U.S. government agency notes	$	19,358	$	20	$	—		$	19,378
	Corporate debt securities	10,306		20		(6		)	10,320
		$	29,664	$	40	$	(6	)	$	29,698
Schedule of fair value of financial assets	'
	The following table shows the fair value of the Company's financial assets at September 27, 2013 and December 31, 2012. These financial assets are comprised of the Company's available-for-sale debt and equity securities and reported under the captions Cash and cash equivalents, Marketable securities and Investments in the consolidated balance sheets (in thousands):
				Fair value measurements at
				September 27, 2013 using:
		Total carrying		Quoted prices		Significant other			Significant
		value at		in active		observable			unobservable
		September 27,		markets		inputs			inputs
		2013		(Level 1)		(Level 2)			(Level 3)
	Cash equivalents	$	33,110	$	33,110	$	—		$	—
	Marketable securities
	U.S. government agency notes	$	47,636	$	—	$	47,636		$	—
	Corporate debt securities	65,245		—		65,245			—
	Commercial paper	11,244		—		11,244			—
	Certificates of deposit	4,052		—		4,052			—
		$	128,177	$	—	$	128,177		$	—
	Investments
	U.S. government agency notes	$	20,476	$	—	$	20,476		$	—
	Foreign government notes	1,249		—		1,249			—
	Corporate debt securities	45,164		—		45,164			—
		$	66,889	$	—	$	66,889		$	—
				Fair value measurements at
				December 31, 2012 using:
		Total carrying		Quoted prices		Significant other			Significant
		value at		in active		observable			unobservable
		December 31,		markets		inputs			inputs
		2012		(Level 1)		(Level 2)			(Level 3)
	Cash equivalents	$	69,389	$	68,389	$	1,000		$	—
	Marketable securities
	U.S. government agency notes	$	53,668	$	—	$	53,668		$	—
	Foreign government notes	2,001		—		2,001			—
	Corporate debt securities	84,076		—		84,076			—
	Commercial paper	7,497		—		7,497			—
	Certificates of deposit	14,663		—		14,663			—
		$	161,905	$	—	$	161,905		$	—
	Investments
	U.S. government agency notes	$	19,378	$	—	$	19,378		$	—
	Corporate debt securities	10,320		—		10,320			—
		$	29,698	$	—	$	29,698		$	—

INVENTORY_Tables

INVENTORY (Tables)	9 Months Ended
	Sep. 27, 2013
Inventory Disclosure [Abstract]	'
Schedule of inventory	'
	Inventory consists of the following (in thousands):
		September 27,			December 31,
		2013			2012
	On-hand final assemblies and finished goods inventories	$	18,895		$	22,009
	Deferred cost of goods sold	5,420			5,704
		24,315			27,713
	Less current portion	(22,058		)	(25,614		)
	Noncurrent portion (included in Other assets)	$	2,257		$	2,099

INTANGIBLE_ASSETS_AND_GOODWILL1

INTANGIBLE ASSETS AND GOODWILL (Tables)	9 Months Ended
	Sep. 27, 2013
Goodwill and Intangible Assets Disclosure [Abstract]	'
Schedule of intangible assets	'
	The Company's intangible assets at September 27, 2013 and December 31, 2012 consist of the following (dollars in thousands):
	September 27, 2013	Weighted average amortization period		Cost				Accumulated				Net
		(years)						amortization				carrying value
	Intellectual property	5		$	999			$	999			$	—
	Developed technology	5.03		9,080				2,229				6,851
	Customer relationships	5.3		6,140				2,280				3,860
	Order backlog	0.33		860				860				—
	Internal use software	3		730				264				466
		4.35		$	17,809			$	6,632			$	11,177
	December 31, 2012	Weighted average amortization period		Cost				Accumulated				Net
		(years)						amortization				carrying value
	Intellectual property	5		$	2,999			$	2,199			$	800
	Developed technology	5.03		9,080				730				8,350
	Customer relationships	5.3		6,140				702				5,438
	Order backlog	0.33		860				860				—
	Internal use software	3		730				81				649
		4.35		$	19,809			$	4,572			$	15,237
Schedule of amortization expense related to intangible assets	'
	Amortization expense for intangible assets for the three and nine months ended September 27, 2013 and September 28, 2012 was as follows (in thousands):
		Three months ended								Nine months ended						Statement of operations classification
		September 27, 2013				September 28, 2012				September 27, 2013				September 28, 2012
	Intellectual property	$	—			$	100			$	200			$	300	Research and development
	Developed technology	500				183				1,499				183		Cost of revenue - product
	Customer relationships	526				175				1,578				175		Sales and marketing
	Order backlog	—				216				—				216		Cost of revenue - product
	Internal use software	61				30				183				30		Cost of revenue - product
		$	1,087			$	704			$	3,460			$	904
Schedule of estimated future amortization expense for intangible assets	'
	Estimated future amortization expense for the Company's intangible assets at September 27, 2013 is as follows (in thousands):
	Years ending December 31,
	Remainder of 2013	$	1,087
	2014	3,235
	2015	2,367
	2016	1,933
	2017	1,900
	Thereafter	655
		$	11,177
Schedule of goodwill	'
	The changes in the carrying value of the Company's goodwill in the nine months ended September 28, 2012 were as follows (in thousands):
	Balance at January 1, 2012:
	Goodwill	$	8,168
	Accumulated impairment losses	(3,106		)
		5,062
	Acquisition of NET	27,199
	Balance at September 28, 2012	$	32,261

ACCRUED_EXPENSES_Tables

ACCRUED EXPENSES (Tables)	9 Months Ended
	Sep. 27, 2013
Payables and Accruals [Abstract]	'
Schedule of accrued expenses	'
	Accrued expenses consist of the following (in thousands):
		September 27,		December 31,
		2013		2012
	Employee compensation and related costs	$	16,640	$	15,799
	Other	9,327		10,413
		$	25,967	$	26,212

RESTRUCTURING_ACCRUAL_Tables

RESTRUCTURING ACCRUAL (Tables)	9 Months Ended
	Sep. 27, 2013
Restructuring and Related Activities [Abstract]	'
Summary of restructuring accrual activity	'
	The table below summarizes the restructuring accrual activity for the nine months ended September 27, 2013 (in thousands):
		Balance at		Initiatives		Cash			Balance at
		January 1,		charged to		payments			September 27,
		2013		expense					2013
	Severance	$	1,135	$	4,478	$	(3,435	)	$	2,178
	Facilities	4,100		309		(1,102		)	3,307
		$	5,235	$	4,787	$	(4,537	)	$	5,485

STOCKBASED_COMPENSATION_PLANS_

STOCK-BASED COMPENSATION PLANS (Tables)	9 Months Ended
	Sep. 27, 2013
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]	'
Schedule of activity related to outstanding stock options	'
	The activity related to the Company's outstanding stock options during the nine months ended September 27, 2013 is as follows:
		Number of			Weighted			Weighted		Aggregate
		Shares			Average			Average		Intrinsic Value
					Exercise Price			Remaining		(in thousands)
								Contractual Term
								(years)
	Outstanding at January 1, 2013	25,116,398			$	3.46
	Granted	13,043,856			$	2.92
	Exercised	(1,166,397	)		$	2.01
	Forfeited	(1,398,660	)		$	2.62
	Expired	(2,312,336	)		$	4.78
	Outstanding at September 27, 2013	33,282,861			$	3.25		7.21		$	16,860
	Vested or expected to vest at September 27, 2013	30,487,280			$	3.29		7.02		$	15,294
	Exercisable at September 27, 2013	14,228,903			$	3.85		4.76		$	5,694
Schedule of assumptions used to estimate the fair value of options at the date of grant using the Black-Scholes option pricing model	'
	The grant date fair values of options to purchase common stock granted in the three and nine months ended September 27, 2013 were estimated using the Black-Scholes valuation model with the following assumptions:
		Three months ended		Nine months ended
		September 27,		September 27,
		2013		2013
	Risk-free interest rate	1.51% - 1.71%		0.82% - 1.71%
	Expected dividends	—		—
	Weighted average volatility	57.60%		63.20%
	Expected life (years)	4.5		4.5 - 6.0
Schedule of stock options, additional information	'
	Additional information regarding the Company's stock options for the three and nine months ended September 27, 2013 is as follows:
		Three months ended				Nine months ended
		September 27,				September 27,
		2013				2013
	Weighted average grant date fair value of stock options granted	$	1.58			$	1.49
	Total intrinsic value of stock options exercised (in thousands)	$	398			$	1,185
	Cash received from the exercise of stock options (in thousands)	$	1,056			$	2,393
Schedule of activity related to unvested restricted stock grants	'
	The activity related to the Company's unvested restricted stock grants for the nine months ended September 27, 2013 is as follows:
		Shares			Weighted
					Average
					Grant Date
					Fair Value
	Unvested balance at January 1, 2013	617,203			$	2.45
	Granted	1,334,086			$	2.82
	Vested	(634,514	)		$	2.56
	Forfeited	(54,039	)		$	2.66
	Unvested balance at September 27, 2013	1,262,736			$	2.77
Schedule of activity related to performance stock awards	'
	The activity related to the Company's performance-based stock awards for the nine months ended September 27, 2013 is as follows:
		Shares			Weighted
					Average
					Grant Date
					Fair Value
	Unvested balance at January 1, 2013	421,348			$	1.78
	Granted	1,984,500			$	2.72
	Vested	(954,292	)		$	2.58
	Forfeited	(140,449	)		$	1.78
	Unvested balance at September 27, 2013	1,311,107			$	2.62
Schedule of stock-based compensation expenses which are included in condensed consolidated statement of operations	'
	The condensed consolidated statements of operations include stock-based compensation for the three and nine months ended September 27, 2013 and September 28, 2012 as follows (in thousands):
		Three months ended							Nine months ended
		September 27, 2013				September 28, 2012			September 27, 2013			28-Sep-12
	Product cost of revenue	$	46			$	41		$	128		$	130
	Service cost of revenue	299				211			761			595
	Research and development	903				524			2,402			1,773
	Sales and marketing	1,313				500			3,631			1,458
	General and administrative	1,812				1,124			6,215			2,584
		$	4,373			$	2,400		$	13,137		$	6,540

MAJOR_CUSTOMERS_Tables

MAJOR CUSTOMERS (Tables)	9 Months Ended
	Sep. 27, 2013
Risks and Uncertainties [Abstract]	'
Schedule of customers contributing 10% or more of the revenue	'
	The following customers each contributed 10% or more of the Company's revenue in at least one of the three or nine month periods ended September 27, 2013 and September 28, 2012:
		Three months ended		Nine months ended
		September 27,	September 28,	September 27,	September 28,
		2013	2012	2013	2012
	AT&T Inc.	18%	*	17%	24%
	Level 3 Communications	*	12%	*	*
	__________________________________
	* Represents less than 10% of revenue

GEOGRAPHIC_INFORMATION_Tables

GEOGRAPHIC INFORMATION (Tables)	9 Months Ended
	Sep. 27, 2013
Segment Reporting [Abstract]	'
Summary of revenue by geographic area as a percentage of total revenue	'
	The Company's classification of revenue by geographic area is determined by the location to which the product is shipped or where the services are performed. The following table summarizes revenue by geographic area as a percentage of total revenue:
		Three months ended				Nine months ended
		September 27,		September 28,		September 27,		September 28,
		2013		2012		2013		2012
	United States	66	%	76	%	70	%	75	%
	Europe, Middle East and Africa	15		13		12		10
	Japan	8		*		11		9
	Other Asia Pacific	7		10		5		5
	Other	4		1		2		1
		100	%	100	%	100	%	100	%

BASIS_OF_PRESENTATION_Narrativ

BASIS OF PRESENTATION - Narrative (Details) (USD $)	3 Months Ended			9 Months Ended
In Thousands, unless otherwise specified	Sep. 27, 2013	Sep. 28, 2012	Jun. 29, 2012	Sep. 27, 2013	Sep. 28, 2012
				segment
Accounting Policies [Abstract]	'	'	'	'	'
Acquisition-related	$0	$4,090	$967	$0	$5,057
Number of reportable operating segments	'	'	'	1	'

ACQUISITION_OF_NET_Details

ACQUISITION OF NET - (Details) (USD $)	3 Months Ended			9 Months Ended		0 Months Ended	3 Months Ended		9 Months Ended
	Sep. 27, 2013	Sep. 28, 2012	Jun. 29, 2012	Sep. 27, 2013	Sep. 28, 2012	Aug. 24, 2012	Sep. 27, 2013	Sep. 28, 2012	Sep. 27, 2013	Sep. 28, 2012
						NET [Member]	NET [Member]	NET [Member]	NET [Member]	NET [Member]
Acquisition Of Net	'	'	'	'	'	'	'	'	'	'
Cash consideration	'	'	'	'	'	$41,500,000	'	'	'	'
Cash consideration per share of the acquired entity (in dollars per share)	'	'	'	'	'	$1.35	'	'	'	'
Increase to goodwill	'	'	'	'	'	'	-1,400,000	'	'	'
Decrease to other current assets	'	'	'	'	'	'	900,000	'	'	'
Increase to current liabilities	'	'	'	'	'	'	500,000	'	'	'
Period over which goodwill will be deductible for tax purpose	'	'	'	'	'	'	'	'	'15 years	'
Fair value of consideration transferred:	'	'	'	'	'	'	'	'	'	'
Cash, net of cash acquired	'	'	'	0	35,508,000	35,508,000	'	'	'	'
Assumption of equity awards in connection with acquisition of Network Technologies, Inc.	'	'	'	0	892,000	892,000	'	'	'	'
Fair value of total consideration	'	'	'	'	'	36,400,000	'	'	'	'
Allocation of the purchase consideration:	'	'	'	'	'	'	'	'	'	'
Marketable securities	'	'	'	'	'	5,359,000	'	'	'	'
Deferred income taxes	'	'	'	'	'	681,000	'	'	'	'
Other current assets	'	'	'	'	'	13,388,000	'	'	'	'
Property and equipment	'	'	'	'	'	4,694,000	'	'	'	'
Noncurrent investments	'	'	'	'	'	10,167,000	'	'	'	'
Intangible assets	'	'	'	'	'	16,810,000	'	'	'	'
Goodwill	'	'	'	'	'	27,317,000	'	'	'	'
Other non-current assets	'	'	'	'	'	1,843,000	'	'	'	'
Current liabilities	'	'	'	'	'	-9,350,000	'	'	'	'
Debt	'	'	'	'	'	-34,208,000	'	'	'	'
Other long-term liabilities	'	'	'	'	'	-301,000	'	'	'	'
Revenue	'	'	'	'	'	'	'	63,369,000	'	207,878,000
Net loss	'	'	'	'	'	'	'	-13,496,000	'	-48,765,000
Loss per share	'	'	'	'	'	'	'	($0.05)	'	($0.17)
Professional Fees	'	'	'	'	'	'	'	2,048,000	'	3,015,000
Change of Control Agreements	'	'	'	'	'	'	'	2,042,000	'	2,042,000
Acquisition-related	$0	$4,090,000	$967,000	$0	$5,057,000	'	'	$4,090,000	'	$5,057,000

EARNINGS_LOSS_PER_SHARE_Detail

EARNINGS (LOSS) PER SHARE - (Details)	3 Months Ended		9 Months Ended
	Sep. 27, 2013	Sep. 28, 2012	Sep. 27, 2013	Sep. 28, 2012
Reconciliation of weighted average shares outstanding from basic to diluted	'	'	'	'
Weighted average shares outstanding - basic	279,209,000	280,145,000	281,041,000	279,854,000
Potential dilutive common shares	0	0	0	0
Weighted average shares outstanding - diluted	279,209,000	280,145,000	281,041,000	279,854,000
Common stock and unvested shares of restricted stock not included because their effect would have been antidilutive (in shares)	36,000,000	27,600,000	35,900,000	27,200,000

CASH_EQUIVALENTS_MARKETABLE_SE2

CASH EQUIVALENTS, MARKETABLE SECURITIES AND INVESTMENTS - Schedule of Activity for Short-Term Investments (Detail) (USD $)

Sep. 27, 2013

Dec. 31, 2012

Sep. 27, 2013

Sep. 27, 2013

Sep. 27, 2013

Dec. 31, 2012

Sep. 27, 2013

Dec. 31, 2012

Sep. 27, 2013

Dec. 31, 2012

Sep. 27, 2013

Dec. 31, 2012

Sep. 27, 2013

Dec. 31, 2012

In Thousands, unless otherwise specified

Minimum [Member]

Maximum [Member]

U.S. government agency notes [Member]

U.S. government agency notes [Member]

Foreign government notes [Member]

Foreign government notes [Member]

Corporate debt securities [Member]

Corporate debt securities [Member]

Commercial paper [Member]

Commercial paper [Member]

Certificates of deposit [Member]

Certificates of deposit [Member]

Amortized cost, gross unrealized gains and losses and fair value of marketable debt and equity securities and investments

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Cash equivalents, amortized cost

$33,110

$69,389

'

'

'

'

'

'

'

'

'

'

'

'

Cash equivalents, fair value

33,110

69,389

'

'

'

'

'

'

'

'

'

'

'

'

Marketable securities, amortized cost

128,137

161,835

'

'

47,606

53,646

'

2,000

65,241

84,047

11,240

7,492

4,050

14,650

Marketable securities, unrealized gains

61

75

'

'

30

22

'

1

24

34

4

5

3

13

Marketable securities, unrealized losses

-21

-5

'

'

0

0

'

0

-20

-5

0

0

-1

0

Marketable securities, fair value

128,177

161,905

'

'

47,636

53,668

'

2,001

65,245

84,076

11,244

7,497

4,052

14,663

Investments, amortized cost

66,909

29,664

'

'

20,471

19,358

1,250

'

45,188

10,306

'

'

'

'

Investments, unrealized gains

24

40

'

'

8

20

0

'

16

20

'

'

'

'

Investments, unrealized losses

-44

-6

'

'

-3

0

-1

'

-40

-6

'

'

'

'

Investments, fair value

$66,889

$29,698

'

'

$20,476

$19,378

$1,249

'

$45,164

$10,320

'

'

'

'

Period considered to classify available-for-sale securities as investments

'

'

'1 year

'2 years

'

'

'

'

'

'

'

'

'

'

CASH_EQUIVALENTS_MARKETABLE_SE3

CASH EQUIVALENTS, MARKETABLE SECURITIES AND INVESTMENTS - Schedule of Short-Term Investments by Measurement (Detail) (USD $)	Sep. 27, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified
Cash and cash equivalents, Marketable securities and Investments	'	'
Cash equivalents, fair value	$33,110	$69,389
Marketable securities, fair value	128,177	161,905
Investments, fair value	66,889	29,698
Total carrying value [Member]	'	'
Cash and cash equivalents, Marketable securities and Investments	'	'
Cash equivalents, fair value	33,110	69,389
Marketable securities, fair value	128,177	161,905
Investments, fair value	66,889	29,698
Quoted prices in active markets (Level 1) [Member]	'	'
Cash and cash equivalents, Marketable securities and Investments	'	'
Cash equivalents, fair value	33,110	68,389
Marketable securities, fair value	0	0
Investments, fair value	0	0
Significant other observable inputs (Level 2) [Member]	'	'
Cash and cash equivalents, Marketable securities and Investments	'	'
Cash equivalents, fair value	0	1,000
Marketable securities, fair value	128,177	161,905
Investments, fair value	66,889	29,698
Significant unobservable inputs (Level 3) [Member]	'	'
Cash and cash equivalents, Marketable securities and Investments	'	'
Cash equivalents, fair value	0	0
Marketable securities, fair value	0	0
Investments, fair value	0	0
U.S. government agency notes [Member] | Total carrying value [Member]	'	'
Cash and cash equivalents, Marketable securities and Investments	'	'
Marketable securities, fair value	47,636	53,668
Investments, fair value	20,476	19,378
U.S. government agency notes [Member] | Quoted prices in active markets (Level 1) [Member]	'	'
Cash and cash equivalents, Marketable securities and Investments	'	'
Marketable securities, fair value	0	0
Investments, fair value	0	0
U.S. government agency notes [Member] | Significant other observable inputs (Level 2) [Member]	'	'
Cash and cash equivalents, Marketable securities and Investments	'	'
Marketable securities, fair value	47,636	53,668
Investments, fair value	20,476	19,378
U.S. government agency notes [Member] | Significant unobservable inputs (Level 3) [Member]	'	'
Cash and cash equivalents, Marketable securities and Investments	'	'
Marketable securities, fair value	0	0
Investments, fair value	0	0
Foreign government notes [Member] | Total carrying value [Member]	'	'
Cash and cash equivalents, Marketable securities and Investments	'	'
Marketable securities, fair value	'	2,001
Investments, fair value	1,249	'
Foreign government notes [Member] | Quoted prices in active markets (Level 1) [Member]	'	'
Cash and cash equivalents, Marketable securities and Investments	'	'
Marketable securities, fair value	'	0
Investments, fair value	0	'
Foreign government notes [Member] | Significant other observable inputs (Level 2) [Member]	'	'
Cash and cash equivalents, Marketable securities and Investments	'	'
Marketable securities, fair value	'	2,001
Investments, fair value	1,249	'
Foreign government notes [Member] | Significant unobservable inputs (Level 3) [Member]	'	'
Cash and cash equivalents, Marketable securities and Investments	'	'
Marketable securities, fair value	'	0
Investments, fair value	0	'
Corporate debt securities [Member] | Total carrying value [Member]	'	'
Cash and cash equivalents, Marketable securities and Investments	'	'
Marketable securities, fair value	65,245	84,076
Investments, fair value	45,164	10,320
Corporate debt securities [Member] | Quoted prices in active markets (Level 1) [Member]	'	'
Cash and cash equivalents, Marketable securities and Investments	'	'
Marketable securities, fair value	0	0
Investments, fair value	0	0
Corporate debt securities [Member] | Significant other observable inputs (Level 2) [Member]	'	'
Cash and cash equivalents, Marketable securities and Investments	'	'
Marketable securities, fair value	65,245	84,076
Investments, fair value	45,164	10,320
Corporate debt securities [Member] | Significant unobservable inputs (Level 3) [Member]	'	'
Cash and cash equivalents, Marketable securities and Investments	'	'
Marketable securities, fair value	0	0
Investments, fair value	0	0
Commercial paper [Member] | Total carrying value [Member]	'	'
Cash and cash equivalents, Marketable securities and Investments	'	'
Marketable securities, fair value	11,244	7,497
Commercial paper [Member] | Quoted prices in active markets (Level 1) [Member]	'	'
Cash and cash equivalents, Marketable securities and Investments	'	'
Marketable securities, fair value	0	0
Commercial paper [Member] | Significant other observable inputs (Level 2) [Member]	'	'
Cash and cash equivalents, Marketable securities and Investments	'	'
Marketable securities, fair value	11,244	7,497
Commercial paper [Member] | Significant unobservable inputs (Level 3) [Member]	'	'
Cash and cash equivalents, Marketable securities and Investments	'	'
Marketable securities, fair value	0	0
Certificates of deposit [Member] | Total carrying value [Member]	'	'
Cash and cash equivalents, Marketable securities and Investments	'	'
Marketable securities, fair value	4,052	14,663
Certificates of deposit [Member] | Quoted prices in active markets (Level 1) [Member]	'	'
Cash and cash equivalents, Marketable securities and Investments	'	'
Marketable securities, fair value	0	0
Certificates of deposit [Member] | Significant other observable inputs (Level 2) [Member]	'	'
Cash and cash equivalents, Marketable securities and Investments	'	'
Marketable securities, fair value	4,052	14,663
Certificates of deposit [Member] | Significant unobservable inputs (Level 3) [Member]	'	'
Cash and cash equivalents, Marketable securities and Investments	'	'
Marketable securities, fair value	$0	$0

INVENTORY_Details

INVENTORY - (Details) (USD $)	Sep. 27, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified
Inventory Disclosure [Abstract]	'	'
On-hand final assemblies and finished goods inventories	$18,895	$22,009
Deferred cost of goods sold	5,420	5,704
Gross inventory	24,315	27,713
Less current portion	-22,058	-25,614
Noncurrent portion (included in other assets)	$2,257	$2,099

INTANGIBLE_ASSETS_AND_GOODWILL2

INTANGIBLE ASSETS AND GOODWILL - (Details) (USD $)	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 27, 2013	Sep. 28, 2012	Sep. 27, 2013	Sep. 28, 2012	Dec. 31, 2012	Dec. 31, 2011
Intangible Assets And Goodwill	'	'	'	'	'	'
Goodwill, Gross	'	'	'	'	'	$8,168,000
Goodwill, Impaired, Accumulated Impairment Loss	'	'	'	'	'	3,106,000
Weighted average amortization period (years)	'	'	'4 years 4 months 6 days	'	'4 years 4 months 6 days	'
Cost	17,809,000	'	17,809,000	'	19,809,000	'
Accumulated amortization	6,632,000	'	6,632,000	'	4,572,000	'
Net carrying value	11,177,000	'	11,177,000	'	15,237,000	'
Amortization expense	1,087,000	704,000	3,460,000	904,000	'	'
Estimated future amortization expense for intangible assets	'	'	'	'	'	'
2013	1,087,000	'	1,087,000	'	'	'
2014	3,235,000	'	3,235,000	'	'	'
2015	2,367,000	'	2,367,000	'	'	'
2016	1,933,000	'	1,933,000	'	'	'
2017	1,900,000	'	1,900,000	'	'	'
Thereafter	655,000	'	655,000	'	'	'
Total	11,177,000	'	11,177,000	'	'	'
Intellectual Property [Member]	'	'	'	'	'	'
Intangible Assets And Goodwill	'	'	'	'	'	'
Weighted average amortization period (years)	'	'	'5 years	'	'5 years	'
Cost	999,000	'	999,000	'	2,999,000	'
Accumulated amortization	999,000	'	999,000	'	2,199,000	'
Net carrying value	0	'	0	'	800,000	'
Amortization expense	0	100,000	200,000	300,000	'	'
Developed technology [Member]	'	'	'	'	'	'
Intangible Assets And Goodwill	'	'	'	'	'	'
Weighted average amortization period (years)	'	'	'5 years 0 months 11 days	'	'5 years 0 months 11 days	'
Cost	9,080,000	'	9,080,000	'	9,080,000	'
Accumulated amortization	2,229,000	'	2,229,000	'	730,000	'
Net carrying value	6,851,000	'	6,851,000	'	8,350,000	'
Amortization expense	500,000	183,000	1,499,000	183,000	'	'
Customer relationships [Member]	'	'	'	'	'	'
Intangible Assets And Goodwill	'	'	'	'	'	'
Weighted average amortization period (years)	'	'	'5 years 3 months 18 days	'	'5 years 3 months 18 days	'
Cost	6,140,000	'	6,140,000	'	6,140,000	'
Accumulated amortization	2,280,000	'	2,280,000	'	702,000	'
Net carrying value	3,860,000	'	3,860,000	'	5,438,000	'
Amortization expense	526,000	175,000	1,578,000	175,000	'	'
Order backlog [Member]	'	'	'	'	'	'
Intangible Assets And Goodwill	'	'	'	'	'	'
Weighted average amortization period (years)	'	'	'3 months 29 days	'	'3 months 29 days	'
Cost	860,000	'	860,000	'	860,000	'
Accumulated amortization	860,000	'	860,000	'	860,000	'
Net carrying value	0	'	0	'	0	'
Amortization expense	0	216,000	0	216,000	'	'
Internal use software [Member]	'	'	'	'	'	'
Intangible Assets And Goodwill	'	'	'	'	'	'
Weighted average amortization period (years)	'	'	'3 years	'	'3 years	'
Cost	730,000	'	730,000	'	730,000	'
Accumulated amortization	264,000	'	264,000	'	81,000	'
Net carrying value	466,000	'	466,000	'	649,000	'
Amortization expense	61,000	30,000	183,000	30,000	'	'
Research and development [Member]	'	'	'	'	'	'
Intangible Assets And Goodwill	'	'	'	'	'	'
Asset Impairment Charges	$600,000	'	'	'	'	'

INTANGIBLE_ASSETS_AND_GOODWILL3

INTANGIBLE ASSETS AND GOODWILL - (Details 2) (USD $)	9 Months Ended
In Thousands, unless otherwise specified	Sep. 28, 2012	Sep. 27, 2013	Dec. 31, 2012	Dec. 31, 2011
Goodwill [Roll Forward]	'	'	'	'
Goodwill	'	'	'	$8,168
Accumulated impairment losses	'	'	'	-3,106
Goodwill, beginning of period	32,261	32,379	32,379	5,062
Acquisition of NET	27,199	'	'	'
Goodwill, end of period	$32,261	$32,379	$32,379	$5,062

ACCRUED_EXPENSES_Details

ACCRUED EXPENSES - (Details) (USD $)	Sep. 27, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified
Payables and Accruals [Abstract]	'	'
Employee compensation and related costs	$16,640	$15,799
Other	9,327	10,413
Total	$25,967	$26,212

RESTRUCTURING_ACCRUAL_Details

RESTRUCTURING ACCRUAL - (Details) (USD $)

3 Months Ended

9 Months Ended

12 Months Ended

3 Months Ended

9 Months Ended

3 Months Ended

9 Months Ended

3 Months Ended

9 Months Ended

3 Months Ended

Sep. 27, 2013

Sep. 28, 2012

Sep. 27, 2013

Sep. 28, 2012

Dec. 31, 2012

Jun. 28, 2013

Mar. 29, 2013

Sep. 27, 2013

Jun. 28, 2013

Sep. 27, 2013

Sep. 27, 2013

Jun. 28, 2013

Sep. 27, 2013

Sep. 27, 2013

Employee Severance [Member]

Employee Severance [Member]

Employee Severance [Member]

Facilities [Member]

Facilities [Member]

Employee Severance and Facilities [Member]

Employee Severance and Facilities [Member]

Employee Severance and Facilities [Member]

Scenario, Forecast [Member]

Employee Severance and Facilities [Member]

RESTRUCTURING ACCRUAL

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Accrued restructuring

$2,100,000

'

$2,100,000

'

$2,700,000

'

'

'

'

'

'

'

'

'

Restructuring Reserve [Roll Forward]

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Balance at the beginning of the period

'

'

'

'

'

'

1,135,000

1,135,000

'

4,100,000

'

'

5,235,000

'

Restructuring

1,140,000

1,992,000

4,787,000

1,992,000

7,675,000

1,434,000

1,900,000

4,478,000

264,000

309,000

1,200,000

1,700,000

4,787,000

2,000,000

Cash payments

'

'

'

'

'

'

'

-3,435,000

'

-1,102,000

'

'

-4,537,000

'

Balance at the end of the period

'

'

'

'

'

'

'

$2,178,000

'

$3,307,000

$5,485,000

'

$5,485,000

'

DEBT_Details

DEBT - (Details) (USD $)	Sep. 27, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified
Debt Disclosure [Abstract]	'	'
Aggregate principal amounts remaining outstanding	$2,380	$2,380

STOCKHOLDER_RIGHTS_PLAN_Detail

STOCKHOLDER RIGHTS PLAN (Details)	Sep. 27, 2013	Jun. 26, 2013
Class of Warrant or Right [Line Items]	'	'
Minimum percentage of ownership for rights to be exercisable	'	15.00%
Preferred Stock [Member]	'	'
Class of Warrant or Right [Line Items]	'	'
Dividend of right per common stock	'	1
Share of preferred stock issued upon conversion	'	0.001
Exerice price per right	25	'

COMMON_STOCK_REPURCHASES_Detai

COMMON STOCK REPURCHASES (Details) (USD $)	3 Months Ended	9 Months Ended		0 Months Ended
Share data in Millions, unless otherwise specified	Sep. 27, 2013	Sep. 27, 2013	Sep. 28, 2012	Jul. 29, 2013
				Common Stock [Member]
Class of Stock [Line Items]	'	'	'	'
Stock buyback program authorized amount	'	'	'	$100,000,000
Payments for Repurchase of Common Stock	$37,340,000	$37,340,000	$0	'
Stock Repurchased and Retired During Period, Shares	'	10.8	'	'

STOCKBASED_COMPENSATION_PLANS_1

STOCK-BASED COMPENSATION PLANS - (Details) (USD $)

0 Months Ended

1 Months Ended

3 Months Ended

9 Months Ended

3 Months Ended

9 Months Ended

3 Months Ended

9 Months Ended

3 Months Ended

9 Months Ended

3 Months Ended

9 Months Ended

3 Months Ended

9 Months Ended

3 Months Ended

9 Months Ended

0 Months Ended

9 Months Ended

0 Months Ended

1 Months Ended

3 Months Ended

9 Months Ended

Jun. 12, 2013

Feb. 15, 2013

Mar. 29, 2013

Sep. 27, 2013

Sep. 28, 2012

Sep. 27, 2013

Sep. 28, 2012

Sep. 27, 2013

Sep. 28, 2012

Sep. 27, 2013

Sep. 28, 2012

Sep. 27, 2013

Sep. 28, 2012

Sep. 27, 2013

Sep. 28, 2012

Sep. 27, 2013

Sep. 28, 2012

Sep. 27, 2013

Sep. 28, 2012

Sep. 27, 2013

Sep. 28, 2012

Sep. 27, 2013

Sep. 28, 2012

Sep. 27, 2013

Sep. 28, 2012

Sep. 27, 2013

Sep. 28, 2012

Sep. 27, 2013

Sep. 27, 2013

Sep. 27, 2013

Feb. 15, 2013

Sep. 27, 2013

Feb. 15, 2013

Aug. 07, 2012

Feb. 15, 2013

Aug. 07, 2012

Feb. 14, 2013

Sep. 27, 2013

Mar. 29, 2013

Sep. 27, 2013

Sep. 27, 2013

Sep. 27, 2013

executives

executives

Product cost of revenue [Member]

Product cost of revenue [Member]

Product cost of revenue [Member]

Product cost of revenue [Member]

Service cost of revenue [Member]

Service cost of revenue [Member]

Service cost of revenue [Member]

Service cost of revenue [Member]

Research and development [Member]

Research and development [Member]

Research and development [Member]

Research and development [Member]

Sales and marketing [Member]

Sales and marketing [Member]

Sales and marketing [Member]

Sales and marketing [Member]

General and Administrative Expense [Member]

General and Administrative Expense [Member]

General and Administrative Expense [Member]

General and Administrative Expense [Member]

Stock options [Member]

Stock options [Member]

Restricted stock awards [Member]

Performance share awards [Member]

Performance share awards [Member]

Raymond P. Dolan, President and Chief Executive Officer [Member]

Raymond P. Dolan, President and Chief Executive Officer [Member]

Raymond P. Dolan, President and Chief Executive Officer [Member]

Raymond P. Dolan, President and Chief Executive Officer [Member]

Raymond P. Dolan, President and Chief Executive Officer [Member]

Executive Officer [Member]

Executive Officer [Member]

Executive Officer [Member]

Minimum [Member]

Maximum [Member]

Performance share awards [Member]

Performance share awards [Member]

Performance share awards [Member]

Restricted stock awards [Member]

Restricted stock awards [Member]

Restricted stock awards [Member]

Stock-based compensation

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Additional shares authorized for future grant

21,000,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Number of executives

'

8

21

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Percentage of bonus received as common stock

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

100.00%

'

'

'

'

'

'

'

'

'

'

'

Award vesting percentage

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

50.00%

'

'

'

'

'

'

'

'

'

'

'

Conversion factor used to convert a number of shares available for grant into the entity's equity awards

'

'

1.5

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Base salary

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

$500,000

'

'

'

'

'

'

'

'

'

Maximum level of achievement as a percentage of base salary

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

150.00%

'

'

'

'

'

'

'

'

Number of shares

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Outstanding at the beginning of the period (in shares)

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

25,116,398

'

'

'

'

'

'

'

'

'

'

'

'

'

Granted (in shares)

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

13,043,856

'

'

'

'

'

'

'

'

'

'

'

'

'

Exercised (in shares)

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

-1,166,397

'

'

'

'

'

'

'

'

'

'

'

'

'

Forfeited (in shares)

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

-1,398,660

'

'

'

'

'

'

'

'

'

'

'

'

'

Expired (in shares)

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

-2,312,336

'

'

'

'

'

'

'

'

'

'

'

'

'

Outstanding at the end of the period (in shares)

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

33,282,861

33,282,861

'

'

'

'

'

'

'

'

'

'

'

'

'

Vested or expected to vest at the end of the period (in shares)

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

30,487,280

30,487,280

'

'

'

'

'

'

'

'

'

'

'

'

'

Exercisable at the end of the period (in shares)

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

14,228,903

14,228,903

'

'

'

'

'

'

'

'

'

'

'

'

'

Weighted average exercise price

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Outstanding at the beginning of the period (in dollars per share)

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

$3.46

'

'

'

'

'

'

'

'

'

'

'

'

'

Granted (in dollars per share)

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

$2.92

'

'

'

'

'

'

'

'

'

'

'

'

'

Exercised (in dollars per share)

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

$2.01

'

'

'

'

'

'

'

'

'

'

'

'

'

Forfeited (in dollars per share)

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

$2.62

'

'

'

'

'

'

'

'

'

'

'

'

'

Expired (in dollars per share)

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

$4.78

'

'

'

'

'

'

'

'

'

'

'

'

'

Outstanding at the end of the period (in dollars per share)

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

$3.25

$3.25

'

'

'

'

'

'

'

'

'

'

'

'

'

Vested or expected to vest at the end of the period (in dollars per share)

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

$3.29

$3.29

'

'

'

'

'

'

'

'

'

'

'

'

'

Exercisable at the end of the period (in dollars per share)

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

$3.85

$3.85

'

'

'

'

'

'

'

'

'

'

'

'

'

Weighted average remaining contractual life (in years)

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Outstanding at the end of the period

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'7 years 2 months 16 days

'

'

'

'

'

'

'

'

'

'

'

'

'

Vested or expected to vest at the end of the period

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'7 years 0 months 7 days

'

'

'

'

'

'

'

'

'

'

'

'

'

Exercisable at the end of the period

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'4 years 9 months 4 days

'

'

'

'

'

'

'

'

'

'

'

'

'

Aggregate intrinsic value (in dollars)

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Outstanding at the end of the period (in dollars)

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

16,860,000

16,860,000

'

'

'

'

'

'

'

'

'

'

'

'

'

Vested or expected to vest at the end of the period (in dollars)

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

15,294,000

15,294,000

'

'

'

'

'

'

'

'

'

'

'

'

'

Exercisable at the end of the period (in dollars)

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

5,694,000

5,694,000

'

'

'

'

'

'

'

'

'

'

'

'

'

Range of assumptions used in estimating fair value of options

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Risk-free interest rates, minimum

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

1.51%

0.82%

'

'

'

'

'

'

'

'

'

'

'

'

'

Risk-free interest rates, maximum

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

1.71%

1.71%

'

'

'

'

'

'

'

'

'

'

'

'

'

Expected dividends

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

0.00%

0.00%

'

'

'

'

'

'

'

'

'

'

'

'

'

Weighted average volatility

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

57.60%

63.20%

'

'

'

'

'

'

'

'

'

'

'

'

'

Expected life

'

'

'

'4 years 6 months

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'4 years 6 months

'6 years

Weighted average grant date fair value of stock options granted (in dollars per share)

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

$1.58

$1.49

'

'

'

'

'

'

'

'

'

'

'

'

'

Total intrinsic values of stock options exercised (in dollars)

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

398,000

1,185,000

'

'

'

'

'

'

'

'

'

'

'

'

'

Cash received from the exercise of stock options (in dollars)

'

'

'

'

'

2,393,000

151,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

1,056,000

2,393,000

'

'

'

'

'

'

'

'

'

'

'

'

'

Change in unvested restricted stock awards

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Unvested balance at the beginning of the period (in shares)

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

617,203

'

421,348

'

'

'

'

'

'

'

'

'

'

Granted (in shares)

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

1,334,086

'

1,984,500

'

'

183,824

421,348

280,899

33,000

40,000

73,000

'

'

Vested (in shares)

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

-634,514

'

-954,292

'

'

'

'

'

'

'

'

'

'

Forfeited (in shares)

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

-54,039

'

-140,449

'

'

'

'

-140,449

'

'

'

'

'

Unvested balance at the end of the period (in shares)

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

1,262,736

'

1,311,107

'

'

'

'

'

'

'

'

'

'

Weighted average grant-date fair value

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Unvested balance at the end of the period (in dollars per share)

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

$2.45

'

$1.78

'

'

'

'

'

'

'

'

'

'

Granted (in dollars per share)

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

$2.82

'

$2.72

'

'

$2.72

$1.78

'

'

'

'

'

'

Vested (in dollars per share)

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

$2.56

'

$2.58

'

'

'

'

'

'

'

'

'

'

Forfeited (in dollars per share)

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

$2.66

'

$1.78

'

'

'

'

'

'

'

'

'

'

Unvested balance at end of the period (in dollars per share)

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

$2.77

'

$2.62

'

'

'

'

'

'

'

'

'

'

Total fair value (in dollars)

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

1,600,000

'

'

'

'

'

'

'

'

'

'

'

'

Stock-based compensation (in dollars)

'

'

'

4,373,000

2,400,000

13,137,000

6,540,000

46,000

41,000

128,000

130,000

299,000

211,000

761,000

595,000

903,000

524,000

2,402,000

1,773,000

1,313,000

500,000

3,631,000

1,458,000

1,812,000

1,124,000

6,215,000

2,584,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Fair value of the assumed awards attributable to future stock-based compensation expense

'

'

'

$26,700,000

'

$26,700,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Expected period for unrecognized expense

'

'

'

'

'

'3 years

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

MAJOR_CUSTOMERS_Details

MAJOR CUSTOMERS - (Details)	9 Months Ended	3 Months Ended	9 Months Ended		3 Months Ended	9 Months Ended
	Sep. 27, 2013	Sep. 27, 2013	Sep. 27, 2013	Sep. 28, 2012	Sep. 28, 2012	Sep. 27, 2013	Sep. 27, 2013	Sep. 28, 2012	Dec. 31, 2012
	Revenue [Member]	Revenue [Member]	Revenue [Member]	Revenue [Member]	Revenue [Member]	Accounts receivable balance [Member]	Accounts receivable balance [Member]	Accounts receivable balance [Member]	Accounts receivable balance [Member]
	Less than [Member]	Customer [Member]	Customer [Member]	Customer [Member]	Customer [Member]		Customer [Member]	Customer [Member]	Customer [Member]
		AT&T [Member]	AT&T [Member]	AT&T [Member]	Level 3 Communications [Member]		customer		customer
MAJOR CUSTOMERS	'	'	'	'	'	'	'	'	'
Concentration risk, percentage	'	18.00%	17.00%	24.00%	12.00%	'	21.00%	25.00%	'
Number of major customers	'	'	'	'	'	'	1	'	1
Threshold percentage	10.00%	'	'	'	'	10.00%	'	'	'

GEOGRAPHIC_INFORMATION_Summary

GEOGRAPHIC INFORMATION - Summary of Revenue by Geographic Area as a Percentage of Total Revenue (Details) (Revenue [Member], Geographical area [Member])	3 Months Ended		9 Months Ended
	Sep. 27, 2013	Sep. 28, 2012	Sep. 27, 2013	Sep. 28, 2012
Revenue by geographic area and by customer	'	'	'	'
Percentage of total revenue	100.00%	100.00%	100.00%	100.00%
United States [Member]	'	'	'	'
Revenue by geographic area and by customer	'	'	'	'
Percentage of total revenue	66.00%	76.00%	70.00%	75.00%
Europe, Middle East and Africa [Member]	'	'	'	'
Revenue by geographic area and by customer	'	'	'	'
Percentage of total revenue	15.00%	13.00%	12.00%	10.00%
Japan [Member]	'	'	'	'
Revenue by geographic area and by customer	'	'	'	'
Percentage of total revenue	8.00%	'	11.00%	9.00%
Other Asia Pacific [Member]	'	'	'	'
Revenue by geographic area and by customer	'	'	'	'
Percentage of total revenue	7.00%	10.00%	5.00%	5.00%
Other [Member]	'	'	'	'
Revenue by geographic area and by customer	'	'	'	'
Percentage of total revenue	4.00%	1.00%	2.00%	1.00%