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                                                                     Exhibit 3.3

                      RESTATED CERTIFICATE OF INCORPORATION
                                       OF
                         TIPPINGPOINT TECHNOLOGIES, INC.

                                    PREAMBLE

     This restated certificate of incorporation for TippingPoint Technologies,
Inc., a Delaware corporation (originally incorporated as Netpliance, Inc. on
February 10, 2000), having been duly adopted pursuant to ss.245 of the GCL (as
defined below) by the Board of Directors, restates and integrates and does not
further amend the provisions of the corporation's certificate of incorporation
as heretofore amended or supplemented, and contains no discrepancy between those
provisions and the provisions of this restated certificate.

                                   ARTICLE I

     The name of the corporation is TippingPoint Technologies, Inc. (the
"Corporation").

                                   ARTICLE II

     The name of the Corporation's registered agent and the address of its
registered office in the State of Delaware is Corporation Service Company, 1013
Centre Road, Wilmington, New Castle County, Delaware 19805.

                                  ARTICLE III

     The purpose of the Corporation is to engage in any lawful act or activity
for which corporations may be organized under the General Corporation Law of the
State of Delaware ("GCL").

                                   ARTICLE IV

     The total number of shares of capital stock which the Corporation shall
have the authority to issue is two hundred fifty-five million (255,000,000)
shares divided into two classes, of which two hundred fifty million
(250,000,000) shares shall be Common Stock with a par value of $0.01 per share
and five million (5,000,000) shares shall be designated as Preferred Stock with
a par value of $0.01 per share.

     A.   Preferred Stock.  The board of directors is expressly authorized to
          ---------------
provide for the issue of all or any shares of the Preferred Stock, in one or
more series, and to fix for each such series such designations, powers,
preferences and rights and such qualifications, limitations or restrictions
thereof, as shall be stated and expressed in the resolution or resolutions
adopted by the board of directors providing for the issue of such series (a
"Preferred Stock Designation") and

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as may be permitted by the GCL. The number of authorized shares of Preferred
Stock may be increased or decreased (but not below the number of shares thereof
then outstanding) by the affirmative vote of the holders of a majority of the
voting power of all of the then outstanding shares of the capital stock of the
Corporation entitled to vote generally in the election of directors (the
"Voting Stock"), voting together as single class, without a separate vote of the
holders of the Preferred Stock, or any series thereof, unless a vote of any such
holders is required pursuant to any Preferred Stock Designation.

     B.   Common Stock. Except as otherwise required by law or as otherwise
          ------------
provided in any Preferred Stock Designation, the holders of the Common Stock
shall exclusively possess all voting rights and powers and the holders of the
Common Stock shall have one vote for each share of Common Stock held of record.


                                   ARTICLE V

     The board of directors is expressly authorized to adopt, amend or repeal
the by-laws of the Corporation. Any by-laws made by the directors under the
powers conferred hereby may be amended or repealed by the directors or by the
stockholders. Notwithstanding the foregoing and anything contained in this
Certificate of Incorporation to the contrary, the by-laws shall not be amended
or repealed by the stockholders, and no provision inconsistent therewith shall
be adopted by the stockholders, without the affirmative vote of the holders of
at least 80% of the Voting Stock.


                                   ARTICLE VI

     The business and affairs of the Corporation shall be managed by or under
the direction of the board of directors. The board of directors may exercise all
such authority and powers of the Corporation and do all such lawful acts and
things as are not by statute or this Certificate of Incorporation directed or
required to be exercised or done by the shareholders. Directors need not be
elected by written ballot unless the Bylaws of the otherwise provide.

     A.   Number of Directors

     The number of directors constituting the initial board of directors is one
(1). The number of directors of the Corporation shall be fixed from time to time
by action of not less than a majority of the members of the board of directors
then in office, though less than a quorum, but in no event shall be less than
one (1) nor more than fifteen (15).

     B.   Vacancies

     Subject to the rights, if any, of the holders of any series of Preferred
Stock then outstanding, newly created directorships resulting from any increase
in the authorized number of directors or any vacancies in the board of directors
resulting from death, resignation, disqualification or removal may be filled
only by a majority vote of the directors then in office

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(and not by the stockholders), though less than a quorum, and directors so
chosen shall hold office for a term expiring at the next annual meeting of
stockholders and until such director's successor shall have been duly elected
and qualified.

     C.   Removal

     Subject to the rights, if any, of any series of Preferred Stock then
outstanding, any director, or the entire board of directors, may be removed from
office at any time, with or without cause and only by the affirmative vote of
the holders of at least 80% of the shares of Voting Stock.


                                  ARTICLE VII

     Nominations of persons for election to the board of directors may be made
at an annual meeting of stockholders or special meeting of stockholders called
by the board of directors for the purpose of electing directors (i) by or at the
direction of the board of directors or (ii) by any stockholder of the
Corporation entitled to vote for the election of directors at such meeting who
complies with the notice procedures set forth in this Article VII. Such
nominations, other than those made by or at the direction of the board of
directors, shall be made pursuant to timely notice in writing to the Secretary
of the Corporation. To be timely, a stockholder's notice must be delivered to or
mailed and received at the principal executive offices of the Corporation not
less than 90 days nor more than 120 days prior to the scheduled date of the
meeting, regardless of any postponement, deferral or adjournment of that meeting
to a later date; provided, however, that if less than 70 days' notice or prior
public disclosure of the date of the meeting is given or made to stockholders,
notice by the stockholder to be timely must be so delivered or received not
later than the close of business on the 10th day following the earlier of (i)
the day on which such notice of the date of the meeting was mailed or (ii) the
day on which such public disclosure was made.

     A stockholder's notice to the Secretary shall set forth: (i) as to each
person whom the stockholder proposes to nominate for election or reelection as a
director (a) the name, age, business address and residence address of such
person, (b) the principal occupation or employment of such person, (c) the class
and number of shares of the Corporation that are beneficially owned by such
person on the date of such stockholder's notice and (d) any other information
relating to such person that is required to be disclosed in solicitations of
proxies for election of directors, or is otherwise required, in each case
pursuant to Regulation 14A under the Securities Exchange Act of 1934, as
amended, or any successor statute thereto (the "Exchange Act") (including,
without limitation, such person's written consent to being named in the proxy
statement as a nominee and to serving as a director if elected); (ii) as to the
stockholder giving notice (a) the name and address, as such information appears
on the Corporation's books, of such stockholder and any other stockholders known
by such stockholder to be supporting such nominee(s), (b) the class and number
of shares of the Corporation which are beneficially owned by such stockholder
and each other stockholder known by such stockholder to be supporting such
nominee(s) on the date of such stockholders notice, (c) a representation that
the stockholder is a holder of record of stock of the Corporation entitled to
vote at such meeting and intends to


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appear in person or by proxy at the meeting to nominate the person or persons
specified in the notice; and (iii) a description of all arrangements or
understandings between the stockholder and each nominee and other person or
persons (naming such person or persons) pursuant to which the nomination or
nominations are to be made by the stockholder.

     Subject to the rights, if any, of the holders of any series of Preferred
Stock then outstanding, no person shall be eligible for election as a director
of the Corporation unless nominated in accordance with the procedures set forth
in this Article VII. The chairperson of the meeting shall, if the facts warrant,
determine and declare to the meeting that a nomination was not made in
accordance with the procedures prescribed by this Article VII and if the
chairperson should so determine, the chairperson shall so declare to the meeting
and the defective nomination shall be disregarded.


                                  ARTICLE VIII

     Except as provided in a Preferred Stock Designation with respect to a
series of Preferred Stock, any action required or permitted to be taken by the
stockholders of the Corporation must be effected at a duly called annual or
special meeting of the stockholders of the Corporation and may not be effected
by consent in writing of the stockholders. At an annual meeting of stockholders,
only such business shall be conducted, and only such proposals shall be acted
upon, as shall have been properly brought before the annual meeting of
stockholders (a) by or at the direction of the board of directors or (b) by a
stockholder of the Corporation who complies with the procedures set forth in
this Article VIII. For business or a proposal to be properly brought before an
annual meeting of stockholders by a stockholder, the stockholder must have given
timely notice thereof in writing to the Secretary of the Corporation. To be
timely, a stockholder's notice must be delivered to or mailed and received at
the principal executive offices of the Corporation not less than 90 days nor
more than 120 days prior to the scheduled date of the annual meeting, regardless
of any postponement, deferral or adjournment of that meeting to a later date;
provided, however, that if less than 70 days' notice or prior public disclosure
of the date of the annual meeting is given or made to stockholders, notice by
the stockholder to be timely must be so delivered or mailed and received not
later than the close of business on the 10th day following the earlier of (i)
the day on which such notice of the date of the meeting was mailed or (ii) the
day on which such public disclosure was made.

     A stockholder's notice to the Secretary shall set forth as to each matter
the stockholder proposes to bring before an annual meeting of stockholders (i) a
description, in 500 words or less, of the business desired to be brought before
the annual meeting and the reasons for conducting such business at the annual
meeting, (ii) the name and address, as such information appears on the
Corporation's books, of the stockholder proposing such business and any other
stockholders known by such stockholder to be supporting such proposal, (iii) the
class and number of shares of the Corporation which are beneficially owned by
such stockholder and each other stockholder known by such stockholder to be
supporting such proposal on the date of such stockholder's notice, (iv) a
description, in 500 words or less, of any interest of the stockholder in such
proposal and (v) a representation that the stockholder is a holder of record of
stock of the

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Corporation and intends to appear in person or by proxy at the meeting to
present the proposal specified in the notice.

     The chairman of the meeting shall, if the facts warrant, determine and
declare to the meeting that the business was not properly brought before the
meeting in accordance with the procedures prescribed by this Article VIII, and
if he should so determine, he shall so declare to the meeting and any such
business not properly brought before the meeting shall not be transacted.
Notwithstanding the foregoing, nothing in this Article VIII shall be interpreted
or construed to require the inclusion of information about any such proposal in
any proxy statement distributed by, at the direction of, or on behalf of, the
board of directors.


                                   ARTICLE IX

     A.   Right to Indemnification

     Each person who was or is made a party or is threatened to be made a party
to or is otherwise involved in any action, suit or proceeding, whether civil,
criminal, administrative or investigative (hereinafter a "proceeding"), by
reason of the face that he or she is or was a director or officer of the
Corporation or is or was serving at the request of the Corporation as a
director, officer, employee or agent of another corporation or of a partnership,
joint venture, trust or other enterprise, including service with respect to
employee benefit plans (hereafter an "Indemnitee"), whether the basis of such
proceeding is alleged action in an official capacity as a director, officer,
employee or agent or in any other capacity while serving as a director, officer,
employee or agent, shall be indemnified and held harmless by the Corporation to
the fullest extent authorized by the GCL, as the same exists or may hereafter be
amended (but, in the case of any such amendment, only to the extent that such
amendment permits the Corporation to provide broader indemnification rights than
such law permitted the Corporation to provide prior to such amendment) against
all expense, liability and loss (including attorneys' fees, judgments, fines,
ERISA excise taxes or penalties and amounts paid in settlement) reasonably
incurred or suffered by such Indemnitee in connection therewith and such
indemnification shall continue as to an Indemnitee who has ceased to be a
director, officer, employee or agent and shall inure to the benefit of the
Indemnitee's heirs, executors and administrators; provided, however, that,
                                                  --------  -------
except as provided in paragraph (B) hereof with respect to proceedings to
enforce rights to indemnification and payment of expenses, the Corporation shall
indemnify any such Indemnitee in connection with a proceeding (or part thereof)
initiated by such Indemnitee only if such proceeding (or part thereof) was
authorized by the board of directors of the Corporation. The right to
indemnification conferred in this Article shall be a contract right and shall
include the right to be paid by the Corporation the expenses (including
attorneys' fees) incurred in defending any such proceeding in advance of its
final disposition; provided, however, that, if the GCL requires, the payment of
                   --------  -------
such expenses incurred by an Indemnitee in his or her capacity as a director or
officer (and not in any other capacity in which service was or is rendered by
such Indemnitee, including, without limitation, service to an employee benefit
plan) in advance of the final disposition of a proceeding, shall be made only
upon delivery to the Corporation of an undertaking, by or on behalf of such
Indemnitee, to repay all amounts so advanced if it shall ultimately be
determined by final judicial decision from which there is no further right to
appeal

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that such Indemnitee is not entitled to be indemnified such expenses under this
section or otherwise.

     B.   Right of Indemnitee to Bring Suit.

     If a claim under paragraph (A) of this Article is not paid in full by the
Corporation within sixty days after a written claim has been received by the
Corporation, except in the case of a claim for expenses incurred in defending a
proceeding in advance of its final disposition, in which case the applicable
period shall be twenty days, the Indemnitee may at any time thereafter bring
suit against the Corporation to recover the unpaid amount of the claim. If
successful in whole or in part in any such suit or in a suit brought by the
Corporation to recover payments by the Corporation of expenses incurred by an
Indemnitee in defending, in his or her capacity as a director or officer, a
proceeding in advance of its final disposition, the Indemnitee shall be entitled
to be paid also the expense of prosecuting or defending such claim. In any
action brought by the Indemnitee to enforce a right to indemnification hereunder
(other than an action brought to enforce a claim for expenses incurred in
defending any proceeding in advance of its final disposition where the required
undertaking, if any, has been provided to the Corporation) or by the Corporation
to recover payments by the Corporation of expenses incurred by an Indemnitee in
defending, in his or her capacity as a director or officer, a proceeding in
advance of its final disposition, the burden of proving that the Indemnitee is
not entitled to be indemnified under this Article or otherwise shall be on the
Corporation. Neither the failure of the Corporation (including its board of
directors, independent legal counsel, or its stockholders) to have made a
determination prior to the commencement of such action that indemnification of
the Indemnitee is proper in the circumstances because the Indemnitee has met the
applicable standard of conduct set forth in the GCL, nor an actual determination
by the Corporation (including its board of directors, independent legal counsel,
or its stockholders) that the Indemnitee has not met such applicable standard of
conduct, shall create a presumption that the Indemnitee has not met the
applicable standard of conduct or, in the case of such an action brought by the
Indemnitee, be a defense to the action.

     C.   Non-Exclusivity of Rights.

     The right to indemnification and the payment of expenses incurred in
defending a proceeding in advance of its final disposition conferred in this
Article shall not be exclusive of any other right which any person may have or
hereafter acquire under any statute, this Certificate of Incorporation, by-law,
agreement, vote of stockholders or disinterested directors or otherwise.

     D.   Insurance.

     The Corporation may maintain insurance, at its expense, to protect itself
and any director, officer, employee or agent of the Corporation or another
corporation, partnership, joint venture, trust or other enterprise against any
expense, liability or loss, whether or not the Corporation would have the power
to indemnify such person against such expense, liability or loss under the GCL.

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     E.   Indemnification of Employees and Agents of the Corporation.

     The Corporation may, to the extent authorized from time to time by the
board of directors, grant rights to indemnification, and to be paid by the
Corporation the expenses incurred in defending any proceeding in advance of Its
final disposition, to any employee or agent of the Corporation to the fullest
extent of the provisions of this Article with respect to the indemnification and
advancement of expenses of directors and officers of the Corporation.


                                   ARTICLE X

     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, except for liability (i) for any breach of the director's
duty of loyalty to the Corporation or its stockholders, (ii) for acts or
omissions not in good faith or which involve intentional misconduct or a knowing
violation of law, (iii) under Section 174 of the GCL, or (iv) for any
transaction from which the director derived any improper personal benefit. If
the GCL is amended to authorize corporate action further eliminating or limiting
the personal liability of directors, then the liability of a director of the
Corporation shall be eliminated or limited to the fullest extent permitted by
the GCL, as so amended. Any repeal or modification of this provision shall not
adversely affect any right or protection of a director of the Corporation
existing at the time of such repeal or modification.


                                   ARTICLE XI

     Subject to the rights of the holders of any series of Preferred Stock,
special meetings of the stockholders, unless otherwise prescribed by statute,
may be called at any time only by the Chairman of the Board of the Corporation
or the board of directors pursuant to a resolution adopted by a majority of the
entire board of directors, which constitutes the total number of directors which
the Corporation would have if there were no vacancies on the board of directors.


                                  ARTICLE XII

     The Corporation reserves the right to amend, add, alter, change repeal or
adopt any provision contained in the Certificate of Incorporation, in the manner
now or hereafter prescribed by statute, and all rights conferred upon
stockholders herein are granted subject to this reservation. In addition to any
affirmative vote required by applicable law or any other provision of the
Certificate of Incorporation or specified in any agreement, and in addition to
any voting rights granted to or held by the holders or any series of Preferred
Stock, the affirmative vote of the holders of not less than 80% of the Voting
Stock shall be required to amend, add, alter, change, repeal or adopt any
provisions inconsistent with Articles IV, VI, VII, VIII, IX, XI and XII of the
Certificate of Incorporation.

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     IN WITNESS WHEREOF, the undersigned authorized officer of the Corporation
hereby certifies that the facts herein stated are true, and accordingly has
signed this instrument this 29th day of October, 2001.

                                        /s/ JAMES E. CAHILL
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                                        James E. Cahill, Vice President and
                                        General Counsel

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