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                                                                     EXHIBIT 3.1

                     RESTATED CERTIFICATE OF INCORPORATION
                        OF PILOT NETWORK SERVICES, INC.


The undersigned, M. Marketta Silvera and William C. Leetham, hereby certify
that:

1.   They are the duly elected and acting Chief Executive Officer and Secretary,
     respectively, of Pilot Network Services, Inc., a Delaware corporation (the
     "Corporation").

2.   The Certificate of Incorporation of this Corporation was originally filed
     with the Secretary of State of Delaware on July 1, 1998.

3.   The Certificate of  Incorporation of this Corporation shall be restated to
     read in full as follows:

                                   ARTICLE I

The name of the Corporation is Pilot Network Services, Inc.

                                  ARTICLE II

The address of the Corporation's registered office in the State of Delaware is
1013 Centre Road, Wilmington, County of New Castle.  The name of its registered
agent at such address is The Prentice-Hall Corporation System, Inc.

                                  ARTICLE III

(a)  This Corporation is authorized to issue two classes of shares to be
     designated respectively "Common Stock" and "Preferred Stock," and each
     class shall have a par value of $0.001 per share. The total number of
     shares of Common Stock authorized is 40,000,000, and the total number of
     shares of Preferred Stock authorized is 2,000,000.
(b)  Any shares of Preferred Stock may be issued from time to time in one or
     more series. The Board is authorized to determine the designation and the
     number of shares of any such series. The Board is also authorized to
     determine or alter the rights, preferences, privileges and restrictions
     granted to or imposed upon any wholly unissued series of Preferred Stock,
     including, without limitation, the dividend rights (and whether dividends
     are cumulative), conversion rights, if any, voting rights, rights and terms
     of redemption (including sinking fund provisions, if any), redemption price
     and liquidation preferences, and, within the limits and restrictions stated
     in any resolution or resolutions of the Board originally fixing the number
     of shares constituting any series, to increase or decrease (but not below
     the number of shares of such series then outstanding) the number of shares
     of any such series subsequent to the issuance of shares of that series. In
     case the number of shares of any series shall be so decreased, the shares
     constituting such decrease shall resume the status which they had prior to
     the adoption of the resolution originally fixing the number of shares of
     such series.

                                  ARTICLE IV

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

                                   ARTICLE V

The Corporation is to have perpetual existence.


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                                  ARTICLE VI

In furtherance and not in limitation of the powers conferred by statute, the
Board of Directors is expressly authorized to make, adopt, alter, amend or
repeal the Bylaws of the Corporation, subject to the right of the stockholders
entitled to vote with respect thereto to amend or repeal Bylaws made by the
Board of Directors as provided for in this Restated Certificate of
Incorporation.  The affirmative vote of 66-2/3% of the total number of votes of
the then outstanding shares of capital stock of this Corporation entitled to
vote generally in the election of directors, voting together as a single class,
shall be required for the adoption, amendment or repeal of the following
sections of the Corporation's Bylaws:  2.3 (Special Meeting), 2.5 (Advance
Notice of Stockholder Nominees) and 2.6 (Advance Notice of Stockholder Business)
by the stockholders of this Corporation.

                                  ARTICLE VII

The number of directors which shall constitute the whole Board of Directors of
the Corporation shall be as specified in the Bylaws of the Corporation.

                                 ARTICLE VIII

The election of directors need not be by written ballot unless the Bylaws of the
Corporation shall so provide.

                                  ARTICLE IX

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 statute) outside 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.

                                   ARTICLE X

If at any time this Corporation shall have a class of stock registered pursuant
to the provisions of the Securities Exchange Act of 1934, for so long as such
class is so registered, any action by the stockholders of such class must be
taken at an annual or special meeting of stockholders and may not be taken by
written consent.  This provision shall supersede any provision to the contrary
in the Bylaws of the Corporation.

                                  ARTICLE XI

Advance 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.

                                  ARTICLE XII

Notwithstanding any other provisions of this Restated Certificate of
Incorporation or the Bylaws (and notwithstanding the fact that a lesser
percentage may be specified by law, this Restated Certificate of Incorporation
or the Bylaws of this Corporation), the affirmative vote of 66-2/3% of the total
number of the then outstanding shares of capital stock of this Corporation
entitled to vote generally in the election of directors, voting together as a
single class, shall be required to amend or repeal, or to adopt any provision
inconsistent with the purpose or intent of, Articles VI through XIV.  Notice of
any such proposed amendment, repeal or adoption, shall be contained in the
notice of the meeting at which it is to be considered.  Subject to the
provisions set forth herein, this Corporation reserves the right to amend,
alter, change or repeal any provision contained in this Restated Certificate of
Incorporation, in the 


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manner now or hereafter prescribed by statute, and all rights conferred upon
stockholders herein are granted subject to this reservation.

                                 ARTICLE XIII

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 Corporation shall
not be personally liable to the Corporation or its stockholders for monetary
damages for breach of fiduciary duty as a director.  Neither any amendment nor
repeal of this Article XIII, nor the adoption of any provision of this Restated
Certificate of Incorporation inconsistent with this Article XIII, shall
eliminate or reduce the effect of this Article XIII in respect of any matter
occurring, or any cause of action, suit or claim that, but for this Article
XIII, would accrue or arise, prior to such amendment, repeal or adoption of any
inconsistent provision.

                                  ARTICLE XIV

"Listing Event" as used in this Restated Certificate of Incorporation shall mean
the Corporation becoming a "Listed Corporation" within the meaning of Section
301.5 of the California Corporations Code.  For the management of the business
and for the conduct of the affairs of the Corporation, and in further
definition, limitation and regulation of the powers of the Corporation, its
directors and its stockholders or any class thereof, as the case may be, it is
further provided that, effective upon the occurrence of the Listing Event:

(i)   The number of directors which shall constitute the entire Board of
      Directors, and the number of directors in each class, shall be fixed
      exclusively by one or more resolutions adopted from time to time by the
      Board of Directors. Until changed by a resolution of the Board of
      Directors, Class I shall consist of three directors, each of whom shall be
      designated by the Board of Directors, and Class II shall consist of two
      directors, each of whom shall be designated by the Board of Directors.

      The Board of Directors shall be divided into two classes, designated as
      Class I and Class II, 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
      Listing Event, the terms of office of the Class I directors shall expire
      and Class I directors shall be elected for a full term of two years. At
      the second annual meeting of stockholders following the Listing Event, the
      term of office of the Class II directors shall expire and Class II
      directors shall be elected for a full term of two years. At each
      succeeding annual meeting of stockholders, directors shall be elected for
      a full term of two 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.
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(ii)   There shall be no right with respect to shares of stock of the
       Corporation to cumulate votes in the election of directors.

(iii)  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 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 66-2/3% of the
       voting power of the then-outstanding shares of the Voting Stock."

Pursuant to Section 242 and 245 of the General Corporation Law of the State of
Delaware, this Restated Certificate of Incorporation restates and integrates,
but does not further amend, the provisions of this Corporation's Certificate of
Incorporation, and there is no discrepancy between those provisions and the
provisions of this Restated Certificate of Incorporation.  Pursuant to Section
242 and 245 of the General Corporation Law of the State of Delaware, this
Restated Certificate of Incorporation has been duly adopted by written consent
of the Board of Directors of this Corporation without a vote of the
stockholders.

Executed at Alameda, California on September 29, 1998.


                                  /s/ M. Marketta Silvera
                                  -----------------------
                                  M. Marketta Silvera,
                                  Chief Executive Officer


                                  /s/ William C. Leetham
                                  ----------------------
                                  William C. Leetham,
                                  Secretary