<PAGE>
                                                                    Exhibit 10.1


                          PLAN AND AGREEMENT OF MERGER

                                      AMONG

                              I-SECTOR CORPORATION,

                              INX MERGER SUB, INC.

                                       AND

                           INTERNETWORK EXPERTS, INC.

                          DATED AS OF FEBRUARY 1, 2005
<PAGE>
                                TABLE OF CONTENTS

<TABLE>
<CAPTION>
                                                                            PAGE
                                                                            ----
<S>                                                                         <C>
                                    ARTICLE 1
                                   THE MERGER

Section 1.1    The Merger......................................................2
Section 1.2    The Closing.....................................................2
Section 1.3    Effective Time..................................................2
Section 1.4    Effects of the Merger...........................................2

                                    ARTICLE 2
                          ORGANIZATIONAL DOCUMENTS AND
                 DIRECTORS AND OFFICERS OF SURVIVING CORPORATION

Section 2.1    Certificate of Incorporation of the Surviving Corporation.......2
Section 2.2    Bylaws of the Surviving Corporation.............................2
Section 2.3    Directors of Surviving Corporation..............................3
Section 2.4    Officers of Surviving Corporation...............................3

                                    ARTICLE 3
                        EFFECT OF THE MERGER ON THE STOCK
                 OF INX AND MERGER SUB; EXCHANGE OF CERTIFICATES

Section 3.1    Effect on INX Stock and INX Stock Options.......................3
Section 3.2    Effect on the Stock of Merger Sub...............................4
Section 3.3    Exchange of Certificates........................................4
Section 3.4    Rule 16b-3 Approval.............................................5
Section 3.5    Dissenting Shares...............................................5

                                    ARTICLE 4
                      REPRESENTATIONS AND WARRANTIES OF INX

Section 4.1    Existence; Good Standing; Corporate Authority...................5
Section 4.2    Authorization, Validity and Effect of Agreements................6

                                    ARTICLE 5
                    REPRESENTATIONS AND WARRANTIES OF PARENT

Section 5.1    Existence; Good Standing; Corporate Authority...................6
Section 5.2    Authorization, Validity and Effect of Agreements................6
Section 5.3    Issuance of Parent Common Stock.................................6
Section 5.4    No Conflict.....................................................6
Section 5.5    Vote Required...................................................7
Section 5.6    Filings with the Securities and Exchange Commission.............7
Section 5.7    Merger Sub......................................................8
</TABLE>

                                       i
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<TABLE>
<S>                                                                         <C>
                                    ARTICLE 6
                  REPRESENTATIONS AND WARRANTIES OF MERGER SUB

Section 6.1    Existence.......................................................8
Section 6.2    Authorization, Validity and Effect of Agreements................8

                                    ARTICLE 7
               REPRESENTATIONS AND WARRANTIES OF THE STOCKHOLDERS

Section 7.1    Ownership of INX Common Stock...................................8
Section 7.2    Authority Relative to this Agreement............................9
Section 7.3    No Violations...................................................9
Section 7.4    Consents and Approvals.........................................10
Section 7.5    Investment in Parent...........................................10
Section 7.6    Access to Information..........................................10
Section 7.7    Restricted Securities..........................................10
Section 7.8    No Regulatory Recommendations..................................10
Section 7.9    Legal Counsel..................................................11

                                    ARTICLE 8
                            COVENANTS AND AGREEMENTS

Section 8.1    Proxy Statement................................................11
Section 8.2    Parent Meeting.................................................11
Section 8.3    INX Stockholders Written Consents..............................11
Section 8.4    INX Voting and Support Agreements..............................11
Section 8.5    Stockholder Representative.....................................11
Section 8.6    Delivery of INX Certificates to Stockholder Representative.....12
Section 8.7    Private Placement..............................................12
Section 8.8    Listing Application............................................12
Section 8.9    INX Employee Stock Options, Incentives and Benefit Plans.......13
Section 8.10   Restrictions on Parent Common Stock............................13

                                    ARTICLE 9
                                   CONDITIONS

Section 9.1    Conditions to Each Party's Obligation to Effect the Merger.....14
Section 9.2    Conditions to Obligation of INX to Effect the Merger...........15
Section 9.3    Conditions to Obligation of Parent to Effect the Merger........15

                                   ARTICLE 10
                                   TERMINATION

Section 10.1   Termination by Mutual Consent..................................16
Section 10.2   Termination by INX or Parent...................................16
Section 10.3   Termination by INX.............................................16
Section 10.4   Termination by Parent..........................................16
Section 10.5   Effect of Termination..........................................17
Section 10.6   Extension; Waiver..............................................17
</TABLE>

                                       ii
<PAGE>
<TABLE>
<S>                                                                         <C>
                                   ARTICLE 11
                               GENERAL PROVISIONS

Section 11.1   Nonsurvival of Representations, Warranties and Agreements......17
Section 11.2   Notices........................................................17
Section 11.3   Assignment; Binding Effect; Benefit............................18
Section 11.4   Entire Agreement...............................................18
Section 11.5   Expenses.......................................................18
Section 11.6   Amendments.....................................................18
Section 11.7   Governing Law..................................................19
Section 11.8   Counterparts...................................................19
Section 11.9   Headings.......................................................19
Section 11.10  Interpretation.................................................19
Section 11.11  Waivers........................................................19
Section 11.12  Incorporation of Exhibits......................................20
Section 11.13  Severability...................................................20
</TABLE>

LIST OF EXHIBITS

Exhibit 2.1    Form of Certificate of Incorporation of the Surviving Entity

                                      iii
<PAGE>
                       GLOSSARY OF DEFINED TERMS

<TABLE>
<CAPTION>
DEFINED TERMS                                                   WHERE DEFINED
-------------                                                   -------------
<S>                                                             <C>
Agreement.......................................................Preamble
AMEX............................................................Section 3.1(c)
Certificate of Merger...........................................Section 1.3
Closing.........................................................Section 1.2
Closing Date....................................................Section 1.2
Code............................................................Recitals
Conversion Ratio................................................Section 3.1(b)
DGCL............................................................Recitals
Dissenting Shares...............................................Section 3.5
Effective Time..................................................Section 1.3
Exchange Act....................................................Section 3.4
Fractional Cash Payment.........................................Section 3.1(c)
INX.............................................................Preamble
INX Certificates................................................Section 3.1(b)
INX Common Stock................................................Recitals
INX Stock Option................................................Section 7.1(b)
INX Stock Option Plans..........................................Section 7.1(b)
INX Stockholder Consent.........................................Section 7.1(a)
Lost Stock Affidavit............................................Section 3.3(b)
Material Adverse Effect.........................................Section 11.10(c)
Merger..........................................................Recitals
Merger Consideration............................................Section 3.1(c)
Merger Sub......................................................Recitals
Merger Sub Common Stock.........................................Section 3.2
New INX Common Stock............................................Section 3.2
Parent..........................................................Preamble
Parent Common Stock.............................................Section 3.1(b)
Parent Meeting..................................................Section 8.1
Parent Regulatory Filings.......................................Section 5.4(b)
Proxy Statement.................................................Section 8.1
Reg D PPM.......................................................Section 7.6
Rule 16b-3......................................................Section 3.4
SEC.............................................................Section 3.4
Securities Act..................................................Section 4.4(b)
Special Meeting Matters.........................................Section 5.5
Stock Consideration.............................................Section 3.1(b)
Stockholder.....................................................Preamble
Stockholder Representative......................................Section 8.5A
Surviving Corporation...........................................Section 1.1
Third-Party Provisions..........................................Section 11.3
</TABLE>

                                       iv
<PAGE>
                          PLAN AND AGREEMENT OF MERGER

      THIS PLAN AND AGREEMENT OF MERGER (this "AGREEMENT") is made and entered
into as of February 1, 2005, by and among I-Sector Corporation, a Delaware
corporation ("PARENT"), INX Merger Sub, Inc., a Delaware corporation and
wholly-owned subsidiary of Parent ("MERGER SUB"), Internetwork Experts, Inc., a
Delaware corporation and majority-owned subsidiary of Parent ("INX") and each of
the stockholders of INX other than Parent that are signatories hereto (each a
"STOCKHOLDER" and collectively the "STOCKHOLDERS").

                                    RECITALS

      WHEREAS, the Board of Directors of Parent has approved this Agreement and
determined that the merger of Merger Sub with and into INX (the "MERGER") in
accordance with the provisions of the Delaware General Corporation Law, as
amended (the "DGCL"), and subject to the terms and conditions of this Agreement,
is advisable and in the best interests of Parent and its stockholders;

      WHEREAS, the Board of Directors of Merger Sub has approved this Agreement
and determined that the Merger in accordance with the provisions of DGCL, and
subject to the terms and conditions of this Agreement, is advisable and in the
best interests of Merger Sub and its stockholders;

      WHEREAS, the director and sole stockholder of Merger Sub has approved this
Agreement;

      WHEREAS, the Board of Directors of INX has approved this Agreement and
determined that the Merger, in accordance with the provisions of the DGCL, and
subject to the terms and conditions of this Agreement, is advisable and in the
best interests of INX and its stockholders;

      WHEREAS, as a result of the Merger, and in accordance with the DGCL, each
issued and outstanding share of INX common stock, par value $0.001 per share
(the "INX COMMON STOCK"), other than shares of INX Common Stock owned by Parent,
Merger Sub, INX or any wholly-owned subsidiary of Parent immediately prior to
the Effective Time, shall, upon the terms and subject to the conditions set
forth herein, be converted into the right to receive the Merger Consideration;
and

      WHEREAS, the merger is intended to qualify as a reorganization under the
provisions of Section 368(a)(i)(B) of the Internal Revenue Code of 1986, as
amended (the "CODE").

      NOW, THEREFORE, in consideration of the foregoing, and of the
representations, warranties, covenants and agreements contained herein, the
parties hereto hereby agree as follows:

                                       1
<PAGE>
                                    ARTICLE 1
                                   THE MERGER

      Section 1.1 The Merger. At the Effective Time, upon the terms and subject
to the conditions of this Agreement, and in accordance with the DGCL, Merger Sub
shall be merged with and into INX, and the separate existence of Merger Sub
shall cease and INX shall continue as the surviving Corporation (sometimes
hereinafter referred to as the "SURVIVING CORPORATION").

      Section 1.2 The Closing. Upon the terms and subject to the conditions of
this Agreement, the closing of the Merger (the "CLOSING") shall take place at
(a) the offices of Porter & Hedges, L.L.P., 700 Louisiana, 35th Floor, Houston,
Texas 77002, at 10:00 a.m., local time, on the first business day after
satisfaction or waiver of the conditions set forth in SECTION 9.1, or, if on
such day any condition set forth in SECTION 9.2 or SECTION 9.3 has not been
satisfied or waived, as soon as practicable after all the conditions set forth
in ARTICLE 9 have been satisfied or waived in accordance herewith, or (b) at
such other time, date or place as INX and the Parent may agree in writing. The
date on which the Closing occurs is hereinafter referred to as the "CLOSING
DATE."

      Section 1.3 Effective Time. Prior to the Closing, the Parent, Merger Sub
and INX shall prepare, and on the Closing Date shall cause a certificate of
merger meeting the requirements of Section 251 of the DGCL with respect to the
Merger (the "CERTIFICATE OF MERGER") to be properly executed and filed in
accordance with such section. The Merger shall become effective at such time as
the Certificate of Merger is properly executed and filed, or at such other time
as Parent and INX shall have agreed upon and designated in the Certificate of
Merger as the effective time of the Merger (such time at which the Merger shall
have become effective is referred to herein as the "EFFECTIVE TIME").

      Section 1.4 Effects of the Merger. The Merger shall have the effects set
forth in Section 259 of the DGCL. Parent agrees that it will be responsible for,
and will pay, all applicable fees, charges and incorporation and franchise taxes
required by law to be paid by Merger Sub.

                                   ARTICLE 2
                          ORGANIZATIONAL DOCUMENTS AND
                 DIRECTORS AND OFFICERS OF SURVIVING CORPORATION

      Section 2.1 Certificate of Incorporation of the Surviving Corporation. As
of the Effective Time, the certificate of incorporation of the Merger Sub set
forth in Error! Reference source not found. hereto shall be the certificate of
incorporation of the Surviving Corporation until duly amended in accordance with
applicable law; provided, however, that at the Effective Time, the certificate
of incorporation of the Merger Sub shall be amended to provide that the name of
the Surviving Corporation from and after the Effective Time shall be
"Internetwork Experts, Inc."

      Section 2.2 Bylaws of the Surviving Corporation. As of the Effective Time,
the existing bylaws of INX shall be the bylaws of the Surviving Corporation
until duly amended in accordance with applicable law.

                                       2
<PAGE>
      Section 2.3 Directors of Surviving Corporation. The directors of INX shall
resign effective immediately prior to the Effective Time. The directors of
Merger Sub immediately prior to the Effective Time shall become directors of INX
and shall serve until their successors have been duly elected or appointed and
qualified or until their earlier death, resignation or removal in accordance
with the Surviving Corporation's certificate of incorporation and bylaws and the
DGCL.

      Section 2.4 Officers of Surviving Corporation. The officers of INX
immediately prior to the Effective Time shall continue to be the officers of the
Surviving Corporation until their successors are duly appointed.

                                   ARTICLE 3
                        EFFECT OF THE MERGER ON THE STOCK
                 OF INX AND MERGER SUB; EXCHANGE OF CERTIFICATES

      Section 3.1 Effect on INX Stock and INX Stock Options. As of the Effective
Time, by virtue of the Merger, and without any further action by Merger Sub or
INX or by the holders of any securities of Merger Sub or INX:

            (a) Cancellation of Treasury Stock and Parent Owned Stock. Each
      share of INX Common Stock that is owned by INX, Merger Sub, Parent or any
      wholly-owned subsidiary of INX or Parent immediately prior to the
      Effective Time shall automatically be canceled and retired and shall cease
      to exist, and no consideration shall be delivered in exchange therefor.

            (b) Conversion of INX Common Stock. Each issued and outstanding
      share of INX Common Stock (other than shares to be canceled in accordance
      with SECTION 3.1(A) or as otherwise provided for in SECTION 3.5 with
      respect to shares of INX Common Stock as to which appraisal rights have
      been exercised) shall be converted into the right to receive 0.136054 (the
      "CONVERSION RATIO") of a share of the Parent's common stock, par value
      $0.01 per share (the "PARENT COMMON STOCK"). The Parent Common Stock
      issued in the Merger is hereinafter referred to as the "STOCK
      CONSIDERATION." As of the Effective Time, all such shares of INX Common
      Stock converted into the right to receive the Stock Consideration shall no
      longer be outstanding and shall automatically be canceled and retired and
      shall cease to exist, and each holder of a certificate or certificates
      which immediately prior to the Effective Time represented outstanding
      shares of INX Common Stock (the "INX CERTIFICATES") shall cease to have
      any rights with respect thereto, except the right to receive the Stock
      Consideration (plus the Fractional Cash Payment pursuant to subsection (c)
      below) into which such shares have been converted.

            (c) No Fractional Shares. Notwithstanding any other provision of
      this Agreement, no fractional shares of Parent Common Stock shall be
      issued upon the surrender for exchange of INX Certificates, and no holder
      of INX Common Stock shall be entitled to receive a fractional share of
      Parent Common Stock. Notwithstanding any other provision of this
      Agreement, each holder of shares of INX Common Stock converted pursuant to
      the Merger who would otherwise have been entitled to receive a fraction of
      a share of Parent Common Stock (after taking into account all INX

                                       3
<PAGE>
      Certificates delivered by such holder) shall receive from INX (and not
      from Parent or Merger Sub), in lieu thereof, cash (without interest) in an
      amount equal to such fractional amount multiplied by the average of the
      last reported sales prices of Parent Common Stock, as reported on the
      American Stock Exchange ("AMEX"), on each of the ten trading days
      immediately preceding the date of the Effective Time (such cash payment is
      referred to herein as the "FRACTIONAL CASH PAYMENT" and together with the
      Stock Consideration, the "MERGER CONSIDERATION").

            (d) Assumption of INX Employee Stock Options. Each INX stock option
      shall be assumed by Parent as set forth in SECTION 8.9.

      Section 3.2 Effect on the Stock of Merger Sub. As of the Effective Time,
each share of the Merger Sub's common stock, par value $.10 per share (the
"MERGER SUB COMMON STOCK"), that was outstanding prior to the Effective Time
shall be converted into one fully paid and nonassessable share of common stock
of the Surviving Corporation, par value $.10 per share ("NEW INX COMMON Stock").
As of the Effective Time, all such shares of Merger Sub Common Stock shall no
longer be outstanding and shall automatically be canceled and retired and shall
cease to exist, and each holder of a certificate or certificates which
immediately prior to the Effective Time represented outstanding shares of Merger
Sub Common Stock shall cease to have any rights with respect thereto, except the
right to receive the number of shares of New INX Common Stock into which such
shares have been converted.

      Section 3.3 Exchange of Certificates.

            (a) Surrender of INX Certificates. At the Closing, each holder of
      record of shares of INX Common Stock whose shares were converted into the
      right to receive the Merger Consideration pursuant to SECTION 3.1 shall
      deliver, or cause to be delivered on its behalf, one or more INX
      Certificates, in proper and negotiable form representing the number of
      shares of INX Common Stock held of record by each such holder. Upon
      surrender of an INX Certificate for cancellation to Parent, together with
      such other documents as may reasonably be required by the Parent, the
      holder of such Certificate that is entitled to receive Parent Common Stock
      in the Merger shall receive in exchange therefor a certificate
      representing that number of whole shares of Parent Common Stock in the
      Merger shall receive in exchange therefor a certificate representing that
      number of whole shares of Parent Common Stock which such holder has the
      right to receive pursuant to the provisions of this ARTICLE 3 and cash in
      lieu of any fractional share of Parent Common Stock in accordance with
      SECTION 3.1(C) and the INX Certificate so surrendered shall forthwith be
      canceled. No interest shall be paid or will accrue on any cash payable to
      holders of Certificates pursuant to the provisions of this ARTICLE 3.

            (b) Lost Certificates. If any INX Certificate shall have been lost,
      stolen or destroyed, in lieu of such INX Certificate, the Stockholder
      claiming such INX Certificate to be lost, stolen or destroyed shall
      deliver an affidavit of that fact, in such form as may be requested by the
      Parent or the Parent's transfer agent (the "LOST STOCK AFFIDAVIT"). The
      Parent may require the posting by such Stockholder of a bond in such
      reasonable amount as the Parent may direct as indemnity against any claim
      that may be made against it with respect to such lost, stolen or destroyed
      INX Certificate.

                                       4
<PAGE>
            (c) No Further Ownership Rights in INX Common Stock. All shares of
      Parent Common Stock issued upon the surrender of an INX Certificate in
      accordance with the terms of this ARTICLE 3 (including any Fractional Cash
      Payments paid by INX pursuant to this ARTICLE 3) shall be deemed to have
      been issued (and paid) in full satisfaction of all rights pertaining to
      the shares of INX Common Stock theretofore represented by such INX
      Certificates, subject, however, to the Surviving Entity's obligation to
      pay any dividends or make any other distributions with a record date prior
      to the Effective Time which may have been authorized or made by INX on
      such shares of INX Common Stock as the case may be, which remain unpaid at
      the Effective Time.

      Section 3.4 Rule 16b-3 Approval. Each of the Parent, INX and Merger Sub
agree that their respective board of directors shall, at or prior to the
Effective Time, adopt resolutions specifically approving, for purposes of Rule
16b-3 ("RULE 16B-3") of the United States Securities and Exchange Commission
(the "SEC") under the Securities Exchange Act of 1934, as amended (the "EXCHANGE
ACT"), the receipt, pursuant to this Agreement, of Parent Common Stock and of
options to acquire Parent Common Stock, by executive officers or directors of
the Parent and INX who become executive officers or directors of the Parent
subject to Rule 16b-3.

      Section 3.5 Dissenting Shares. Notwithstanding SECTION 3.1, shares of INX
Common Stock outstanding immediately prior to the Effective Time and held by a
holder of record who has not consented to the Merger in writing and who has
demanded appraisal for such shares of INX Common Stock ("DISSENTING SHARES") in
accordance with the DGCL shall not be converted into a right to receive any
applicable Merger Consideration, unless such holder fails to perfect or
withdraws or otherwise loses his right to appraisal. If after the Effective Time
such holder of record fails to perfect or withdraws or loses his right to
appraisal, such shares of INX Common Stock shall be treated as if they had been
cancelled and converted as of the Effective Time into a right to receive the
applicable Merger Consideration. Any consideration other than the Merger
Consideration with respect to such Dissenting Shares shall be paid exclusively
by INX, and Parent shall have no obligation for same. INX shall give Parent
prompt notice of any demands received for appraisal of shares of INX Common
Stock, and Parent shall have the right to participate in all negotiations and
proceedings with respect to such demands. INX shall not, except with the prior
written consent of Parent, make any payment with respect to, or settle or offer
to settle, any such demands.

                                   ARTICLE 4
                      REPRESENTATIONS AND WARRANTIES OF INX

      INX hereby represents and warrants to the Parent as follows:

      Section 4.1 Existence; Good Standing; Corporate Authority. INX is a
corporation duly incorporated, validly existing and in good standing under the
laws of Delaware. INX is duly qualified to do business and, to the extent such
concept or similar concept exists in the relevant jurisdiction, is in good
standing under the laws of any jurisdiction in which the character of the
properties owned or leased by it therein or in which the transaction of its
business makes such qualification necessary, except where the failure to be so
qualified does not and is not reasonably likely to have, individually or in the
aggregate, a Material Adverse Effect (as defined

                                       5
<PAGE>
in SECTION 11.10(C)). INX has all requisite corporate power and authority to
own, operate and lease its properties and to carry on its business as now
conducted.

      Section 4.2 Authorization, Validity and Effect of Agreements. INX has the
requisite corporate power and authority to execute and deliver this Agreement
and all other agreements and documents contemplated hereby and thereby to which
it is a party. The consummation by INX of the transactions contemplated hereby
have been duly authorized by all requisite corporate action on behalf of INX.
This Agreement constitutes valid and legally binding obligation of INX,
enforceable against INX in accordance with its terms, subject to applicable
bankruptcy, insolvency, reorganization, moratorium or other similar laws
relating to creditors' rights and general principles of equity.

                                   ARTICLE 5
                    REPRESENTATIONS AND WARRANTIES OF PARENT

      Parent hereby represents and warrants to each Stockholder as follows:

      Section 5.1 Existence; Good Standing; Corporate Authority. Parent is a
corporation duly incorporated, validly existing and in good standing under the
laws of Delaware. Parent is duly qualified to do business and, to the extent
such concept or similar concept exists in the relevant jurisdiction, is in good
standing under the laws of any jurisdiction in which the character of the
properties owned or leased by it therein or in which the transaction of its
business makes such qualification necessary, except where the failure to be so
qualified does not and is not reasonably likely to have, individually or in the
aggregate, a Material Adverse Effect. Parent has all requisite corporate power
and authority to own, operate and lease its properties and to carry on its
business as now conducted.

      Section 5.2 Authorization, Validity and Effect of Agreements. Parent has
the requisite corporate power and authority to execute and deliver this
Agreement and all other agreements and documents contemplated hereby and thereby
to which it is a party. The consummation by Parent of the transactions
contemplated hereby have been duly authorized by all requisite corporate action
on behalf of Parent, other than the approvals referred to in SECTION 5.5. This
Agreement constitutes valid and legally binding obligation of Parent enforceable
against Parent, in accordance with its terms, subject to applicable bankruptcy,
insolvency, reorganization, moratorium or other similar laws relating to
creditors' rights and general principles of equity.

      Section 5.3 Issuance of Parent Common Stock. The shares of Parent Common
Stock to be issued as part of the Merger Consideration, when issued in
accordance with the terms of this Agreement, will be duly authorized, validly
issued, fully paid and nonassessable.

      Section 5.4 No Conflict.

            (a) Neither the execution and delivery by Parent of this Agreement
      nor the consummation by Parent of the transactions contemplated hereby or
      thereby in accordance with their terms will (i) conflict with or result in
      a breach of any provisions of the certificate of incorporation, as
      amended, or bylaws of Parent, (ii) violate, or conflict with, or result in
      a breach of any provision of, or constitute a default (or an event which,
      with notice or lapse of time or both, would constitute a default) under,
      or result in the

                                       6
<PAGE>
      termination or in a right of termination or cancellation of, or give rise
      to a right of purchase under, or accelerate the performance required by,
      or result in being declared void, voidable, or without further binding
      effect, or otherwise result in a detriment to Parent or any of its
      Subsidiaries under, any of the terms, conditions or provisions of, any
      note, bond, mortgage, indenture, deed of trust, license, franchise,
      permit, lease, contract, agreement, joint venture or other instrument or
      obligation to which Parent or any of its Subsidiaries is a party, or by
      which Parent or any of its Subsidiaries or any of their properties is
      bound or affected or (iii) subject to the filings and other matters
      referred to in SECTION 5.4(B), contravene or conflict with or constitute a
      violation of any provision of any law, rule, regulation, judgment, order
      or decree binding upon or applicable to Parent or any of its Subsidiaries,
      except, for such matters described in clause (ii) or (iii) as do not and
      are not reasonably likely to have, individually or in the aggregate, a
      Material Adverse Effect.

            (b) Neither the execution and delivery by Parent of this Agreement
      nor the consummation by Parent of the transactions contemplated hereby in
      accordance with its terms will require any consent, approval or
      authorization of, or filing or registration with, any governmental or
      regulatory authority, other than (i) compliance with the DGCL, with
      respect to the filing of the Certificate of Merger, (ii) compliance with
      the applicable rules of the AMEX, (iii) compliance with the "blue sky"
      laws of various states and applicable foreign competition and antitrust
      laws, and (iv) collectively, the "PARENT REGULATORY FILINGS"), except for
      any consent, approval or authorization the failure of which to obtain and
      for any filing or registration the failure of which to make does not and
      is not reasonably likely to have a Material Adverse Effect or
      substantially impair or delay the consummation of the transactions
      contemplated hereby.

      Section 5.5 Vote Required. The only votes of the holders of any class or
series of Parent capital stock necessary to approve (i) the issuance of the
shares of Parent Common Stock in the merger and the shares of Parent Common
Stock to be issued upon exercise of INX options assumed pursuant to the Merger
and (ii) the amendment to the I-Sector Corporation Incentive Plan (collectively,
the "SPECIAL MEETING MATTERS") are the affirmative vote of the holders of at
least a majority of the Parent Common Stock represented at the Parent Meeting,
at which a quorum is present, and cast on the Special Meeting Matters.

      Section 5.6 Filings with the Securities and Exchange Commission. Parent
has filed all reports required to be filed by it under the Exchange Act,
including pursuant to Section 13(a) or 15(d) thereof, for the twelve months
preceding the date hereof (the foregoing materials being collectively referred
to herein as the "PARENT SEC REPORTS") on a timely basis or has received a valid
extension of such time of filing and has filed any such Parent SEC Reports prior
to the expiration of any such extension. As of their respective dates, the
Parent SEC Reports complied in all material respects with the requirements of
the Exchange Act and the rules and regulations of the SEC promulgated
thereunder, and none of the Parent SEC Reports, when filed, contained any untrue
statement of a material fact or omitted to state a material fact required to be
stated therein or necessary in order to make the statements therein, in light of
the circumstances under which they were made, not misleading. The financial
statements of Parent included in the SEC Reports comply in all material respects
with applicable accounting requirements and the rules and regulations of the
Commission with respect thereto as in effect at the time of filing. Such

                                       7
<PAGE>
financial statements have been prepared in accordance with generally accepted
accounting principles applied on a consistent basis during the periods involved,
except as may be otherwise specified in such financial statements or the notes
thereto, and fairly present in all material respects the financial position of
Parent and its consolidated subsidiaries as of and for the dates thereof and the
results of operations and cash flows for the periods then ended, subject, in the
case of unaudited statements, to normal, year-end audit adjustments.

      Section 5.7 Merger Sub. Merger Sub has not conducted any business
activities prior to the date of this Agreement, other than the negotiation and
execution of this Agreement. All outstanding shares of capital stock of Merger
Sub are owned, beneficially and of record, by Parent.

                                   ARTICLE 6
                  REPRESENTATIONS AND WARRANTIES OF MERGER SUB

      Merger Sub hereby represents and warrants as follows:

      Section 6.1 Existence. The Merger Sub is a corporation duly organized,
validly existing and in good standing under the laws of the State of Delaware.

      Section 6.2 Authorization, Validity and Effect of Agreements. Merger Sub
has the requisite corporate power and authority to execute and deliver this
Agreement and all other agreements and documents contemplated hereby and thereby
to which it is a party. The consummation by Merger Sub of the transactions
contemplated hereby have been duly authorized by all requisite corporate action
on behalf of Merger Sub. This Agreement constitutes valid and legally binding
obligation of Merger Sub enforceable against Merger Sub, in accordance with its
terms, subject to applicable bankruptcy, insolvency, reorganization, moratorium
or other similar laws relating to creditors' rights and general principles of
equity.

                                   ARTICLE 7
               REPRESENTATIONS AND WARRANTIES OF THE STOCKHOLDERS

      Each Stockholder, severally but not jointly, represents and warrants to
Parent, Merger Sub and INX that:

      Section 7.1 Ownership of INX Common Stock.

            (a) Such Stockholder is the sole record holder of the shares of INX
      Common Stock set forth in that certain Consent of INX Stockholders to the
      Merger (the "INX STOCKHOLDER CONSENT") delivered to Parent and INX
      concurrently with the execution of this Agreement and has the sole legal
      and beneficial ownership of, and good and marketable title to, those
      shares of INX Common Stock. All of the shares of INX Common Stock owned by
      such Stockholder are free and clear of any Liens or other rights or
      interests of any person or entity and there is no security, option,
      warrant, right (including, without limitation, preemptive rights), put,
      call, subscription agreement, commitment, understanding or claim of any
      nature whatsoever, fixed or contingent, to which such Stockholder,
      individually, is a party or by which such Stockholder, individually, is
      bound that directly or indirectly (i) calls for the sale, pledge, delivery
      or

                                       8
<PAGE>
      other disposition of any interests in INX or any securities convertible
      into, or other rights to acquire, any interests in INX, (ii) relates to
      the voting or control of any interests in INX, or (iii) obligates such
      Stockholder to grant, offer or enter into any of the foregoing. Such
      Stockholder has the absolute and unrestricted legal right, power,
      authority and capacity to transfer his shares of INX Common Stock.

            (b) Such Stockholder has been granted options to purchase INX Common
      Stock (an "INX STOCK OPTION") under the INX Incentive Plan, as amended and
      restated effective August 1, 2003 (the "INX STOCK OPTION PLAN") set forth
      next to such Stockholder's name on the INX Stockholder Consent and has the
      sole beneficial ownership of those shares of INX Common Stock issuable
      under the INX Stock Options. All of the INX Stock Options set forth next
      to the Stockholder's name on the INX Stockholder Consent and shares of INX
      Common Stock issuable upon the exercise of the INX Stock Options, are free
      and clear of any Liens or other rights or interests of any person or
      entity and there is no security, option, warrant, right (including,
      without limitation, preemptive rights), put, call, subscription agreement,
      commitment, understanding or claim of any nature whatsoever, fixed or
      contingent, to which such Stockholder, individually, is a party or by
      which such Stockholder, individually, is bound that directly or indirectly
      (i) calls for the sale, pledge, delivery or other disposition of any
      interests in INX or any securities convertible into, or other rights to
      acquire, any interests in INX, (ii) relates to the voting or control of
      any interests in the INX, or (ii) obligates such Stockholder to grant,
      offer or enter into any of the foregoing.

            (c) Except as set forth in subsections (a) and (b), such Stockholder
      has no legal or beneficial ownership of, or right or claim to any INX
      Common Stock, INX Stock Option or other securities of INX or securities
      convertible into INX Common Stock.

      Section 7.2 Authority Relative to this Agreement. Such Stockholder has the
legal capacity to enter into and perform its obligations under this Agreement
and to consummate the transactions contemplated hereby. This Agreement has been
duly executed by such Stockholder. Assuming the valid execution and deliver of
this Agreement by all other parties to this Agreement, this Agreement is a valid
and binding obligation of such Stockholder, enforceable against such
Stockholder, in accordance with its terms, except as enforceability may be
limited by bankruptcy, insolvency, reorganization, moratorium or other Laws
relating to or affecting creditors' rights generally or by equitable principles.
Such Stockholder has executed and delivered the INX Stockholder Consent whereby
such Stockholder has consented to and approved this Agreement, the Merger and
the consummation of the transactions contemplated hereby and such Stockholder
has waived such Stockholder's rights of appraisal under the DGCL with respect to
the Merger and any rights, claims or other causes of action against Parent, INX
or Merger Sub.

      Section 7.3 No Violations. Neither the execution, delivery or performance
of this Agreement by the Stockholder, individually, will violate or conflict
with or result in a breach of, or constitute a default (or an event which, with
notice or lapse of time or both, would constitute a default) under or result in
the termination of, or accelerate the performance by, or result in a right of
termination under, or result in the creation of any Lien upon the shares of INX
Common Stock owned by such Stockholder or INX Stock Options or shares of INX
Common Stock underlying

                                       9
<PAGE>
INX Stock Options under, any contract, indenture, loan document, license,
permit, order, decree or instrument to which such Stockholder is a party or by
which it or its assets or properties are bound.

      Section 7.4 Consents and Approvals. No consent, order, approval, waiver,
authorization of, or registration, application, declaration or filing with, any
Person is required with respect to such Stockholder, individually, in connection
with the execution and delivery of this Agreement or the consummation of the
transaction contemplated thereby.

      Section 7.5 Investment in Parent. In approving the execution and delivery
of this Agreement and the consummation of the transactions contemplated hereby,
the Stockholder is making an investment decision to acquire shares of Parent
Common Stock. The Stockholder is acquiring the shares of Parent Common Stock for
its own account for investment, and not with a view to any distribution or
resale of such shares of Parent Common Stock in violation of the Securities Act
or any rule or regulation under the Securities Act and the Stockholder has no
present plans to enter into any contract, undertaking, agreement or arrangement
for any such distribution or resale.

      Section 7.6 Access to Information. The Stockholder hereby acknowledges
receipt of the Regulation D Private Placement Memorandum (the "REG D PPM")
containing information relating to Stockholder's investment in Parent Common
Stock. In addition to the information contained in the Reg D PPM, the
Stockholder (a) has had adequate opportunity to obtain from representatives of
the Parent such information about the Parent as is necessary to evaluate the
merits and risks of the acquisition of shares of Parent Common Stock pursuant to
this Agreement, (b) has sufficient expertise in business and financial matters
to be able to evaluate the risks involved in the acquisition of shares of Parent
Common Stock pursuant to this Agreement and to make an informed investment
decision with respect to such acquisition, (c) is personally familiar with the
business of INX and Parent, and (d) acknowledges that the shares of Parent
Common Stock cannot be sold, transferred or otherwise disposed other than as
allowed by the rules and regulations of the SEC.

      Section 7.7 Restricted Securities. Stockholder acknowledges and agrees
that shares of Parent Common Stock to be issued in the Merger are subject to
restrictions on transfer as set forth in SECTION 8.10 and further understands
that the shares of Parent Common Stock will not have been registered pursuant to
the Securities Act or any applicable state securities laws, that the shares of
Parent Common Stock will be characterized as "restricted securities" under
federal securities laws, and that under such laws and applicable regulations the
shares of Parent Common Stock cannot be sold or otherwise disposed of without
registration under the Securities Act or an exemption therefrom. In this
connection, such Investor represents that it is familiar with Rule 144
promulgated under the Securities Act, as currently in effect, and understands
the resale limitations imposed thereby and by the Securities Act. Appropriate
stop transfer instructions may be issued to the transfer agent for securities of
the Company (or a notation may be made in the appropriate records of the
Company) in connection with the shares of Parent Common Stock.

      Section 7.8 No Regulatory Recommendations. The Stockholder understands
that there has not been any finding or determination by any federal or state
regulatory authority relating to

                                       10
<PAGE>
the fairness of an investment in the shares of Parent Common Stock to be issued
to the Stockholder in the Merger, and there has not been any approval,
recommendation, or endorsement of either the offering of the shares or the
shares themselves by any federal or state regulatory authority.

      Section 7.9 Legal Counsel. SUCH STOCKHOLDER UNDERSTANDS THAT IT IS HIS,
HER OR ITS RESPONSIBILITY TO OBTAIN ITS OWN LEGAL AND FINANCIAL ADVISORS
(INCLUDING TAX ADVISORS) WITH RESPECT TO THIS AGREEMENT AND THE TRANSACTIONS
CONTEMPLATED HEREBY AND THAT PORTER & HEDGES, L.L.P. IS REPRESENTING ONLY PARENT
IN CONNECTION WITH THIS AGREEMENT, THE MERGER AND THE TRANSACTIONS CONTEMPLATED
HEREBY AND NOT SUCH STOCKHOLDER.

                                   ARTICLE 8
                            COVENANTS AND AGREEMENTS

      Section 8.1 Proxy Statement. As promptly as practicable after the
execution of this Agreement, (i) Parent shall prepare and file with the SEC a
proxy statement (together with any amendments thereof or supplements thereto,
the "PROXY STATEMENT") relating to the special meeting of the Parent
stockholders (the "PARENT MEETING") to be held to consider approval of the
Special Meeting Matters. Parent shall use its reasonable best efforts to cause
the Proxy Statement to be mailed to its stockholders as promptly as practicable.

      Section 8.2 Parent Meeting. Parent shall call and hold the Parent Meeting
as promptly as practicable for the purpose of obtaining the approval of the
Special Meeting Matters by the Parent stockholders. Parent shall use its
reasonable best efforts to solicit from its stockholders proxies in favor of the
Share Issuance, and shall take all other commercially reasonable action
necessary or advisable to secure the vote or consent of its stockholders.

      Section 8.3 INX Stockholders Written Consents. Subject to SECTION 5.4 and
SECTION 9.1, INX shall, as promptly as practicable after execution of this
Agreement, seek the execution and delivery of the INX Stockholder Consent by any
INX stockholder that did not execute and deliver a INX Stockholder Consent to
Parent before the execution of this Agreement.

      Section 8.4 INX Voting and Support Agreements. INX shall, as promptly as
practicable after execution of this Agreement, seek the execution and delivery
of the Voting and Support Agreement by any INX stockholder or grantee under any
INX Stock Option who did not execute and deliver a Voting and Support Agreement
to Parent before the execution of this Agreement.

      Section 8.5 Stockholder Representative.

            (a) Each Stockholder hereby constitutes and appoints Mark Hilz or
      his duly designated substitutes as his representative and true and lawful
      agent and attorney-in-fact (collectively, the "STOCKHOLDER
      REPRESENTATIVE"), authorizing the Stockholder Representative to perform
      any and all such acts as are required, authorized or contemplated by this
      Agreement, including, but not limited to, the following: (i) to surrender
      the INX Certificates and Lost Stock Affidavits deposited with the
      Stockholder

                                       11
<PAGE>
      Representative to the Parent at the Closing; (ii) to execute and deliver
      stock powers, certificates and any other additional documentation as the
      Parent or the Parent's transfer agent may request to effectuate the
      exchange of the INX Common Stock for the Stock Consideration pursuant to
      SECTION 3.1; (iii) to receive all notices and other documents given or to
      be given to the Stockholders pursuant to this Agreement; (iv) to receive
      and accept service of process in connection with any claim or other
      proceeding against the Stockholders arising under this Agreement; (v) to
      undertake, compromise, defend and settle any such suit or proceeding on
      behalf of the Stockholders as a group arising under this Agreement; (vi)
      to execute and deliver all agreements, certificates and documents required
      or deemed appropriate by the Stockholder Representative in connection with
      any of the transactions contemplated by this Agreement whether prior to,
      at or after the Closing, including any amendments to this Agreement; (vii)
      to act pursuant to the direction of a majority in interest of the
      Stockholders; and (viii) receive the Merger Consideration on behalf of the
      Stockholders and distribute such Merger Consideration to the respective
      Stockholders, all in accordance with this Agreement.

            (b) A decision, act, consent or instruction of the Stockholder
      Representative shall be final, binding and conclusive upon each of such
      Stockholder, and Parent may rely conclusively, absolutely and exclusively,
      without inquiry, upon any such decision, act, consent or instruction of
      every such Stockholder. Parent is hereby relieved from any liability to
      any Person for any acts done by them in accordance with such decision,
      act, consent or instruction of the Stockholder Representative.

      Section 8.6 Delivery of INX Certificates to Stockholder Representative. At
least ten days before the Closing, each Stockholder shall deliver to the
Stockholder Representative their respective INX Certificates, in proper and
negotiable form representing the number of shares of INX Common Stock held of
record by such Stockholder as set forth on the signature pages attached hereto,
or a Lost Stock Affidavit for their respective INX Certificates.

      Section 8.7 Private Placement. Parent and each Stockholder shall use their
respective reasonable efforts to cause the Merger to qualify as a private
placement of Parent Common Stock under Section 4(2) of the Securities Act and
Rule 506 of Regulation D promulgated thereunder.

      Section 8.8 Listing Application.

            (a) Parent shall promptly prepare and submit to the AMEX a listing
      application covering the Parent Common Stock to be issued in the Merger or
      upon the exercise of the INX Stock Options and shall use its commercially
      reasonable best efforts to obtain, prior to the Effective Time, approval
      for the listing on the AMEX of such Parent Common Stock, subject to
      official notice of issuance.

            (b) The listing fees payable to the AMEX with respect to the listing
      applications or any amendments thereto shall be paid by Parent.

                                       12
<PAGE>

         Section 8.9 INX Employee Stock Options, Incentives and Benefit Plans.

                  (a) At the Effective Time, each INX Stock Option granted under
         the INX Stock Option Plan, whether vested or unvested, shall be deemed
         assumed by Parent and shall thereafter be deemed to constitute a
         fully-vested option (i) to acquire that number of shares of Parent
         Common Stock equal to the product of (x) number of shares of INX Common
         Stock that were granted under such INX Stock Option multiplied by (y)
         the Conversion Ratio, (ii) at an exercise price equal to the quotient
         of (a) the exercise price of such INX Stock Option as stated in the INX
         Stock Option divided by (b) the Conversion Ratio, and (iii) on the same
         terms and conditions as were applicable under such INX Stock Option
         immediately prior to the Effective Time (in accordance with the past
         practice of INX with respect to interpretation and application of such
         terms and conditions and in compliance with the requirements of Code
         Section 424). For example, and solely for the purposes of illustrating
         the mechanics of the conversion and assumption of an INX Stock Option,
         immediately prior to the Effective Time, an INX Stock Option to acquire
         735 shares of INX Common Stock at an exercise price of $0.20 per share
         shall be deemed to be an option to purchase 100 shares of Parent Common
         Stock (735 shares of INX Common Stock multiplied by the Conversion
         Ratio = 100 shares of Parent Common Stock) at an exercise price of
         $1.47 ($0.20 exercise price stated in INX Stock Option divided by the
         Conversion Ratio). In addition, each of Parent and INX shall prior to
         the Effective Time make any amendments to the terms of its respective
         stock option or compensation plans or arrangements that are necessary
         to give effect to the transactions contemplated by this Section.

                  (b) Parent shall take all corporate action necessary to
         reserve for issuance a sufficient number of shares of Parent Common
         Stock for delivery pursuant to this Section.

                  (c) As promptly as practicable after the Effective Time,
         Parent shall prepare and file with the SEC a registration statement on
         Form S-8 to register the shares of Parent Common Stock issuable upon
         the exercise of the INX Stock Options assumed by Parent pursuant to
         this Section.

         Section 8.10 Restrictions on Parent Common Stock.

                  (a) Each Stockholder covenants that in no event will it sell,
         transfer or otherwise dispose of any of the shares of Parent Common
         Stock it receives in the Merger other than in conjunction with an
         effective registration statement for the shares under the Securities
         Act or pursuant to an exemption therefrom, or in compliance with Rule
         144 promulgated under the Securities Act or to a person related to or
         an entity affiliated with said Purchaser and other than in compliance
         with the applicable securities regulation laws of any state;

                  (b) Parent will place a legend on each certificate
         representing shares of Parent Common Stock to be issued in the Merger
         substantially as follows:


                                       13
<PAGE>
                  THE SECURITIES REPRESENTED BY THIS INSTRUMENT OR DOCUMENT HAVE
                  BEEN ACQUIRED FOR INVESTMENT AND HAVE NOT BEEN REGISTERED
                  UNDER THE SECURITIES ACT OF 1933, AS AMENDED, OR THE
                  SECURITIES LAW OF ANY STATE OR FOREIGN JURISDICTION. WITHOUT
                  SUCH REGISTRATION, SUCH SECURITIES MAY NOT BE SOLD, PLEDGED,
                  HYPOTHECATED OR OTHERWISE TRANSFERRED EXCEPT UPON DELIVERY TO
                  THE COMPANY OF AN OPINION OF COUNSEL SATISFACTORY TO THE
                  COMPANY THAT REGISTRATION IS NOT REQUIRED FOR SUCH TRANSFER OR
                  THE SUBMISSION TO THE COMPANY OF SUCH OTHER EVIDENCE AS MAY BE
                  SATISFACTORY TO THE COMPANY TO THE EFFECT THAT ANY SUCH
                  TRANSFER SHALL NOT BE IN VIOLATION OF THE SECURITIES ACT OF
                  1933, AS AMENDED, THE SECURITIES LAW OF ANY STATE OR FOREIGN
                  JURISDICTION, OR ANY RULE OR REGULATION PROMULGATED
                  THEREUNDER.

                  (c) The legend set forth above shall be removed and Parent
         shall issue a certificate without such legend to the holder of the
         shares of Parent Common Stock upon which it is stamped, if, unless
         otherwise required by state securities laws, (i) such shares of Parent
         Common Stock are registered for resale under the Securities Act, (ii)
         in connection with a sale transaction, such holder provides the Parent
         with an opinion from counsel satisfactory to Parent in its sole
         discretion, to the effect that a public sale, assignment or transfer of
         the shares of Parent Common Stock may be made without registration
         under the Securities Act, or (iii) such holder provides Parent with an
         opinion of counsel satisfactory to Parent in its sole discretion that
         the shares of Parent Common Stock can be sold pursuant to Rule 144
         without any restriction as to the number of securities acquired as of a
         particular date that can then be immediately sold.

                  (d) Stop transfer instructions to the transfer agent of the
         shares of Parent Common Stock to be issued to the Stockholder in the
         Merger have been or will be placed with respect to the shares of Parent
         Common Stock to be issued to the Stockholder in the Merger so as to
         restrict the resale, pledge, hypothecation or other transfer thereof,
         subject to the further items hereof, including the provisions of the
         legend set forth in subparagraph (b) above.

                                    ARTICLE 9
                                   CONDITIONS

         Section 9.1 Conditions to Each Party's Obligation to Effect the Merger.
The respective obligation of each party to effect the Merger shall be subject to
the fulfillment at or prior to the Closing Date of the following conditions:

                  (a) The Special Meeting Matters shall have been adopted and
         approved by the requisite vote of the stockholders of Parent in
         accordance with the DGCL and rules and regulations of the SEC and AMEX;



                                       14
<PAGE>
                  (b) This Agreement and the transactions contemplated hereby
         shall have been adopted and approved by the stockholders of INX in
         accordance with the DGCL as well as the Company's certificate of
         incorporation and bylaws;

                  (c) No statute, rule, regulation executive order, decree,
         ruling or cease and desist order shall have enacted, entered
         promulgated or enforced by any U.S. federal or state or foreign
         governmental authority which prohibits the consummation of the Merger
         substantially on the terms contemplated hereby;

                  (d) None of the parties hereto shall be subject to any decree,
         order or injunction of a United States federal or state or foreign
         court of competent jurisdiction which prohibits the consummation of the
         Merger; and

                  (e) Parent shall have applied to list the Parent Common Stock
         to be issued in connection with the Merger on the AMEX.

         Section 9.2 Conditions to Obligation of INX to Effect the Merger. The
obligation of INX to effect the Merger shall be subject to the fulfillment at or
prior to the Closing Date of the following conditions:

                  (a) The representations and warranties of Parent contained in
         this Agreement (i) that are qualified as to materiality or Material
         Adverse Effect shall be true and correct in all respects as of the
         Closing Date, except to the extent such representations and warranties
         expressly relate to an earlier date (in which case as of such earlier
         date), and (ii) those not so qualified shall be true and correct in all
         respects as of the Closing Date, except to the extent such
         representations and warranties expressly relate to an earlier date (in
         which case as of such earlier date), except for such breaches of
         representations and inaccuracies in warranties in this clause (ii) that
         do not and are not reasonably likely to have, individually or in the
         aggregate, a Material Adverse Effect, and INX shall have received a
         certificate of Parent executed on its behalf by its President or one of
         its Vice Presidents, dated the Closing Date, certifying to such effect.

         Section 9.3 Conditions to Obligation of Parent to Effect the Merger.
The obligations of Parent to effect the Merger shall be subject to the
fulfillment at or prior to the Closing Date of the following conditions:

                  (a) The representations and warranties of each Stockholder
         contained in this Agreement shall be true and correct in all respects
         as of the Closing Date, except to the extent such representations and
         warranties expressly relate to an earlier date (in which case as of
         such earlier date);

                  (b) At any time after the date of this Agreement, there shall
         not have been any event or occurrence, or series of events or
         occurrences, that has had or is reasonably likely to have, individually
         or in the aggregate with all other events or occurrences since the date
         of this Agreement, a Material Adverse Effect;

                  (c) Each holder of INX Common Stock shall have executed and
         delivered to INX an INX Stockholder Consent;



                                       15
<PAGE>
                  (d) Each holder of an INX Stock Option shall have executed and
         delivered to the Parent a Voting and Support Agreement; and

                  (e) No holders of INX Common Stock shall have perfected their
         appraisal or dissenters' rights under the DGCL.

                                   ARTICLE 10
                                   TERMINATION

         Section 10.1 Termination by Mutual Consent. This Agreement may be
terminated at any time prior to the Effective Time by the mutual written consent
of Parent and INX whether before or after the vote of their respective
stockholders approving this Agreement.

         Section 10.2  Termination by INX or Parent. This Agreement may be
terminated at any time prior to the Effective Time by action of the board of
directors of INX or of Parent if:

                  (a) a meeting (including adjournments and postponements) of
         the stockholders of Parent for the purpose of obtaining the approval
         required by SECTION 9.1(A) shall have been held and such stockholder
         approval shall not have been obtained; or

                  (b) a U.S. federal, state or non-U.S. court of competent
         jurisdiction or U.S. federal, state or non-U.S. governmental,
         regulatory or administrative agency or commission shall have issued an
         order, decree or ruling or taken any other action permanently
         restraining, enjoining or otherwise prohibiting the transactions
         contemplated by this Agreement and such order, decree, ruling or other
         action shall have become final and nonappealable; provided, however,
         that the party seeking to terminate this Agreement pursuant to this
         clause (d) shall have complied with SECTION 8.3 and, with respect to
         other matters not covered by SECTION 8.3, shall have used its
         commercially reasonable best efforts to remove such injunction, order
         or decree.

         Section 10.3 Termination by INX. This Agreement may be terminated at
any time prior to the Effective Time by action of the board of directors of INX
if there has been a breach by Parent of any representation, warranty, covenant
or agreement set forth in this Agreement or if any representation or warranty of
Parent shall have become untrue, in either case such that the conditions set
forth in SECTION 9.2(A) would not be satisfied, and any such breach is not
curable, or, if curable, is not cured within 30 days after written notice of
such breach is given to Parent by INX; provided, however, that the right to
terminate this Agreement pursuant to SECTION 10.30 shall not be available to INX
if it, at such time, is in breach of any representation, warranty, covenant or
agreement set forth in this Agreement such that the condition set forth in
SECTION 9.3(A) shall not be satisfied.

         Section 10.4 Termination by Parent. This Agreement may be terminated at
any time prior to the Effective Time by action of the board of directors of
Parent if there has been a breach by INX or any Stockholder of any
representation, warranty, covenant or agreement set forth in this Agreement or
if any representation or warranty of INX shall have become untrue, in either
case such that the conditions set forth in SECTION 9.3(A) would not be
satisfied, and such breach is not curable, or, if curable, is not cured within
30 days after written notice of such breach is given



                                       16
<PAGE>
by Parent to INX; provided, however, that the right to terminate this Agreement
pursuant to this SECTION 10.4 shall not be available to Parent if it, at such
time, is in breach of any representation, warranty, covenant or agreement set
forth in this Agreement such that the conditions set forth in SECTION 9.2(A)
shall not be satisfied; or

         Section 10.5 Effect of Termination. If this Agreement is terminated
pursuant to this ARTICLE 9, all rights and obligations of the Parent, INX,
Merger Sub and the Stockholders hereunder shall terminate without any liability
of any party to any other party (except for any liability of any party then in
breach).

         Section 10.6 Extension; Waiver. At any time prior to the Effective
Time, each party may, to the extent legally allowed, (a) extend the time for the
performance of any of the obligations or other acts of the other parties hereto,
(b) waive any inaccuracies in the representations and warranties made to such
party contained herein or in any document delivered pursuant hereto and (c)
waive compliance with any of the agreements or conditions for the benefit of
such party contained herein. Any agreement on the part of a party hereto to any
such extension or waiver shall be valid only if set forth in an instrument in
writing signed on behalf of such party.

                                   ARTICLE 11
                               GENERAL PROVISIONS

         Section 11.1 Nonsurvival of Representations, Warranties and Agreements.
None of the representations, warranties and agreements in this Agreement or in
any instrument delivered pursuant to this Agreement shall survive the Merger.

         Section 11.2 Notices. Except as otherwise provided herein, any notice
required to be given hereunder shall be sufficient if in writing, and sent by
facsimile transmission or by courier service (with proof of service), hand
delivery or certified or registered mail (return receipt requested and
first-class postage prepaid), addressed as follows:

                  (a)      if to INX:

                                    Internetwork Experts, Inc.
                                    1955 Lakeway Drive
                                    Suite 220
                                    Lewisville, Texas  75057
                                    Attention:  Mark T. Hilz
                                    Facsimile:  (469) 549-3888

                  (b)      if to Parent or Merger Sub:

                                    I-Sector Corporation
                                    6401 Southwest Freeway
                                    Houston, Texas  77074
                                    Attention:  James H. Long
                                    Facsimile:  (713) 795-2001



                                       17
<PAGE>
                                    with a copy to:

                                    Porter & Hedges, L.L.P.
                                    700 Louisiana, Suite 3500
                                    Houston, Texas 77002
                                    Attention:  Nick D. Nicholas
                                    Facsimile:  (713) 226-0237

                  (c)      if to Stockholder Representative:

                                    Mark T. Hilz
                                    1955 Lakeway Drive
                                    Suite 220
                                    Lewisville, Texas  75057
                                    Facsimile:  (469) 549-3888

or to such other address as any party shall specify by written notice so given,
and such notice shall be deemed to have been delivered as of the date so
telecommunicated, personally delivered or mailed.

         Section 11.3 Assignment; Binding Effect; Benefit. Neither this
Agreement nor any of the rights, interests or obligations hereunder shall be
assigned by any of the parties hereto (whether by operation of law or otherwise)
without the prior written consent of the other parties. Subject to the preceding
sentence, this Agreement shall be binding upon and shall inure to the benefit of
the parties hereto and their respective successors and assigns. Notwithstanding
anything contained in this Agreement to the contrary, except for the provisions
of ARTICLE 3 and SECTION 8.8 and except as provided in any agreements delivered
pursuant hereto (collectively, the "THIRD-PARTY PROVISIONS"), nothing in this
Agreement, expressed or implied, is intended to confer on any person other than
the parties hereto or their respective heirs, successors, executors,
administrators and assigns any rights, remedies, obligations or liabilities
under or by reason of this Agreement. The Third-Party Provisions may be enforced
by the beneficiaries thereof.

         Section 11.4 Entire Agreement. This Agreement, the exhibits to this
Agreement and any documents delivered by the parties in connection herewith
constitute the entire agreement among the parties with respect to the subject
matter hereof and supersede all prior agreements and understandings among the
parties with respect thereto. No addition to or modification of any provision of
this Agreement shall be binding upon any party hereto unless made in writing and
signed by all parties hereto.

         Section 11.5 Expenses. Each party shall keep his own expenses, except
that Parent shall bear all expenses of the Merger Sub and all valid
reorganization expenses as permitted by IRS Revenue Ruling 73-54.

         Section 11.6 Amendments. This Agreement may be amended by the parties
hereto, by action taken or authorized by their boards of directors, at any time
before or after approval of matters presented in connection with the Merger by
the stockholders of INX or Parent but after any such stockholder approval, no
amendment shall be made which by law requires the further approval of
stockholders without obtaining such further



                                       18
<PAGE>
approval. This Agreement may not be amended except by an instrument in writing
signed on behalf of each of the parties hereto.

         Section 11.7 Governing Law. This Agreement shall be governed by and
construed in accordance with the laws of the State of Texas without regard to
its rules of conflict of laws.

         Section 11.8 Counterparts. This Agreement may be executed by the
parties hereto in separate counterparts, each of which when so executed and
delivered shall be an original, but all such counterparts shall together
constitute one and the same instrument. Each counterpart may consist of a number
of copies hereof each signed by less than all, but together signed by all of the
parties hereto.

         Section 11.9  Headings. Headings of the Articles and Sections of
this Agreement are for the convenience of the parties only and shall be given no
substantive or interpretative effect whatsoever.

         Section 11.10  Interpretation.  In this Agreement:

                  (a) Unless the context otherwise requires, words describing
         the singular number shall include the plural and vice versa, words
         denoting any gender shall include all genders, and words denoting
         natural persons shall include corporations and partnerships and vice
         versa.

                  (b) The phrase "to the knowledge of" and similar phrases
         relating to knowledge of INX or Parent, as the case may be, shall mean
         the actual knowledge of its executive officers and directors.

                  (c) "Material Adverse Effect" shall mean a material adverse
         effect on or change in (a) the business, assets, condition (financial
         or otherwise) or operations of a party (including the Surviving Entity)
         and its Subsidiaries on a consolidated basis, except for such changes
         or effects in general economic, capital market, regulatory or political
         conditions or changes that affect generally the IP telephony industry
         or changes arising out of the announcement of this Agreement, or (b)
         the ability of the party to consummate the transactions contemplated by
         this Agreement or fulfill the conditions to closing.

                  (d) The term "Subsidiary," when used with respect to any
         party, means any corporation or other organization (including a limited
         liability company), whether incorporated or unincorporated, domestic or
         foreign, of which such party directly or indirectly owns or controls
         (i) at least a majority of the securities or other interests having by
         their terms ordinary voting power to elect a majority of the board of
         directors or others performing similar functions with respect to such
         corporation or other organization or any organization of which such
         party is a general partner or (ii) any form of equity interest or an
         interest of any other character that is convertible into an equity
         interest in such corporation or organization and such party has working
         control over the management of such corporation or organization.

         Section 11.11 Waivers. Except as provided in this Agreement, no action
taken pursuant to this Agreement, including, without limitation, any
investigation by or on behalf of any party,



                                       19
<PAGE>
shall be deemed to constitute a waiver by the party taking such action of
compliance with any representations, warranties, covenants or agreements
contained in this Agreement. The waiver by any party hereto of a breach of any
provision hereunder shall not operate or be construed as a waiver of any prior
or subsequent breach of the same or any other provision hereunder.

         Section 11.12 Incorporation of Exhibits. All exhibits attached hereto
and referred to herein are hereby incorporated herein and made a part hereof for
all purposes as if fully set forth herein.

         Section 11.13 Severability. Any term or provision of this Agreement
which is invalid or unenforceable in any jurisdiction shall, as to that
jurisdiction, be ineffective to the extent of such invalidity or
unenforceability without rendering invalid or unenforceable the remaining terms
and provisions of this Agreement or affecting the validity or enforceability of
any of the terms or provisions of this Agreement in any other jurisdiction. If
any provision of this Agreement is so broad as to be unenforceable, the
provision shall be interpreted to be only so broad as is enforceable.

                            [SIGNATURE PAGE FOLLOWS]
<PAGE>
         IN WITNESS WHEREOF, Parent, Merger Sub, INX, the Stockholders and the
Stockholder Representative have caused this Agreement to be executed as of the
date first above written.

INTERNETWORK EXPERTS, INC.                       I-SECTOR CORPORATION

By: /s/ Mark T. Hilz                               By: /s/ James H. Long
    ----------------------------------------           -------------------------
      Mark T. Hilz                                       James H. Long
      President and Chief Executive Officer              Chief Executive Officer


STOCKHOLDER REPRESENTATIVE                        INX MERGER SUB

  /s/ Mark T. Hilz                                By: /s/ James H. Long
--------------------------------------------          --------------------------
      Mark T. Hilz                                Name:   James H. Long
                                                       -------------------------
                                                         President
<PAGE>
                           COUNTERPART SIGNATURE PAGE
                                       TO
                           PLAN AND AGREEMENT OF MERGER
                                      AMONG
                   I-SECTOR CORPORATION, INX MERGER SUB, INC.
                         AND INTERNETWORK EXPERTS, INC.
                          DATED AS OF FEBRUARY 1, 2005

         IN WITNESS WHEREOF, Parent, Merger Sub, INX, the Stockholders and the
Stockholder Representative have caused this Agreement as of the date first above
written.

                                  STOCKHOLDERS

<TABLE>
<S>                                           <C>                                  <C>
      /s/ David Peoples                                   585,000                            456,300
      ------------------------------------    ----------------------------------   ---------------------------
      David Peoples                           Number of Shares of INX Common       Number of INX Stock Options
                                              Stock

      /s/ Don Smith                                       495,000                            754,100
      ------------------------------------    ----------------------------------   ---------------------------
      Don Smith                               Number of Shares of INX Common       Number of INX Stock Options
                                              Stock

      /s/ David DeYoung                                   330,930                            633,125
      ------------------------------------    ----------------------------------   ---------------------------
      David DeYoung                           Number of Shares of INX Common       Number of INX Stock Options
                                              Stock

      /s/ John C'de Baca                                  180,000                            140,400
      ------------------------------------    ----------------------------------   ---------------------------
      John C'de Baca                          Number of Shares of INX Common       Number of INX Stock Options
                                              Stock

      /s/ Andrew Cantrell                                  80,020                             63,507
      ------------------------------------    ----------------------------------   ---------------------------
      Andrew Cantrell                         Number of Shares of INX Common       Number of INX Stock Options
                                              Stock
</TABLE>
<PAGE>
<TABLE>
<S>                                           <C>                                  <C>
      /s/ Joey Johnson                                     50,400                             54,312
      ------------------------------------    ----------------------------------   ---------------------------
      Joey Johnson                            Number of Shares of INX Common       Number of INX Stock Options
                                              Stock

      /s/ Joel Hutton                                      45,000                             55,100
      ------------------------------------    ----------------------------------   ---------------------------
      Joel Hutton                             Number of Shares of INX Common       Number of INX Stock Options
                                              Stock

      /s/ Dave Plank                                        6,750                              6,680
      ------------------------------------    ----------------------------------   ---------------------------
      Dave Plank                              Number of Shares of INX Common       Number of INX Stock Options
                                              Stock

      /s/ Veronica Marriott                                 4,500                             11,010
      ------------------------------------    ----------------------------------   ---------------------------
      Veronica Marriott                       Number of Shares of INX Common       Number of INX Stock Options
                                              Stock

      /s/ Brian Cochran                                     3,600                              1,250
      ------------------------------------    ----------------------------------   ---------------------------
      Brian Cochran                           Number of Shares of INX Common       Number of INX Stock Options
                                              Stock

      /s/ Leigh McGregor                                    1,800                              6,404
      ------------------------------------    ----------------------------------   ---------------------------
      Leigh McGregor                          Number of Shares of INX Common       Number of INX Stock Options
                                              Stock

      /s/ Albert Lowry                                      1,800                               -0-
      ------------------------------------    ----------------------------------   ---------------------------
      Albert Lowry                            Number of Shares of INX Common       Number of INX Stock Options
                                              Stock
</TABLE>
<PAGE>
<TABLE>
<S>                                           <C>                                  <C>
      /s/ John Newell                                       3,700                              6,950
      ------------------------------------    ----------------------------------   ---------------------------
      John Newell                             Number of Shares of INX Common       Number of INX Stock Options
                                              Stock

      /s/ Gordon Jackson                                    9,000                               -0-
      ------------------------------------    ----------------------------------   ---------------------------
      Gordon Jackson                          Number of Shares of INX Common       Number of INX Stock Options
                                              Stock

      /s/ Casey Brydson                                     2,500                              5,000
      ------------------------------------    ----------------------------------   ---------------------------
      Casey Brydson                           Number of Shares of INX Common       Number of INX Stock Options
                                              Stock
</TABLE>