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                                   EXHIBIT 3.1

                              AMENDED AND RESTATED
                          CERTIFICATE OF INCORPORATION
                                       OF
                                 INTRUSION INC.
                                FORMERLY KNOWN AS
                               INTRUSION.COM, INC.


                                   ARTICLE ONE

                                      NAME
                                      ----

                  The name of the corporation is Intrusion. Inc. (the
"Corporation").

                                   ARTICLE TWO

                               PERIOD OF DURATION
                               ------------------

                  The period of duration of the Corporation is perpetual or
until dissolved or merged or consolidated in some lawful manner.

                                  ARTICLE THREE

                               PURPOSE AND POWERS
                               ------------------

                  Section 1. PURPOSE. The purpose for which the corporation is
organized is to engage in any lawful acts or activities for which corporations
may be organized under the General Corporation Law of the State of Delaware (the
"DGCL").

                  Section 2. POWERS. Subject to any specific written limitations
or restrictions imposed by the DGCL, by other law, or by this Certificate of
Incorporation, and solely in furtherance thereof, but not in addition to the
purposes set forth in Section 1 of this Article, the Corporation shall have and
exercise all of the powers specified in the DGCL, which powers are not
inconsistent with this Certificate of Incorporation.

                                  ARTICLE FOUR

                  CAPITALIZATION, PREEMPTIVE RIGHTS AND VOTING
                  --------------------------------------------

                  Section 1. AUTHORIZED SHARES. The Corporation shall have
authority to issue two classes of shares to be designated respectively, "Common
Stock" and "Preferred Stock." The total number of shares of capital stock which
the Corporation shall have authority to issue is EIGHTY-FIVE MILLION
(85,000,000), of which EIGHTY MILLION (80,000,000) shall be Common Stock and
FIVE MILLION (5,000,000) shall be Preferred Stock. Each share of Common Stock
shall have a par value of ONE CENT ($.01), and each share of Preferred Stock
shall have a par value of ONE CENT ($.01).

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                  The Preferred Stock authorized by this Certificate of
Incorporation may be issued from time to time in one or more series, at the
discretion of the Board of Directors without Stockholder approval, with each
such series to consist of such number of shares and to have such voting powers
(whether full or limited, or no voting powers) and such designations, powers,
preferences and relative, participating, optional, redemption, conversion,
exchange or other special rights, and such qualifications, limitations or
restrictions thereof, as shall be stated in the resolution or resolutions
providing for the issuance of such series adopted by the Board of Directors
prior to the issuance thereof. The Board of Directors is hereby expressly vested
with the authority, to the fullest extent now or hereafter provided by law, to
adopt any such resolution or resolutions. Each share of any series of Preferred
Stock shall be identical with all other shares of such series, except as to the
date from which dividends, if any, shall accrue.

                  Section 2. PREEMPTIVE RIGHTS. No holder of shares of capital
stock of the Corporation shall, as such holder, have any right to purchase or
subscribe for any capital stock of any class which the Corporation may issue or
sell, whether or not exchangeable for any capital stock of the Corporation of
any class or classes, whether issued out of unissued shares authorized by this
Certificate of Incorporation as originally filed or by any amendment thereof, or
out of shares of capital stock of the Corporation acquired by it after the issue
thereof; nor shall any holder of shares of capital stock of the Corporation, as
such holder, have any right to purchase, acquire or subscribe for any securities
which the Corporation may issue or sell whether or not convertible into or
exchangeable for shares of capital stock of the Corporation of any class or
classes, and whether or not any such securities have attached or appurtenant
thereto warrants, options or other instruments which entitle the holders thereof
to purchase, acquire or subscribe for shares of capital stock of any class or
classes.

                  Section 3. VOTING. In the exercise of voting privileges, each
holder of shares of the Common Stock of the Corporation shall be entitled to one
(1) vote for each share held in his name on the books of the Corporation, and
each holder of any series of Preferred Stock of the Corporation shall have such
voting rights, if any, as shall be specified for such series. In all elections
of Directors of the Corporation, cumulative voting is expressly prohibited. As
such, each holder of shares of capital stock of the Corporation entitled to vote
at the election of Directors shall have the right to vote, in person or by
proxy, all or any portion of such shares for or against each individual Director
to be elected and shall not be entitled to vote for or against any one Director
more than the aggregate number of shares held by such holder which are entitled
to vote on the election of Directors. With respect to any action to be taken by
the Stockholders of the Corporation as to any matter other than the election of
Directors, the affirmative vote of the holders of a majority of the shares of
the capital stock of the Corporation entitled to vote thereon and represented in
person or by proxy at a meeting of the Stockholders at which a quorum is present
shall be sufficient to authorize, affirm, ratify or consent to such action.

                  Section 4. NO STOCKHOLDER ACTION BY CONSENT. Any action
required by the DGCL to be taken by the Stockholders shall be taken only at a
duly called annual or special meeting of the Stockholders at which a quorum is
present, and may not be taken without a meeting, without prior notice, and
without a vote, by a consent or consents in writing setting forth the action so
taken signed by the holder or holders of a majority of the outstanding shares of
the capital stock of the Corporation entitled to vote thereon.

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                                  ARTICLE FIVE

                           REGISTERED OFFICE AND AGENT
                           ---------------------------

                  Section 1. REGISTERED OFFICE. The street address of the
registered office of the Corporation is 1209 Orange Street, Wilmington, New
Castle County, Delaware.

                  Section 2. REGISTERED AGENT. The name of the initial
registered agent of the Corporation at such address is The Corporation Trust
Company.

                                   ARTICLE SIX

                                    DIRECTORS
                                    ---------

                  Section 1. BOARD OF DIRECTORS. The business and affairs of the
Corporation shall be managed by or be under the direction of the Board of
Directors which shall consist of not less than one Director, the exact number of
which shall be determined in accordance with the Bylaws of the Corporation. The
number of Directors of the Corporation may from time to time be changed in
accordance with the Bylaws of the Corporation and the DGCL. A Director shall
hold office until the next annual meeting of the Stockholders of the Corporation
and until his successor shall be elected and shall qualify, subject, however, to
prior death, resignation, retirement, disqualification or removal from office.
Any Director elected to fill a vacancy not resulting from an increase in the
number of Directors shall have the same remaining term as that of his
predecessor. A Director elected by the Board of Directors to fill a newly
created Directorship resulting from an increase in the number of Directors shall
hold office until the next annual meeting of the Stockholders of the Corporation
and until his successor shall be elected and shall qualify.

                  Notwithstanding the foregoing, whenever the holders of any one
or more classes or series of Preferred Stock issued by the Corporation shall
have the right, voting separately by class or series, to elect Directors at an
annual or special meeting of Stockholders, the election, term of office, filling
of vacancies and other features of such Directorships shall be governed by the
terms of the Certificate of Designations applicable thereto, and such Directors
so elected shall not be divided into classes unless expressly provided by such
terms. Further, any such Directors elected by one or more classes or series of
Preferred Stock may be removed at any time, with or without cause (except as
other provided in Section 4 of this Article below), by, and only by, the
affirmative vote of the holders of record of a majority of the outstanding
shares of such class or series given at a special meeting if such Stockholders
called for such purpose.

                  Section 2. LIMITATION ON LIABILITY OF DIRECTORS. Pursuant to
Section 102(b)(7) of the DGCL, 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 (1) for any
breach of the Director's duty of loyalty to the Corporation or its Stockholders;
(2) for acts or omissions not in good faith or which involve intentional
misconduct or a knowing violation of law; (3) under Section 174 of the DGCL; or
(4) for any transaction from which the Director derived an improper personal
benefit. If the DGCL or other applicable provision of Delaware law hereafter is
amended to authorize further elimination or limitation of the liability of
Directors, then the liability of a Director of this Corporation, in addition to
the limitation on

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personal liability provided herein, shall be limited to the fullest extent
permitted by the DGCL or other applicable provision of Delaware law as
amended. Any repeal or modification of this Section 2 by the Stockholders of
this Corporation shall be prospective only and shall not adversely affect any
limitation on the personal liability of a Director of the Corporation existing
at the time of such repeal or modification.

                  Section 3. ELECTION AND REMOVAL OF DIRECTORS. Election of
Directors need not be by written ballot. Any Director or the entire Board of
Directors may be removed, with or without cause, by the holders of a majority of
the shares then entitled to vote at an election of Directors, except as
otherwise provided by law and except if the directors of the Corporation are
ever divided into two or three classes, any Director may be removed only for
cause by the holders of a majority of the shares then entitled to vote at an
election for such class of Directors.

                                  ARTICLE SEVEN

                      SPECIAL POWERS OF BOARD OF DIRECTORS
                      ------------------------------------

                  In furtherance and not in limitation of the powers conferred
under the DGCL, the Board of Directors is expressly authorized:

         1.       To adopt, amend or repeal the Bylaws of the Corporation;

         2.       To authorize and cause to be executed mortgages and liens
upon the real and personal property of the Corporation;

         3.       To set apart out of any of the funds of the Corporation
available for dividends a reserve or reserves for any proper purpose, and to
abolish any such reserve in the manner in which it was created;

         4.       By a majority of the whole board, to designate one or more
committees, each committee to consist of one or more of the Directors of the
Corporation; the board may designate one or more Directors as alternate
members of any committee, who may replace any absent or disqualified member at
any meeting of the committee; any such committee, to the extent provided in
the resolution or in the Bylaws of the Corporation, shall have and may
exercise any or all of the powers of the Board of Directors in the management
of the business and affairs of the Corporation, except to the extent that the
DGCL requires a particular matter to be authorized by the Board of Directors,
and may authorize the seal of the Corporation to be affixed to all papers
which may require it; provided, however, the Bylaws may provide that in the
absence or disqualification of any member of the committee or committees, the
member or members thereof present at any meeting and not disqualified form
voting, whether or not he or they constitute a quorum, may unanimously appoint
another member of the Board of Directors to act at the meeting in the place of
any such absent or disqualified member; and

         5.       When and as authorized by the affirmative vote of the
holders of a majority of the stock issued and outstanding having voting power
given at a Stockholders meeting duly called upon such notice as is required by
statute, to sell, lease or exchange all or substantially all of the property
and assets of the Corporation, including its goodwill and its corporate
franchises, upon such terms and conditions and for such consideration, which
may consist in whole or in part of

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money or property, including shares of stock in, and/or other securities of,
any other corporation or corporations, as the Board of Directors shall deem
expedient and in the best interests of the Corporation.

                                  ARTICLE EIGHT

                           ADDITIONAL POWERS IN BYLAWS
                           ---------------------------

                  The Corporation may in its Bylaws confer powers and
authorities upon the Board of Directors in addition to the foregoing and those
expressly conferred upon them by the DGCL.

                                  ARTICLE NINE

               TRANSACTIONS WITH INTERESTED DIRECTORS AND OFFICERS
               ---------------------------------------------------

                  No contract or transaction between the Corporation and one or
more of its Directors or Officers, or between the Corporation and any other
corporation, partnership, association or other organization in which one or more
of the Directors or Officers of the Corporation are directors, officers or
partners, or have a financial interest, shall be void or voidable solely by
reason of such relationship, or solely because the Director or Officer is
present at or participates in the meeting of the Board of Directors of the
Corporation or committee thereof that authorizes the contract or transaction, or
solely because his or their votes are counted for such purposes, if any one of
the following conditions are met:

         1.       The material facts concerning the relationship or interest
of the Director or Officer and the material facts concerning the contract or
transaction are disclosed or are known to the Board of Directors of the
Corporation or the committee thereof that considers the contract or
transaction, and the Board of Directors of the Corporation or committee
thereof in good faith authorizes the contract or transaction by the
affirmative vote of a majority of the disinterested Directors, even though the
disinterested Directors be less than a quorum; or

         2.       The material facts concerning the relationship or interest
of the Director or Officer and the material facts concerning the contract or
transaction are disclosed or are known to the Stockholders of the Corporation
entitled to vote thereon, and the contract or transaction is specifically
approved in good faith by the Stockholders of the Corporation at any annual or
special meeting of Stockholders called for that purpose; or

         3.       The contract or transaction is fair to the Corporation at
the time it is authorized, approved or ratified by the Board of Directors of
the Corporation, a committee thereof, or the Stockholders of the Corporation.

                  Common or interested Directors may be counted in determining
the presence of a quorum at a meeting or the Board of Directors of the
Corporation or of a committee thereof that authorizes such contract or
transaction.

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                                   ARTICLE TEN

                                 INDEMNIFICATION
                                 ---------------

                  Section 1. MANDATORY INDEMNIFICATION AND ADVANCEMENT OF
EXPENSES. Each person who was or is made a party or is threatened to be made a
party to or is involved in any threatened, pending or completed action, suit or
proceeding, whether civil, criminal, administrative, arbitrative or
investigative, any appeal in such action, suit or proceeding, and any inquiry or
investigation that could lead to such an action, suit, or proceeding (the
"Proceeding"), by reason of the fact that he is or was an Officer or a Director
of the Corporation, or who, while a Director or Officer of the Corporation, is
or was serving at the request of the Corporation as a Director, Officer,
partner, venturer, proprietor, trustee, employee, agent, or similar functionary
of another corporation, partnership, joint venture, sole proprietorship, trust,
employee benefit plan or other enterprise, shall be indemnified and held
harmless by the Corporation to the fullest extent permitted by the DGCL against
all judgments, penalties (including excise and similar taxes), fines,
settlements, and reasonable expenses (including attorneys' fees) actually
incurred by such person in connection with such Proceeding. Such right shall be
a contract right and shall include the right to require advancement by the
Corporation of reasonable expenses (including attorneys' fees) incurred in
defending any such Proceeding in advance of its final disposition; provided,
however, that the payment of such expenses in advance of the final disposition
of such Proceeding shall be made by the Corporation only upon delivery to the
Corporation of a written affirmation by such person of his good faith belief
that he has met the standard of conduct necessary for indemnification under the
DGCL and a written undertaking, by or on behalf of such person, to repay all
amounts so advanced if it should be ultimately determined that such person has
not satisfied such requirements.

                  Section 2. NATURE OF INDEMNIFICATION. The indemnification and
advancement of expenses provided for herein shall not be deemed exclusive of any
rights permitted by law to which a person seeking indemnification may be
entitled under any Bylaw, agreement, vote of Stockholders or otherwise, and
shall continue as to a person who has ceased to be a Director or Officer of the
Corporation and shall inure to the benefit of the heirs, executors and
administrators of such a person.

                  Section 3. INSURANCE. The Corporation shall have power to
purchase and maintain insurance or another arrangement on behalf of any person
who is or was a Director, Officer, employee or agent of the Corporation, or is
or was serving at the request of the Corporation as a Director, Officer,
partner, venturer, proprietor, trustee, employee, agent, or similar functionary
of another corporation, partnership, joint venture, sole proprietorship, trust,
employee benefit plan or other enterprise against any liability asserted against
him and incurred by him in any such capacity, or arising out of his status as
such, whether or not the Corporation would have the power to indemnify him
against such liability under the provisions of this Article or the DGCL.

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                                 ARTICLE ELEVEN

                           ARRANGEMENT WITH CREDITORS
                           --------------------------

                  Whenever a compromise or arrangement is proposed between this
Corporation and its creditors or any class of them and/or between this
Corporation and its Stockholders or any class of them, any court of equitable
jurisdiction within the State of Delaware may, on the application in a summary
way of this Corporation or of any creditor or Stockholder thereof or on the
application of any receiver or receivers appointed for this Corporation under
the provisions of Section 291 of Title 8 of the Delaware Code, or on the
application of trustees in dissolution or of any receiver or receivers appointed
for this Corporation under the provisions of Section 279 of Title 8 of the
Delaware Code, order a meeting of the creditors or class of creditors, and/or of
the Stockholders or class of Stockholders of this Corporation, as the case may
be, to be summoned in such manner as the said court directs. If a majority in
number representing three-fourths in value of the creditors or class of
creditors, and/or of the Stockholders or class of Stockholders of this
Corporation, as the case may be, agree to any compromise or arrangement and to
any reorganization of this Corporation as a consequence of such compromise or
arrangement, the said compromise or arrangement and the said reorganization
shall, if sanctioned by the court to which the said application has been made,
be binding on all the creditors or class of creditors, and/or on all the
Stockholders or class of Stockholders, of this Corporation, as the case may be,
and also on this Corporation.

                                 ARTICLE TWELVE

                               AMENDMENT OF BYLAWS
                               -------------------

                  The Board of Directors of the Corporation shall have the power
to adopt, alter, amend or repeal the Bylaws of the Corporation. Notwithstanding
the preceding, the Stockholders of the Corporation shall also have the power to
adopt, alter, amend or repeal the Bylaws of the Corporation.

                                ARTICLE THIRTEEN

                                   AMENDMENTS
                                   ----------

                  The Corporation reserves the right to amend, alter, change or
repeal any provision continued in this Certificate of Incorporation or in its
Bylaws in the manner now or hereafter prescribed by the DGCL or this Certificate
of Incorporation, and all rights conferred on Stockholders herein are granted
subject to this reservation.

                                ARTICLE FOURTEEN

                                    CAPTIONS
                                    --------

                  The captions used in this Certificate of Incorporation are for
convenience only and shall not be construed in interpreting the provisions
hereof.