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                                                                    EXHIBIT 4.15



                      NON-QUALIFIED STOCK OPTION AGREEMENT

         This Non-Qualified Stock Option Agreement is made as of this ___ day of
______, 2000 (which date is hereinafter referred to as the "Date of Grant") by
and among MICROTEST, INC., a Delaware corporation (hereinafter referred to as
the "Company") and _________ (hereinafter referred to as "Participant"). If
Participant is presently or subsequently becomes employed by a subsidiary of the
Company, the term "Company" shall be deemed to refer collectively to Microtest,
Inc. and the subsidiary or subsidiaries which employ or engage the Participant.

                                    RECITALS

         A. From time to time, the Company grants stock options to key
employees, directors and officers of the Company as an incentive to encourage
these Participants to remain in its employment, or service and to enhance the
ability of the Company to attract individuals whose services are considered
unusually valuable by providing an opportunity to have a proprietary interest in
the success of the Company; and

         B. The Compensation Committee (the "Committee") of the Company's Board
of Directors believes that the granting of the Option herein described to
Participant is consistent with the stated purposes for the grant of a stock
option;

         NOW, THEREFORE, in consideration of the mutual covenants and conditions
hereinafter set forth and for other good and valuable consideration, the receipt
and sufficiency of which are hereby acknowledged, the Company and Participant
agree as follows:

         1. Grant of Option. The Company hereby grants to Participant the right
and option (hereinafter referred to as the "Option") to purchase an aggregate of
_______ shares (such number being subject to adjustment as provided in paragraph
number 12 hereof) of Microtest Common Stock (the "Stock") on the terms and
conditions herein set forth. This Option may be exercised in whole or in part
and from time to time only to the extent the Option is vested and as hereinafter
provided.

         2. Vesting. The Option shall be vested upon grant.

         3. Purchase Price. The price at which Participant shall be entitled to
purchase the Stock covered by the Option shall be $_______ per share (the Fair
Market Value on the Date of Grant).

         4. Term of Option. The Option hereby granted shall be and remain in
force and effect for a period of ten (10) years from the Date of Grant, through
and including the normal close of business of the Company on ____________
(hereinafter referred to as the "Expiration Date"), subject to earlier
termination as provided in paragraphs 8 and 9 hereof.

         5. Exercise of Option. The Option may be exercised by Participant at
any time and from time to time after the Date of Grant, and through the
Expiration Date as to all or any part of the shares of the Stock then vested by
delivery to the Company of written notice of exercise and payment of the
purchase price as provided in paragraphs 5 and 6 hereof.

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         6. Method of Exercising Option. Subject to the terms and conditions of
this Option Agreement, the Option may be exercised by timely delivery to the
Company of written notice, which notice shall be effective on the date received
by the Company (the "Effective Date"). The notice shall state Participant's
election to exercise the Option, the number of shares in respect of which an
election to exercise has been made, the method of payment elected (see paragraph
7 hereof), the exact name or names in which the shares will be registered and
the Social Security number of Participant. Such notice shall be signed by the
Participant and shall be accompanied by payment of the purchase price of such
shares. In the event the Option shall be exercised by a person or persons other
than Participant pursuant to paragraph 9 hereof, such notice shall be signed by
such other person or persons and shall be accompanied by proof acceptable to the
Company of the legal right of such person or persons to exercise the Option. All
shares delivered by the Company upon exercise of the Option as provided herein
shall be fully paid and nonassessable upon delivery.

         7. Method of Payment for Options. Payment for shares purchased upon the
exercise of the Option shall be made by the Participant in cash or such other
method permitted by the Committee in its sole discretion, including (i)
tendering shares, (ii) surrendering a stock award valued at Fair Market Value on
the date of surrender, (iii) authorizing a third party to sell the shares (or a
sufficient portion thereof) acquired upon exercise of a stock option and
assigning the delivery to the Company of a sufficient amount of the sale
proceeds to pay for all the shares acquired through such exercise, or (iv) any
combination of the above. For purposes of this Agreement, "Fair Market Value"
means with respect to Stock or any other property, the fair market value of such
Stock or other property as determined by the Committee in its discretion, under
one of the following methods: (i) the average of the closing bid and asked
prices for the Stock as reported on any national securities exchange on which
the Stock is then listed (which shall include the Nasdaq National Market) for
that date or, if no prices are so reported for that date, such prices on the
next preceding date for which closing bid and asked prices were reported; or
(ii) the price as determined by such methods or procedures as may be established
from time to time by the Committee.

         8. Termination of Employment. In the event that Participant is
terminated as an Participant of or consultant to the Company for any reason
other than for Cause, as defined below, then Participant may at any time within
three (3) months next succeeding the effective date of such termination exercise
the Option to the extent that Participant was entitled to exercise the Option at
the date of termination, provided that in no event shall the Option, or any part
thereof, be exercisable after the Expiration Date. If Participant's employment
is terminated for Cause, the Option shall lapse at the time of such termination.
For purposes of this Agreement, "Cause" means if the Committee, in its
reasonable and good faith discretion, determines that Participant (i) has
developed or pursued interests substantially adverse to the Company, (ii)
materially breached any employment, engagement or confidentiality agreement or
otherwise failed to satisfactorily discharge his or her duties, (iii) has not
devoted all or substantially all of his or her business time, effort and
attention to the affairs of the Company (or such lesser amount as has been
agreed to in writing by the Company), (iv) is convicted of a felony involving
moral turpitude, or (v) has engaged in activities or omissions that are
detrimental to the well-being of the Company.

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         9. Death of Participant. In the event of the death of Participant
within a period during which the Option, or any part thereof, could have been
exercised by Participant, including three (3) months after the date of
Participants death (the "Option Period"), the Option shall lapse unless it is
exercised within the Option Period and in no event later than fifteen (15)
months after the date of Participant's death by the Participant's legal
representative or representatives or by the person or persons entitled to do so
under Participant's last will and testament or, if the Participant fails to make
a testamentary disposition of such Option or shall die intestate, by the person
or persons entitled to receive such Option under the applicable laws of descent
and distribution. An Option may be exercised following the death of the
Participant only if the Option was exercisable by the Participant immediately
prior to his or her death. In no event shall the Option, or any part thereof, be
exercisable after the Expiration Date. The Committee shall have the right to
require evidence satisfactory to it of the rights of any person or persons
seeking to exercise the Option under this paragraph 9 to exercise the Option.

         10. Nontransferability. The Option granted by this Option Agreement
shall be exercisable only during the term of the Option provided in paragraph 4
hereof and, except as provided in paragraphs 8 and 9 above, only by Participant
during his lifetime and while an Participant of the Company. No right or
interest of Participant in the option may be pledged, encumbered, or
hypothecated to or in favor of any party other than the Company, or shall be
subject to any lien, obligation, or liability of Participant to any other party
other than the Company.

         11. Delivery of Shares. No shares of Stock shall be delivered upon
exercise of the Option until (i) the purchase price shall have been paid in full
in the manner herein provided; (ii) applicable taxes required to be withheld
have been paid or withheld in full; (iii) approval of any governmental authority
required in connection with the Option, or the issuance of shares thereunder,
has been received by the Company; and (iv) if required by the Committee,
Participant has delivered to the Committee an Investment Letter in form and
content satisfactory to the Company as provided in paragraph 14 hereof.

         12. Adjustments. In the event a stock dividend is declared upon the
Stock, the shares of Stock then subject to the Option shall be increased
proportionately without any change in the aggregate purchase price therefor. In
the event the Stock shall be changed into or exchanged for a different number or
class of shares of Stock or of another corporation, whether through
reorganization, recapitalization, stock split-up, combination of shares, there
shall be substituted for each such share of Stock then subject to the Option the
number and class of shares of Stock into which each outstanding share of Stock
shall be so exchanged, all without any change in the aggregate purchase price
for the shares then subject to the Option.

         13. Change of Control. A Change of Control shall, in the sole
discretion of the Committee:

                  (a) cause the Option to become fully exercisable and all
         restrictions to lapse and allow Participant the right to exercise the
         Option prior to the occurrence of the event otherwise terminating the
         Option over such period as the Committee, in its sole and absolute
         discretion, shall determine; or

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                  (b) cause the Option to terminate, provided that the surviving
         or resulting corporation shall tender an option or options to purchase
         its shares or exercise such rights on terms and conditions, as to the
         number of shares and rights and otherwise, which shall substantially
         preserve the rights and benefits of Participant under this Agreement.

For purposes of this Agreement, "Change in Control" means and includes each of
the following: (i) there shall be consummated any consolidation or merger of the
Company in which the Company is not the continuing or surviving entity, or
pursuant to which Stock would be converted into cash, securities, or other
property, other than a merger of the Company in which the holders of the
Company's Stock immediately prior to the merger have the same proportionate
ownership of beneficial interest of common stock or other voting securities of
the surviving entity immediately after the merger; (ii) there shall be
consummated any sale, lease, exchange or other transfer (in one transaction or a
series of related transactions) of assets or earning power aggregating more than
40% of the assets or earning power of the Company and its subsidiaries (taken as
a whole); (iii) the shareholders of the Company shall approve any plan or
proposal for liquidation or dissolution of the Company; (iv) any person (as such
term is used in Sections 13(d) and 14(d)(2) of the Exchange Act) other than any
Participant benefit plan of the Company or any subsidiary of the Company or any
entity holding shares of capital stock of the Company for or pursuant to the
terms of any such Participant benefit plan in its role as an agent or trustee
for such plan, shall become the beneficial owner (within the meaning of Rule
13d-3 under the Exchange Act) of 20%; or (v) during any period of two
consecutive years, individuals who were directors of the Company at the
beginning of such period shall fail to constitute a majority of the Company's
Board of Directors, unless the election, or the nomination for election by the
Company's shareholders, of each new director was approved by a vote of at least
two-thirds of the directors then still in office who were directors at the
beginning of the period.

         14. Securities Act. The Company shall have the right, but not the
obligation, to cause the shares of Stock issuable upon exercise of the Option to
be registered under the appropriate rules and regulations of the Securities and
Exchange Commission. The Company shall not be required to deliver any shares of
Stock pursuant to the exercise of all or any part of the Option if, in the
opinion of counsel for the Company, such issuance would violate the Securities
Act of 1933 or any other applicable federal or state securities laws or
regulations. The Committee may require that Participant, prior to the issuance
of any such shares pursuant to exercise of the Option, sign and deliver to the
Company a written statement ("Investment Letter") stating (i) that Participant
is purchasing the shares for investment and not with a view to the sale or
distribution thereof; (ii) that Participant will not sell any shares received
upon exercise of the Option or any other shares of the Company that Participant
may then own or thereafter acquire except either (a) through a broker on a
national securities exchange or (b) with the prior written approval of the
Company; and (iii) containing such other terms and conditions as counsel for the
Company may reasonably require to assure compliance with the Securities Act of
1933 or other applicable federal or state securities laws and regulations. Such
Investment Letter shall be in form and content acceptable to the Committee in
its sole discretion. If shares of Stock or other securities issuable pursuant to
the exercise of the Option have not been registered under the Securities Act of
1933 or other applicable federal or state securities laws or regulations, such
shares shall bear a legend restricting the transferability thereof, such legend
to be substantially in the following form:

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                  "The shares represented by this certificate have not been
                  registered or qualified under federal or state securities
                  laws. The shares may not be offered for sale, sold, pledged or
                  otherwise disposed of unless so registered or qualified,
                  unless an exemption exists or unless such disposition is not
                  subject to the federal or state securities laws, and the
                  availability of any exemption or the inapplicability of such
                  securities laws must be established by an opinion of counsel,
                  which opinion and counsel shall both be reasonably
                  satisfactory to the Company."

         15. Federal and State Taxes. Upon exercise of the Option, or any part
thereof, Participant may incur certain liabilities for federal, state or local
taxes and the Company may be required by law to withhold such taxes for payment
to taxing authorities. Upon determination by the Company of the amount of taxes
required to be withheld, if any, with respect to the shares to be issued
pursuant to the exercise of the Option, Participant shall pay all Federal state
and local tax withholding requirements by having the Company withhold Stock (to
the extent that Stock is issued pursuant to the Award) having a Fair Market
Value on the date that tax is to be determined equal to the tax otherwise
required to be withheld.

         16. Administration. This Option Agreement shall at all times be
administered by the Committee and decisions of the majority of the Committee
with respect thereto and to this Option Agreement shall be final and binding
upon Participant and the Company.

         17. Obligation to Exercise. Participant shall have no obligation to
exercise any option granted by this Agreement.

         18. Governing Law. This Option Agreement shall be interpreted and
administered under the laws of the State of Arizona without regard to conflict
of law principles.

         19. Amendments. This Option Agreement may be amended only by a written
agreement executed by the Company and Participant. The Company and Participant
acknowledge that changes in federal tax laws enacted subsequent to the Date of
Grant, and applicable to stock options, may provide for tax benefits to the
Company or Participant. In any such event, the Company and Participant agree
that this Option Agreement may be amended as necessary to secure for the Company
and Participant any benefits that may result from such legislation. Any such
amendment shall be made only upon the mutual consent of the parties, which
consent (of either party) may be withheld for any reason.

         IN WITNESS WHEREOF, the Company has caused this Option Agreement to be
duly executed and Participant has hereunto set his or her hand as of the date
first written above.

                                             MICROTEST, INC.


                                             By ___________________________
                                                Its Chief Executive Officer

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