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                                                                     EXHIBIT 3.1

                AMENDED AND RESTATED CERTIFICATE OF INCORPORATION
                                       OF
                             JUNIPER NETWORKS, INC.



       Juniper Networks, Inc., a corporation organized and existing under the
laws of the State of Delaware (the "Corporation"), hereby certifies that:

       A. The name of this Corporation is Juniper Networks, Inc.

       B. The date of filing of this Corporation's original Certificate of
Incorporation with the Secretary of State of Delaware was September 10, 1997.

       C. Pursuant to Sections 241 and 245 of the Delaware General Corporation
law, this Restated Certificate of Incorporation restates, integrates and amends
the provisions of the Corporation's Amended and Restated Certificate of
Incorporation as follows:

       FIRST: The name of this Corporation is Juniper Networks, Inc.

       SECOND: The address of the Corporation's registered office in the State
of Delaware is 1209 Orange Street, Wilmington, County of New Castle, Delaware
19801. The name of its registered agent at such address is The Corporation Trust
Company.

       THIRD: The purpose of this Corporation is to engage in any lawful act or
activity for which corporations may be organized under the General Corporation
Law of Delaware.

       FOURTH: This Corporation is authorized to issue two classes of shares to
be designated, respectively, Common Stock and Preferred Stock. The total number
of shares of Common Stock that this corporation is authorized to issue is
1,000,000,000, with a par value of $0.00001, and the total number of shares of
Preferred stock which this corporation is authorized to issue is 10,000,000,
with a par value of $0.00001.

              The Preferred Stock may be issued from time to time in one or more
series pursuant to a resolution or resolutions providing for such issue duly
adopted by the Board of Directors (authority to do so being hereby expressly
vested in the Board). The Board of Directors is further authorized to determine
or alter the rights, preferences, privileges and restrictions granted to or
imposed upon any wholly unissued series of Preferred Stock and, to fix the
number of shares of any such series of Preferred Stock and the designation of
any such series of Preferred Stock. The Board of Directors is authorized, within
the limits and restrictions stated in any resolution or resolutions of the Board
of Directors originally fixing the number of shares constituting any series, to
increase or decrease (but not below the number of shares then outstanding) the
number of shares of any such series subsequent to the issue of shares of that
series, to determine the designation of any series, and to fix the number of
shares of any series.

       FIFTH: The Corporation is to have perpetual existence.

       SIXTH: Elections of directors need not be by written ballot unless a
stockholder demands election by written ballot at the meeting and before voting
begins or unless the Bylaws of the Corporation shall so provide.
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       SEVENTH: The management of the business and the conduct of the affairs of
the Corporation shall be vested in its Board of Directors. The number of
directors which shall constitute the whole Board of Directors shall be
designated in the Bylaws of the Corporation.

       The Board of Directors shall be divided into three classes designated as
Class I, Class II, and Class III, respectively. Directors shall be assigned to
each class in accordance with a resolution or resolutions adopted by the Board
of Directors. At the first annual meeting of stockholders following the date
hereof, the term of office of the Class I directors shall expire, and Class I
directors shall be elected for a full term of three years. At the second annual
meeting of stockholders following the date hereof, the term of office of the
Class II directors shall expire, and Class II directors shall be elected for a
full term of three years. At the third annual meeting of stockholders following
the date hereof, the term of office of the Class III directors shall expire, and
Class III directors shall be elected for a full term of three years. At each
succeeding annual meeting of stockholders, directors shall be elected for a full
term of three years to succeed the directors of the class whose terms expire at
such annual meeting.

       Notwithstanding the foregoing provisions of this Article, each director
shall serve until his or her successor is duly elected and qualified or until
his or her death, resignation, or removal. No decrease in the number of
directors constituting the Board of Directors shall shorten the term of any
incumbent director.

       Any vacancies on the Board of Directors resulting from death,
resignation, disqualification, removal, or other causes shall be filled by
either (i) the affirmative vote of the holders of a majority of the voting power
of the then-outstanding shares of voting stock of the Corporation entitled to
vote generally in the election of directors (the "Voting Stock") voting together
as a single class; or (ii) by the affirmative vote of a majority of the
remaining directors then in office, even though less than a quorum of the Board
of Directors. Newly created directorships resulting from any increase in the
number of directors shall, unless the Board of Directors determines by
resolution that any such newly created directorship shall be filled by the
stockholders, be filled only by the affirmative vote of the directors then in
office, even though less than a quorum of the Board of Directors. Any director
elected in accordance with the preceding sentence shall hold office for the
remainder of the full term of the class of directors in which the new
directorship was created or the vacancy occurred and until such director's
successor shall have been elected and qualified.

       The affirmative vote of sixty-six and two-thirds percent (66-2/3%) of the
voting power of the then outstanding shares of Voting Stock, voting together as
a single class, shall be required for the adoption, amendment or repeal of the
following sections of the Corporation's Bylaws by the stockholders of the
Corporation: 2.2 (Annual Meeting) and 2.3 (Special Meeting).

       No action shall be taken by the stockholders of the Corporation except at
an annual or special meeting of the stockholders called in accordance with the
Bylaws.

       Any director, or the entire Board of Directors, may be removed from
office at any time (i) with cause by the affirmative vote of the holders of at
least a majority of the voting power of all of the then-outstanding shares of
the Voting Stock, voting together as a single class; or (ii) without cause by
the affirmative vote of the holders of at least sixty-six and two-thirds percent
(66-2/3%) of the voting power of all of the then-outstanding shares of the
Voting Stock.

       EIGHTH: A. To the fullest extent permitted by the Delaware General
Corporation Law as the same exists or as may hereafter be amended, a director of
the


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Corporation or any subsidiary of the Corporation shall not be personally liable
to the Corporation or its stockholders and shall otherwise be indemnified by the
Corporation for monetary damages for breach of fiduciary duty as a director of
the Corporation, any predecessor of the Corporation or any subsidiary of the
Corporation.

       B. The Corporation shall indemnify to the fullest extent permitted by law
any person made or threatened to be made a party to an action or proceeding,
whether criminal, civil, administrative or investigative, by reason of the fact
that he, his testator or intestate is or was a director or officer of the
Corporation, any predecessor of the Corporation or any subsidiary of the
Corporation or serves or served at any other enterprise as a director or officer
at the request of the Corporation, any predecessor to the Corporation or any
subsidiary of the Corporation.

       C. Neither any amendment nor repeal of this Article EIGHTH, nor the
adoption of any provision of the Corporation's Certificate of Incorporation
inconsistent with this Article EIGHTH, shall eliminate or reduce the effect of
this Article EIGHTH, in respect of any matter occurring, or any action or
proceeding accruing or arising or that, but for this Article EIGHTH, would
accrue or arise, prior to such amendment, repeal, or adoption of an inconsistent
provision.

       NINTH: Notwithstanding any other provisions of this Certificate of
Incorporation or any provision of law which might otherwise permit a lesser vote
or no vote, but in addition to any affirmative vote of the holders of any
particular class or series of the Voting Stock required by law, this Certificate
of Incorporation or any rights of designation of Preferred Stock conferred on
the Board of Directors pursuant to Article FOURTH, the affirmative vote of the
holders of at least sixty-six and two-thirds percent (66-2/3%) of the voting
power of all of the then outstanding shares of the Voting Stock, voting together
as a single class, shall be required to alter, amend or repeal Article SEVENTH
or this Article NINTH.

       TENTH: The Corporation reserves the right to amend, alter, change or
repeal any provision contained in this Certificate of Incorporation, in the
manner now or hereafter prescribed by statute, except as provided in Article
NINTH of this Certificate, and all rights conferred upon the stockholders herein
are granted subject to this right.

       ELEVENTH: In furtherance and not in limitation of the powers conferred by
statute, the Board of Directors is expressly authorized to make, alter, amend or
repeal the Bylaws of the Corporation.

       TWELFTH: Meetings of stockholders may be held within or without the State
of Delaware, as the Bylaws may provide. The books of the Corporation may be kept
(subject to any provision contained in the statutes) outside of the State of
Delaware at such place or places as may be designated from time to time by the
Board of Directors or in the Bylaws of the Corporation.

       THIRTEENTH: Advance written notice of new business and stockholder
nominations for the election of directors shall be given in the manner and to
the extent provided in the Bylaws of the Corporation.

       FOURTEENTH: Stockholders shall not be entitled to cumulative voting
rights for the election of directors.


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       IN WITNESS WHEREOF, Juniper Networks, Inc. has caused this Amended and
Restated Certificate of Incorporation to be signed by Scott Kriens, its
President, and attested by Lisa C. Berry, its Secretary, this 4th day of May,
2000.

                                        JUNIPER NETWORKS, INC.

                                             /s/ Scott Kriens
                                        ----------------------------------------
                                        Scott Kriens, President


ATTESTED:


/s/ Lisa C. Berry
- ---------------------------------
Lisa C. Berry, Secretary


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       This Amended and Restated Certificate of Incorporation has been duly
adopted by the stockholders of the Corporation in accordance with the provisions
of Sections 242 and 245 of the General Corporation Law of the State of Delaware,
as amended.


       IN WITNESS WHEREOF, Juniper Networks, Inc. has caused this Amended and
Restated Certificate of Incorporation to be signed by Scott Kriens, its
President, and attested by Lisa C. Berry, its Secretary, this 4th day of May,
2000.

                                        JUNIPER NETWORKS, INC.


                                             /s/ Scott Kriens
                                        ----------------------------------------
                                        Scott Kriens, President


ATTESTED:


     /s/ Lisa C. Berry
- ----------------------------------
Lisa C. Berry, Secretary