EXHIBIT 99.1
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FOR IMMEDIATE RELEASE
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        EXCEL SWITCHING CORPORATION COMPLETES ACQUISITION OF RASCOM, INC.

HYANNIS, MASS. -- MAY 11, 1999 -- Excel Switching Corporation (Nasdaq: XLSW), a
leading provider of open switching platforms for telecommunications networks
worldwide, today announced it has completed the acquisition of RAScom, Inc. of
Salem, N.H..

On April 15, 1999 Excel announced that it had signed a definitive agreement to
acquire privately-held RAScom, Inc., a leading provider of remote access server
(RAS) technology. The acquisition of RAScom will expand Excel's addressable
market by adding data capabilities to its Expandable Switching System (EXS)
product line for the Internet Service Provider (ISP) and Competitive Local
Exchange Carrier (CLEC) markets.

Under the terms of the acquisition, Excel acquired all outstanding shares and
options of RAScom in exchange for approximately 1.1 million shares of Excel
common stock, valued at approximately $24 million. The transaction was accounted
for as a pooling of interests transaction and qualified as a tax-free
reorganization.

ABOUT EXCEL
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Excel Switching Corporation is a leading provider of open switching platforms
for telecommunications networks worldwide. Excel develops, manufactures, markets
and supports a family of open, programmable, carrier-class voice and data
gateways that address the complex needs of network providers. Excel's products
are currently deployed in telecommunications networks worldwide. Visit Excel's
website at http://www.xl.com.
                                     (more)




EXCEL SWITCHING COMPLETES ACQUISITION OF RASCOM                           PAGE 2


NOTE TO INVESTORS:
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This release contains forward-looking statements that are made pursuant to the
Safe Harbor provisions of the Private Securities Litigation Reform Act of 1995.
The forward-looking statements contained in this release are subject to a number
of risks and uncertainties that could cause actual results to differ materially
from the company's expectations. Factors that might cause such a difference
include, but are not limited to, those relating to Excel's highly competitive
market; risks associated with Excel's concentrated product family and new
product introductions; the evolving market for telecommunications services and
rapid technological change; possible delayed or lengthy sales cycles; risks
relating to acquisitions; risks associated with efficiently and effectively
integrating RAScom's product offerings and personnel; risks associated with
international sales; dependence on and concentration of relationships with
application developers, original equipment manufacturers and systems
integrators; Excel's dependence on its proprietary rights; and other risks
identified in the Company's Securities and Exchange Commission filings including
those risks identified in the section entitled "Risk Factors" of the Company's
Annual Report on Form 10-K for the year ended December 31, 1998. Product and
service names used within are trademarks, registered trademarks and service
marks of their respective owners.


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CONTACTS:
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Erica Robinson                                         Deborah Shih
Excel Switching Corporation                            FitzGerald Communications
(508) 862-3000                                         (617) 494-9500
erobinson@xl.com                                       dshih@fitzcomm.com