Exhibit 4.6

Core Plan

INFOVISTA S.A.        2004 STOCK OPTION PLAN        UNOFFICIAL TRANSLATION INTO ENGLISH FOR CONVENIENCE PURPOSES

On
the basis of the authorisation given by the extraordinary shareholders' meeting of December 15, 2003 to grant, on one or several occasions, options giving right by exercise to acquire
existing shares of InfoVista S.A. (hereinafter the "Company") to employees or executive officers of the Company and its Affiliated Companies, (so long as such employees or executive officers hold less
than 10% of the capital), in a maximum amount of 480,000 existing shares, the nominal value of which is 0.54 Euro each, the board of directors of the Company decided on August 17, 2004, under
the provisions of Article L. 225-177et seq. of the French Commercial Code, to adopt this set of rules (the "Plan") fixing the terms
and conditions applicable to the options bearing on shares of stock of the Company that will be granted to "Eligible Persons" (as such term is defined in each Local Plan).

1.PURPOSE OF THE PLAN



2.TERRITORIAL APPLICATION OF THE PLAN



Where
there is an inconsistency between provisions of the Core Plan and Local Plan, the provision of the Local Plan shall prevail.

3.DEFINITIONS

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4.STOCK SUBJECT TO THE PLAN



5.ADMINISTRATION OF THE CORE PLAN

5.1   Administration



5.2   Powers of the Board of Directors



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5.3   Effect of the Board's Decision



6.LIMITATIONS

7.DURATION OF THE PLAN



8.DURATION OF OPTIONS



9.PRICE OF EXERCISE OF OPTIONS

9.1   Share purchase price





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9.2   Payment of the purchase price of the Shares



9.3   Exercise of the Options and Tax & other liabilities



9.4   Indemnity



10.EXERCISE OF OPTIONS

10.1 Exercise procedure; Rights of Participants who become shareholders



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10.2 Exercise dates



10.3 Loss of the Continuing Status as an Eligible Person. Termination of an Eligible Person's employment contract or office



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10.4 Disability of a Participant



10.5 Death of a Participant



10.6 Suspension of the right to exercise options



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11.NON-TRANSFERABILITY OF OPTIONS



12.PROTECTION OF THE PARTICIPANTS' RIGHTS

12.1 Financial operations carried out by the Company



12.2 Merger, Dissolution or Liquidation of the Company



12.3 Change of Control of the Company



13.GRANT DATE

Notice of Grant shall be provided to each Participant within a reasonable time limit after the Grant Date.

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14.AMENDMENT AND TERMINATION OF THE PLAN



15.CONDITIONS APPLICABLE UPON EXERCISE OF OPTIONS

15.1 Mandatory Legal Provisions Compliance



15.2 Investment Representations



16.INFORMATION OF THE PARTICIPANTS



17.LAWJURISDICTIONLANGUAGE



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INFOVISTA S.A. 2004        FRENCH LOCAL STOCK OPTION PLAN        Schedule 1 to the InfoVista S.A. 2004 Stock Option Plan

Definitions and interpretation



Applicability of the Core Plan



Nominative Form

Shares

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Amendment and Termination of the French Local Plan

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INFOVISTA S.A. 2004        U.S. STOCK OPTION PLAN        Schedule 2 to the InfoVista S.A. 2004 Stock Option Plan

1.     Definitions

2.     Applicability of the Core Plan



3.     Eligibility



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4.     Options

5.     Capital Adjustments



6.     Withholding



7.     Amendment and Termination of the U.S. Plan

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INFOVISTA S.A. 2004        INTERNATIONAL STOCK OPTION PLAN        Schedule 3 to the InfoVista S.A. 2004 Employee Stock Option Plan

1.     Definitions and Interpretation



2.     APPLICABILITY OF THE CORE PLAN



3.     AMENDMENT AND TERMINATION OF THE INTERNATIONAL PLAN

4.     LAW AND JURISDICTION AND LANGUAGE



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