Document:

<PAGE>   1
                                                                     EXHIBIT 4.2

                      BROCADE COMMUNICATIONS SYSTEMS, INC.

                        1999 EMPLOYEE STOCK PURCHASE PLAN

        1. Purpose. The purpose of the Plan is to provide employees of the
Company and its Designated Subsidiaries with an opportunity to purchase Common
Stock of the Company through accumulated payroll deductions. It is the intention
of the Company to have the Plan qualify as an "Employee Stock Purchase Plan"
under Section 423 of the Internal Revenue Code of 1986, as amended. The
provisions of the Plan, accordingly, shall be construed so as to extend and
limit participation in a manner consistent with the requirements of that section
of the Code.

        2. Definitions.

               (a) "Board" shall mean the Board of Directors of the Company.

               (b) "Code" shall mean the Internal Revenue Code of 1986, as
amended.

               (c) "Common Stock" shall mean the Common Stock of the Company.

               (d) "Company" shall mean Brocade Communications Systems, Inc., a
Delaware corporation, and any Designated Subsidiary of the Company.

               (e) "Compensation" shall mean all base straight time gross
earnings and commissions, exclusive of payments for overtime, shift premium,
incentive compensation, incentive payments, cash bonuses, non-cash bonuses and
other compensation. Commencing on the first Trading Day for the Offering Period
beginning on December 1, 1999, Compensation shall also mean cash bonuses.

               (f) "Designated Subsidiary" shall mean any Subsidiary which has
been designated by the Board from time to time in its sole discretion as
eligible to participate in the Plan.

               (g) "Employee" shall mean any individual who is an Employee of
the Company for tax purposes whose customary employment with the Company is at
least twenty (20) hours per week and more than five (5) months in any calendar
year. For purposes of the Plan, the employment relationship shall be treated as
continuing intact while the individual is on sick leave or other leave of
absence approved by the Company. Where the period of leave exceeds 90 days and
the individual's right to reemployment is not guaranteed either by statute or by
contract, the employment relationship shall be deemed to have terminated on the
91st day of such leave.

               (h) "Enrollment Date" shall mean the first day of each Offering
Period.

               (i) "Exercise Date" shall mean the last day of each Offering
Period.

               (j) "Fair Market Value" shall mean, as of any date, the value of
Common Stock determined as follows:

<PAGE>   2
                      (i) If the Common Stock is listed on any established stock
exchange or a national market system, including without limitation the Nasdaq
National Market or The Nasdaq SmallCap Market of The Nasdaq Stock Market, its
Fair Market Value shall be the closing sales price for such stock (or the
closing bid, if no sales were reported) as quoted on such exchange or system for
the last market trading day on the date of such determination, as reported in
The Wall Street Journal or such other source as the Board deems reliable, or;

                      (ii) If the Common Stock is regularly quoted by a
recognized securities dealer but selling prices are not reported, its Fair
Market Value shall be the mean of the closing bid and asked prices for the
Common Stock on the date of such determination, as reported in The Wall Street
Journal or such other source as the Board deems reliable, or;

                      (iii) In the absence of an established market for the
Common Stock, the Fair Market Value thereof shall be determined in good faith by
the Board.

                      (iv) For purposes of the Enrollment Date of the first
Offering Period under the Plan, the Fair Market Value shall be the initial price
to the public as set forth in the final prospectus included within the
registration statement in Form S-1 filed with the Securities and Exchange
Commission for the initial public offering of the Company's Common Stock (the
"Registration Statement").

               (k) "Offering Period" shall mean a period of approximately six
(6) months during which an option granted pursuant to the Plan may be exercised,
commencing on the first Trading Day on or after June 1 and terminating on the
last Trading Day in the period ending the following November 30, or commencing
on the first Trading Day on or after December 1 and terminating on the last
Trading Day in the period ending the following May 31; provided, however, that
the first Offering Period under the Plan shall commence with the first Trading
Day on or after the date on which the Securities and Exchange Commission
declares the Company's Registration Statement effective and ending on the last
Trading Day on or before November 30, 1999. The duration of Offering Periods may
be changed pursuant to Section 4 of this Plan.

               (l) "Plan" shall mean this Employee Stock Purchase Plan.

               (m) "Purchase Price" shall mean an amount equal to 85% of the
Fair Market Value of a share of Common Stock on the Enrollment Date or on the
Exercise Date, whichever is lower; provided, however, that the Purchase Price
may be adjusted by the Board pursuant to Section 20.

               (n) "Reserves" shall mean the number of shares of Common Stock
covered by each option under the Plan which have not yet been exercised and the
number of shares of Common Stock which have been authorized for issuance under
the Plan but not yet placed under option.

                                       2

<PAGE>   3
               (o) "Subsidiary" shall mean a corporation, domestic or foreign,
of which not less than 50% of the voting shares are held by the Company or a
Subsidiary, whether or not such corporation now exists or is hereafter organized
or acquired by the Company or a Subsidiary.

               (p) "Trading Day" shall mean a day on which national stock
exchanges and the Nasdaq System are open for trading.

        3. Eligibility.

               (a) Any Employee who shall be employed by the Company on a given
Enrollment Date shall be eligible to participate in the Plan.

               (b) Any provisions of the Plan to the contrary notwithstanding,
no Employee shall be granted an option under the Plan (i) to the extent that,
immediately after the grant, such Employee (or any other person whose stock
would be attributed to such Employee pursuant to Section 424(d) of the Code)
would own capital stock of the Company and/or hold outstanding options to
purchase such stock possessing five percent (5%) or more of the total combined
voting power or value of all classes of the capital stock of the Company or of
any Subsidiary, or (ii) to the extent that his or her rights to purchase stock
under all employee stock purchase plans of the Company and its subsidiaries
accrues at a rate which exceeds Twenty-Five Thousand Dollars ($25,000) worth of
stock (determined at the fair market value of the shares at the time such option
is granted) for each calendar year in which such option is outstanding at any
time.

        4. Offering Periods. The Plan shall be implemented by consecutive
Offering Periods with a new Offering Period commencing on the first Trading Day
on or after June 1 and December 1 each year, or on such other date as the Board
shall determine, and continuing thereafter until terminated in accordance with
Section 20 hereof; provided, however, that the first Offering Period under the
Plan shall commence with the first Trading Day on or after the date on which the
Securities and Exchange Commission declares the Company's Registration Statement
effective and ending on the last Trading Day on or before November 30, 1999. The
Board shall have the power to change the duration of Offering Periods (including
the commencement dates thereof) with respect to future offerings without
stockholder approval if such change is announced at least five (5) days prior to
the scheduled beginning of the first Offering Period to be affected thereafter.

        5. Participation.

               (a) An eligible Employee may become a participant in the Plan by
completing a subscription agreement authorizing payroll deductions in the form
of Exhibit A to this Plan and filing it with the Company's payroll office prior
to the applicable Enrollment Date.

               (b) Payroll deductions for a participant shall commence on the
first payroll following the Enrollment Date and shall end on the last payroll in
the Offering Period to which such authorization is applicable, unless sooner
terminated by the participant as provided in Section 10 hereof.

                                       3

<PAGE>   4
        6. Payroll Deductions.

               (a) At the time a participant files his or her subscription
agreement, he or she shall elect to have payroll deductions made on each pay day
during the Offering Period in an amount not exceeding fifteen percent (15%) of
the Compensation which he or she receives on each pay day during the Offering
Period.

               (b) All payroll deductions made for a participant shall be
credited to his or her account under the Plan and shall be withheld in whole
percentages only. A participant may not make any additional payments into such
account.

               (c) A participant may discontinue his or her participation in the
Plan as provided in Section 10 hereof, or may increase or decrease the rate of
his or her payroll deductions during the Offering Period by completing or filing
with the Company a new subscription agreement authorizing a change in payroll
deduction rate. The Board may, in its discretion, limit the number of
participation rate changes during any Offering Period. The change in rate shall
be effective with the first full payroll period following five (5) business days
after the Company's receipt of the new subscription agreement unless the Company
elects to process a given change in participation more quickly. A participant's
subscription agreement shall remain in effect for successive Offering Periods
unless terminated as provided in Section 10 hereof.

               (d) Notwithstanding the foregoing, to the extent necessary to
comply with Section 423(b)(8) of the Code and Section 3(b) hereof, a
participant's payroll deductions may be decreased to zero percent (0%) at any
time during an Offering Period. Payroll deductions shall recommence at the rate
provided in such participant's subscription agreement at the beginning of the
first Offering Period which is scheduled to end in the following calendar year,
unless terminated by the participant as provided in Section 10 hereof.

               (e) At the time the option is exercised, in whole or in part, or
at the time some or all of the Company's Common Stock issued under the Plan is
disposed of, the participant must make adequate provision for the Company's
federal, state, or other tax withholding obligations, if any, which arise upon
the exercise of the option or the disposition of the Common Stock. At any time,
the Company may, but shall not be obligated to, withhold from the participant's
compensation the amount necessary for the Company to meet applicable withholding
obligations, including any withholding required to make available to the Company
any tax deductions or benefits attributable to sale or early disposition of
Common Stock by the Employee.

        7. Grant of Option. On the Enrollment Date of each Offering Period, each
eligible Employee participating in such Offering Period shall be granted an
option to purchase on the Exercise Date of such Offering Period (at the
applicable Purchase Price) up to a number of shares of the Company's Common
Stock determined by dividing such Employee's payroll deductions accumulated
prior to such Exercise Date and retained in the Participant's account as of the
Exercise Date by the applicable Purchase Price; provided that in no event shall
an Employee be permitted to purchase during each Offering Period more than 3000
shares (subject to any adjustment pursuant to Section 19), and provided further
that such purchase shall be subject to the limitations set forth in

                                       4

<PAGE>   5
Sections 3(b) and 12 hereof. Exercise of the option shall occur as provided in
Section 8 hereof, unless the participant has withdrawn pursuant to Section 10
hereof. The Option shall expire on the last day of the Offering Period.

        8. Exercise of Option. Unless a participant withdraws from the Plan as
provided in Section 10 hereof, his or her option for the purchase of shares
shall be exercised automatically on the Exercise Date, and the maximum number of
full shares subject to option shall be purchased for such participant at the
applicable Purchase Price with the accumulated payroll deductions in his or her
account. No fractional shares shall be purchased; any payroll deductions
accumulated in a participant's account which are not sufficient to purchase a
full share shall be retained in the participant's account for the subsequent
Offering Period, subject to earlier withdrawal by the participant as provided in
Section 10 hereof. Any other monies left over in a participant's account after
the Exercise Date shall be returned to the participant. During a participant's
lifetime, a participant's option to purchase shares hereunder is exercisable
only by him or her.

        9. Delivery. As promptly as practicable after each Exercise Date on
which a purchase of shares occurs, the Company shall arrange the delivery to
each participant, as appropriate, the shares purchased upon exercise of his or
her option.

        10. Withdrawal.

               (a) A participant may withdraw all but not less than all the
payroll deductions credited to his or her account and not yet used to exercise
his or her option under the Plan at any time by giving written notice to the
Company in the form of Exhibit B to this Plan. All of the participant's payroll
deductions credited to his or her account shall be paid to such participant
promptly after receipt of notice of withdrawal and such participant's option for
the Offering Period shall be automatically terminated, and no further payroll
deductions for the purchase of shares shall be made for such Offering Period. If
a participant withdraws from an Offering Period, payroll deductions shall not
resume at the beginning of the succeeding Offering Period unless the participant
delivers to the Company a new subscription agreement.

               (b) A participant's withdrawal from an Offering Period shall not
have any effect upon his or her eligibility to participate in any similar plan
which may hereafter be adopted by the Company or in succeeding Offering Periods
which commence after the termination of the Offering Period from which the
participant withdraws.

        11. Termination of Employment. Upon a participant's ceasing to be an
Employee for any reason, he or she shall be deemed to have elected to withdraw
from the Plan and the payroll deductions credited to such participant's account
during the Offering Period but not yet used to exercise the option shall be
returned to such participant or, in the case of his or her death, to the person
or persons entitled thereto under Section 15 hereof, and such participant's
option shall be automatically terminated. The preceding sentence
notwithstanding, a participant who receives payment in lieu of notice of
termination of employment shall be treated as continuing to be an Employee for
the participant's customary number of hours per week of employment during the
period in which the participant is subject to such payment in lieu of notice.

                                       5

<PAGE>   6
        12. Interest. No interest shall accrue on the payroll deductions of a
participant in the Plan.

        13. Stock.

               (a) Subject to adjustment upon changes in capitalization of the
Company as provided in Section 19 hereof, the maximum number of shares of the
Company's Common Stock which shall be made available for sale under the Plan
shall be 200,000 shares, plus an annual increase to be added on the first day of
the Company's fiscal year beginning in 2000 equal to the lesser of (i) 2,500,000
shares, (ii) 2.5% of the outstanding shares on such date or (iii) a lesser
amount determined by the Board. If, on a given Exercise Date, the number of
shares with respect to which options are to be exercised exceeds the number of
shares then available under the Plan, the Company shall make a pro rata
allocation of the shares remaining available for purchase in as uniform a manner
as shall be practicable and as it shall determine to be equitable.

               (b) The participant shall have no interest or voting right in
shares covered by his option until such option has been exercised.

               (c) Shares to be delivered to a participant under the Plan shall
be registered in the name of the participant or in the name of the participant
and his or her spouse.

        14. Administration. The Plan shall be administered by the Board or a
committee of members of the Board appointed by the Board. The Board or its
committee shall have full and exclusive discretionary authority to construe,
interpret and apply the terms of the Plan, to determine eligibility and to
adjudicate all disputed claims filed under the Plan. Every finding, decision and
determination made by the Board or its committee shall, to the full extent
permitted by law, be final and binding upon all parties.

        15. Designation of Beneficiary.

               (a) A participant may file a written designation of a beneficiary
who is to receive any shares and cash, if any, from the participant's account
under the Plan in the event of such participant's death subsequent to an
Exercise Date on which the option is exercised but prior to delivery to such
participant of such shares and cash. In addition, a participant may file a
written designation of a beneficiary who is to receive any cash from the
participant's account under the Plan in the event of such participant's death
prior to exercise of the option. If a participant is married and the designated
beneficiary is not the spouse, spousal consent shall be required for such
designation to be effective.

               (b) Such designation of beneficiary may be changed by the
participant at any time by written notice. In the event of the death of a
participant and in the absence of a beneficiary validly designated under the
Plan who is living at the time of such participant's death, the Company shall
deliver such shares and/or cash to the executor or administrator of the estate
of the participant, or if no such executor or administrator has been appointed
(to the knowledge of the Company), the Company, in its discretion, may deliver
such shares and/or cash to the spouse or to any one or more

                                       6

<PAGE>   7
dependents or relatives of the participant, or if no spouse, dependent or
relative is known to the Company, then to such other person as the Company may
designate.

        16. Transferability. Neither payroll deductions credited to a
participant's account nor any rights with regard to the exercise of an option or
to receive shares under the Plan may be assigned, transferred, pledged or
otherwise disposed of in any way (other than by will, the laws of descent and
distribution or as provided in Section 15 hereof) by the participant. Any such
attempt at assignment, transfer, pledge or other disposition shall be without
effect, except that the Company may treat such act as an election to withdraw
funds from an Offering Period in accordance with Section 10 hereof.

        17. Use of Funds. All payroll deductions received or held by the Company
under the Plan may be used by the Company for any corporate purpose, and the
Company shall not be obligated to segregate such payroll deductions.

        18. Reports. Individual accounts shall be maintained for each
participant in the Plan. Statements of account shall be given to participating
Employees at least annually, which statements shall set forth the amounts of
payroll deductions, the Purchase Price, the number of shares purchased and the
remaining cash balance, if any.

        19. Adjustments Upon Changes in Capitalization, Dissolution,
            Liquidation, Merger or Asset Sale.

               (a) Changes in Capitalization. Subject to any required action by
the stockholders of the Company, the Reserves, the maximum number of shares each
participant may purchase per Offering Period (pursuant to Section 7), as well as
the price per share and the number of shares of Common Stock covered by each
option under the Plan which has not yet been exercised shall be proportionately
adjusted for any increase or decrease in the number of issued shares of Common
Stock resulting from a stock split, reverse stock split, stock dividend,
combination or reclassification of the Common Stock, or any other increase or
decrease in the number of shares of Common Stock effected without receipt of
consideration by the Company; provided, however, that conversion of any
convertible securities of the Company shall not be deemed to have been "effected
without receipt of consideration". Such adjustment shall be made by the Board,
whose determination in that respect shall be final, binding and conclusive.
Except as expressly provided herein, no issuance by the Company of shares of
stock of any class, or securities convertible into shares of stock of any class,
shall affect, and no adjustment by reason thereof shall be made with respect to,
the number or price of shares of Common Stock subject to an option.

               (b) Dissolution or Liquidation. In the event of the proposed
dissolution or liquidation of the Company, the Offering Period then in progress
shall be shortened by setting a new Exercise Date (the "New Exercise Date"), and
shall terminate immediately prior to the consummation of such proposed
dissolution or liquidation, unless provided otherwise by the Board. The New
Exercise Date shall be before the date of the Company's proposed dissolution or
liquidation. The Board shall notify each participant in writing, at least ten
(10) business days prior to the New Exercise Date, that the Exercise Date for
the participant's option has been changed to the

                                       7

<PAGE>   8
New Exercise Date and that the participant's option shall be exercised
automatically on the New Exercise Date, unless prior to such date the
participant has withdrawn from the Offering Period as provided in Section 10
hereof.

               (c) Merger or Asset Sale. In the event of a proposed sale of all
or substantially all of the assets of the Company, or the merger of the Company
with or into another corporation, each outstanding option shall be assumed or an
equivalent option substituted by the successor corporation or a Parent or
Subsidiary of the successor corporation. In the event that the successor
corporation refuses to assume or substitute for the option, the Offering Period
then in progress shall be shortened by setting a new Exercise Date (the "New
Exercise Date"). The New Exercise Date shall be before the date of the Company's
proposed sale or merger. The Board shall notify each participant in writing, at
least ten (10) business days prior to the New Exercise Date, that the Exercise
Date for the participant's option has been changed to the New Exercise Date and
that the participant's option shall be exercised automatically on the New
Exercise Date, unless prior to such date the participant has withdrawn from the
Offering Period as provided in Section 10 hereof.

        20. Amendment or Termination.

               (a) The Board of Directors of the Company may at any time and for
any reason terminate or amend the Plan. Except as provided in Section 19 hereof,
no such termination can affect options previously granted, provided that an
Offering Period may be terminated by the Board of Directors on any Exercise Date
if the Board determines that the termination of the Offering Period or the Plan
is in the best interests of the Company and its stockholders. Except as provided
in Section 19 and Section 20 hereof, no amendment may make any change in any
option theretofore granted which adversely affects the rights of any
participant. To the extent necessary to comply with Section 423 of the Code (or
any other applicable law, regulation or stock exchange rule), the Company shall
obtain shareholder approval in such a manner and to such a degree as required.

               (b) Without stockholder consent and without regard to whether any
participant rights may be considered to have been "adversely affected," the
Board (or its committee) shall be entitled to change the Offering Periods, limit
the frequency and/or number of changes in the amount withheld during an Offering
Period, establish the exchange ratio applicable to amounts withheld in a
currency other than U.S. dollars, permit payroll withholding in excess of the
amount designated by a participant in order to adjust for delays or mistakes in
the Company's processing of properly completed withholding elections, establish
reasonable waiting and adjustment periods and/or accounting and crediting
procedures to ensure that amounts applied toward the purchase of Common Stock
for each participant properly correspond with amounts withheld from the
participant's Compensation, and establish such other limitations or procedures
as the Board (or its committee) determines in its sole discretion advisable
which are consistent with the Plan.

               (c) In the event the Board determines that the ongoing operation
of the Plan may result in unfavorable financial accounting consequences, the
Board may, in its discretion and, to the extent necessary or desirable, modify
or amend the Plan to reduce or eliminate such accounting consequence including,
but not limited to:

                                       8

<PAGE>   9
                      (i) altering the Purchase Price for any Offering Period
including an Offering Period underway at the time of the change in Purchase
Price;

                      (ii) shortening any Offering Period so that Offering
Period ends on a new Exercise Date, including an Offering Period underway at the
time of the Board action; and

                      (iii) allocating shares.

        Such modifications or amendments shall not require stockholder approval
or the consent of any Plan participants.

        21. Notices. All notices or other communications by a participant to the
Company under or in connection with the Plan shall be deemed to have been duly
given when received in the form specified by the Company at the location, or by
the person, designated by the Company for the receipt thereof.

        22. Conditions Upon Issuance of Shares. Shares shall not be issued with
respect to an option unless the exercise of such option and the issuance and
delivery of such shares pursuant thereto shall comply with all applicable
provisions of law, domestic or foreign, including, without limitation, the
Securities Act of 1933, as amended, the Securities Exchange Act of 1934, as
amended, the rules and regulations promulgated thereunder, and the requirements
of any stock exchange upon which the shares may then be listed, and shall be
further subject to the approval of counsel for the Company with respect to such
compliance.

        As a condition to the exercise of an option, the Company may require the
person exercising such option to represent and warrant at the time of any such
exercise that the shares are being purchased only for investment and without any
present intention to sell or distribute such shares if, in the opinion of
counsel for the Company, such a representation is required by any of the
aforementioned applicable provisions of law.

        23. Term of Plan. The Plan shall become effective upon the earlier to
occur of its adoption by the Board of Directors or its approval by the
stockholders of the Company. It shall continue in effect for a term of ten (10)
years unless sooner terminated under Section 20 hereof.

                                       9

<PAGE>   10
                                    EXHIBIT A

                      BROCADE COMMUNICATIONS SYSTEMS, INC.

                        1999 EMPLOYEE STOCK PURCHASE PLAN

                             SUBSCRIPTION AGREEMENT

        _____ Original Application                     Enrollment Date: _______

        _____ Change in Payroll Deduction Rate

        _____ Change of Beneficiary(ies)

        1. _____________________________________ hereby elects to participate in
the Brocade Communications Systems, Inc. 1999 Employee Stock Purchase Plan (the
"Employee Stock Purchase Plan") and subscribes to purchase shares of the
Company's Common Stock in accordance with this Subscription Agreement and the
Employee Stock Purchase Plan.

        2. I hereby authorize payroll deductions from each paycheck in the
amount of ____% of my Compensation on each payday (from 1 to 15%) during the
Offering Period in accordance with the Employee Stock Purchase Plan. (Please
note that no fractional percentages are permitted.)

        3. I understand that said payroll deductions shall be accumulated for
the purchase of shares of Common Stock at the applicable Purchase Price
determined in accordance with the Employee Stock Purchase Plan. I understand
that if I do not withdraw from an Offering Period, any accumulated payroll
deductions will be used to automatically exercise my option.

        4. I have received a copy of the complete Employee Stock Purchase Plan.
I understand that my participation in the Employee Stock Purchase Plan is in all
respects subject to the terms of the Plan. I understand that my ability to
exercise the option under this Subscription Agreement is subject to stockholder
approval of the Employee Stock Purchase Plan.

        5. Shares purchased for me under the Employee Stock Purchase Plan should
be issued in the name(s) of (Employee or Employee and Spouse only):.

        6. I understand that if I dispose of any shares received by me pursuant
to the Plan within 2 years after the Enrollment Date (the first day of the
Offering Period during which I purchased such shares), I will be treated for
federal income tax purposes as having received ordinary income at the

<PAGE>   11
time of such disposition in an amount equal to the excess of the fair market
value of the shares at the time such shares were purchased by me over the price
which I paid for the shares. I hereby agree to notify the Company in writing
within 30 days after the date of any disposition of shares and I will make
adequate provision for Federal, state or other tax withholding obligations, if
any, which arise upon the disposition of the Common Stock. The Company may, but
will not be obligated to, withhold from my compensation the amount necessary to
meet any applicable withholding obligation including any withholding necessary
to make available to the Company any tax deductions or benefits attributable to
sale or early disposition of Common Stock by me. If I dispose of such shares at
any time after the expiration of the 2-year holding period, I understand that I
will be treated for federal income tax purposes as having received income only
at the time of such disposition, and that such income will be taxed as ordinary
income only to the extent of an amount equal to the lesser of (1) the excess of
the fair market value of the shares at the time of such disposition over the
purchase price which I paid for the shares, or (2) 15% of the fair market value
of the shares on the first day of the Offering Period. The remainder of the
gain, if any, recognized on such disposition will be taxed as capital gain.

        7. I hereby agree to be bound by the terms of the Employee Stock
Purchase Plan. The effectiveness of this Subscription Agreement is dependent
upon my eligibility to participate in the Employee Stock Purchase Plan.

        8. In the event of my death, I hereby designate the following as my
beneficiary(ies) to receive all payments and shares due me under the Employee
Stock Purchase Plan

NAME:  (Please print)
                      ---------------------------------------------------------
                        (First)          (Middle)                 (Last)

--------------------------------------------------
Relationship

--------------------------------------------------
(Address)

Employee's Social Security Number:
                                   -------------------------------

Employee's Address:
                      -------------------------------------------------

                      -------------------------------------------------

                      -----------------------------------------------

                                       2

<PAGE>   12
        I UNDERSTAND THAT THIS SUBSCRIPTION AGREEMENT SHALL REMAIN IN EFFECT
THROUGHOUT SUCCESSIVE OFFERING PERIODS UNLESS TERMINATED BY ME.

Dated:
       ------------------------             ----------------------------------
                                            Signature of Employee

                                            ----------------------------------
                                            Spouse's Signature
                                            (If beneficiary other than spouse)

<PAGE>   13
                                    EXHIBIT B

                      BROCADE COMMUNICATIONS SYSTEMS, INC.

                        1999 EMPLOYEE STOCK PURCHASE PLAN

                              NOTICE OF WITHDRAWAL

        The undersigned participant in the Offering Period of the Brocade
Communications Systems, Inc. 1999 Employee Stock Purchase Plan which began on
___________, ______ (the "Enrollment Date") hereby notifies the Company that he
or she hereby withdraws from the Offering Period. He or she hereby directs the
Company to pay to the undersigned as promptly as practicable all the payroll
deductions credited to his or her account with respect to such Offering Period.
The undersigned understands and agrees that his or her option for such Offering
Period will be automatically terminated. The undersigned understands further
that no further payroll deductions will be made for the purchase of shares in
the current Offering Period and the undersigned shall be eligible to participate
in succeeding Offering Periods only by delivering to the Company a new
Subscription Agreement.

Name and Address of Participant:

------------------------------------

------------------------------------

------------------------------------

Signature:

------------------------------------

Date:
      -------------------------------<PAGE>   1

                                                                     EXHIBIT 4.4

                      BROCADE COMMUNICATIONS SYSTEMS, INC.

                       1999 NONSTATUTORY STOCK OPTION PLAN

     1. Purposes of the Plan. The purposes of this Nonstatutory Stock Option
Plan are:

        - to attract and retain the best available personnel for positions of
          substantial responsibility,

        - to provide additional incentive to Employees and Consultants, and

        - to promote the success of the Company's business.

     Options granted under the Plan will be Nonstatutory Stock Options.

     2. Definitions. As used herein, the following definitions shall apply:

          (a) "Administrator" means the Board or any of its Committees as shall
be administering the Plan, in accordance with Section 4 of the Plan.

          (b) "Applicable Laws" means the requirements relating to the
administration of stock option plans under U.S. state corporate laws, U.S.
federal and state securities laws, the Code, any stock exchange or quotation
system on which the Common Stock is listed or quoted and the applicable laws of
any foreign country or jurisdiction where Options are, or will be, granted under
the Plan.

          (c) "Board" means the Board of Directors of the Company.

          (d) "Code" means the Internal Revenue Code of 1986, as amended.

          (e) "Committee" means a committee of Directors appointed by the Board
in accordance with Section 4 of the Plan.

          (f) "Common Stock" means the Common Stock of the Company.

          (g) "Company" means Brocade Communications Systems, Inc.

          (h) "Consultant" means any person, including an advisor, engaged by
the Company or a Parent or Subsidiary to render services to such entity.

          (i) "Director" means a member of the Board.

          (j) "Disability" means total and permanent disability as defined in
Section 22(e)(3) of the Code.

<PAGE>   2

          (k) "Employee" means any person, including Officers, employed by the
Company or any Parent or Subsidiary of the Company. A Service Provider shall not
cease to be an Employee in the case of (i) any leave of absence approved by the
Company or (ii) transfers between locations of the Company or between the
Company, its Parent, any Subsidiary, or any successor. Neither service as a
Director nor payment of a director's fee by the Company shall be sufficient to
constitute "employment" by the Company.

          (l) "Exchange Act" means the Securities Exchange Act of 1934, as
amended.

          (m) "Fair Market Value" means, as of any date, the value of Common
Stock determined as follows:

               (i) If the Common Stock is listed on any established stock
exchange or a national market system, including without limitation the Nasdaq
National Market or The Nasdaq SmallCap Market of The Nasdaq Stock Market, its
Fair Market Value shall be the closing sales price for such stock (or the
closing bid, if no sales were reported) as quoted on such exchange or system for
the last market trading day prior to the time of determination, as reported in
The Wall Street Journal or such other source as the Administrator deems
reliable;

               (ii) If the Common Stock is regularly quoted by a recognized
securities dealer but selling prices are not reported, the Fair Market Value of
a Share of Common Stock shall be the mean between the high bid and low asked
prices for the Common Stock on the last market trading day prior to the day of
determination, as reported in The Wall Street Journal or such other source as
the Administrator deems reliable;

               (iii) In the absence of an established market for the Common
Stock, the Fair Market Value shall be determined in good faith by the
Administrator.

          (n) "Notice of Grant" means a written or electronic notice evidencing
certain terms and conditions of an individual Option grant. The Notice of Grant
is part of the Option Agreement.

          (o) "Officer" means a person who is an officer of the Company within
the meaning of Nasdaq guidelines, including all employees with the corporate
rank of vice-president or higher, and employees with lesser rank but comparable
authority.

          (p) "Option" means a nonstatutory stock option granted pursuant to the
Plan, that is not intended to qualify as an incentive stock option within the
meaning of Section 422 of the Code and the regulations promulgated thereunder.

          (q) "Option Agreement" means an agreement between the Company and an
Optionee evidencing the terms and conditions of an individual Option grant. The
Option Agreement is subject to the terms and conditions of the Plan.

                                      -2-
<PAGE>   3

          (r) "Optioned Stock" means the Common Stock subject to an Option.

          (s) "Optionee" means the holder of an outstanding Option granted under
the Plan.

          (t) "Parent" means a "parent corporation," whether now or hereafter
existing, as defined in Section 424(e) of the Code.

          (u) "Plan" means this 1999 Nonstatutory Stock Option Plan.

          (v) "Service Provider" means an Employee, Consultant or Director.

          (w) "Share" means a share of the Common Stock, as adjusted in
accordance with Section 12 of the Plan.

          (x) "Subsidiary" means a "subsidiary corporation," whether now or
hereafter existing, as defined in Section 424(f) of the Code.

     3. Stock Subject to the Plan. Subject to the provisions of Section 12 of
the Plan, the maximum aggregate number of Shares which may be optioned and sold
under the Plan is one million (1,000,000) Shares. The Shares may be authorized,
but unissued, or reacquired Common Stock.

     If an Option expires or becomes unexercisable without having been exercised
in full, the unpurchased Shares which were subject thereto shall become
available for future grant or sale under the Plan (unless the Plan has
terminated).

     4. Administration of the Plan.

          (a) Administration. The Plan shall be administered by (i) the Board or
(ii) a Committee, which Committee shall be constituted to satisfy Applicable
Laws.

          (b) Powers of the Administrator. Subject to the provisions of the
Plan, and in the case of a Committee, subject to the specific duties delegated
by the Board to such Committee, the Administrator shall have the authority, in
its discretion:

               (i) to determine the Fair Market Value of the Common Stock;

               (ii) to select the Service Providers to whom Options may be
granted hereunder;

               (iii) to determine whether and to what extent Options are granted
hereunder;

               (iv) to determine the number of shares of Common Stock to be
covered by each Option granted hereunder;

                                      -3-
<PAGE>   4

               (v) to approve forms of agreement for use under the Plan;

               (vi) to determine the terms and conditions, not inconsistent with
the terms of the Plan, of any award granted hereunder. Such terms and conditions
include, but are not limited to, the exercise price, the time or times when
Options may be exercised (which may be based on performance criteria), any
vesting acceleration or waiver of forfeiture restrictions, and any restriction
or limitation regarding any Option or the shares of Common Stock relating
thereto, based in each case on such factors as the Administrator, in its sole
discretion, shall determine;

               (vii) to construe and interpret the terms of the Plan and awards
granted pursuant to the Plan;

               (viii) to prescribe, amend and rescind rules and regulations
relating to the Plan, including rules and regulations relating to sub-plans
established for the purpose of qualifying for preferred tax treatment under
foreign tax laws;

               (ix) to modify or amend each Option (subject to Section 14(b) of
the Plan), including the discretionary authority to extend the post-termination
exercisability period of Options longer than is otherwise provided for in the
Plan;

               (x) to authorize any person to execute on behalf of the Company
any instrument required to effect the grant of an Option previously granted by
the Administrator;

               (xi) to determine the terms and restrictions applicable to
Options;

               (xii) to allow Optionees to satisfy withholding tax obligations
by electing to have the Company withhold from the Shares to be issued upon
exercise of an Option that number of Shares having a Fair Market Value equal to
the amount required to be withheld (but not more than the amount required to be
withheld). The Fair Market Value of the Shares to be withheld shall be
determined on the date that the amount of tax to be withheld is to be
determined. All elections by an Optionee to have Shares withheld for this
purpose shall be made in such form and under such conditions as the
Administrator may deem necessary or advisable; and

               (xiii) to make all other determinations deemed necessary or
advisable for administering the Plan.

          (c) Effect of Administrator's Decision. The Administrator's decisions,
determinations and interpretations shall be final and binding on all Optionees
and any other holders of Options.

     5. Eligibility. Options may be granted to Service Providers; provided,
however, that Options may not be granted to Officers and Directors, except as an
essential inducement to an Officer entering into an employment agreement
regarding his or her initial service with the Company.

                                      -4-
<PAGE>   5

     6. Limitation. Neither the Plan nor any Option shall confer upon an
Optionee any right with respect to continuing the Optionee's relationship as a
Service Provider with the Company, nor shall they interfere in any way with the
Optionee's right or the Company's right to terminate such relationship at any
time, with or without cause.

     7. Term of Plan. The Plan shall become effective upon its adoption by the
Board. It shall continue in effect for ten (10) years, unless sooner terminated
under Section 14 of the Plan.

     8. Term of Option. The term of each Option shall be stated in the Option
Agreement.

     9. Option Exercise Price and Consideration.

          (a) Exercise Price. The per share exercise price for the Shares to be
issued pursuant to exercise of an Option shall be determined by the
Administrator.

          (b) Waiting Period and Exercise Dates. At the time an Option is
granted, the Administrator shall fix the period within which the Option may be
exercised and shall determine any conditions which must be satisfied before the
Option may be exercised.

          (c) Form of Consideration. The Administrator shall determine the
acceptable form of consideration for exercising an Option, including the method
of payment. Such consideration may consist entirely of:

               (i) cash;

               (ii) check;

               (iii) promissory note;

               (iv) other Shares which (A) in the case of Shares acquired upon
exercise of an option, have been owned by the Optionee for more than six months
on the date of surrender, and (B) have a Fair Market Value on the date of
surrender equal to the aggregate exercise price of the Shares as to which said
Option shall be exercised;

               (v) consideration received by the Company under a cashless
exercise program implemented by the Company in connection with the Plan;

               (vi) such other consideration and method of payment for the
issuance of Shares to the extent permitted by Applicable Laws; or

               (vii) any combination of the foregoing methods of payment.

                                      -5-
<PAGE>   6

     10. Exercise of Option.

          (a) Procedure for Exercise; Rights as a Shareholder. Any Option
granted hereunder shall be exercisable according to the terms of the Plan and at
such times and under such conditions as determined by the Administrator and set
forth in the Option Agreement. An Option may not be exercised for a fraction of
a Share.

          An Option shall be deemed exercised when the Company receives: (i)
written or electronic notice of exercise (in accordance with the Option
Agreement) from the person entitled to exercise the Option, and (ii) full
payment for the Shares with respect to which the Option is exercised. Full
payment may consist of any consideration and method of payment authorized by the
Administrator and permitted by the Option Agreement and the Plan. Shares issued
upon exercise of an Option shall be issued in the name of the Optionee or, if
requested by the Optionee, in the name of the Optionee and his or her spouse.
Until the Shares are issued (as evidenced by the appropriate entry on the books
of the Company or of a duly authorized transfer agent of the Company), no right
to vote or receive dividends or any other rights as a shareholder shall exist
with respect to the Optioned Stock, notwithstanding the exercise of the Option.
The Company shall issue (or cause to be issued) such Shares promptly after the
Option is exercised. No adjustment will be made for a dividend or other right
for which the record date is prior to the date the Shares are issued, except as
provided in Section 12 of the Plan.

          Exercising an Option in any manner shall decrease the number of Shares
thereafter available, both for purposes of the Plan and for sale under the
Option, by the number of Shares as to which the Option is exercised.

          (b) Termination of Relationship as a Service Provider. If an Optionee
ceases to be a Service Provider, other than upon the Optionee's death or
Disability, the Optionee may exercise his or her Option, but only within such
period of time as is specified in the Option Agreement, and only to the extent
that the Option is vested on the date of termination (but in no event later than
the expiration of the term of such Option as set forth in the Option Agreement).
In the absence of a specified time in the Option Agreement, the Option shall
remain exercisable for three (3) months following the Optionee's termination.
If, on the date of termination, the Optionee is not vested as to his or her
entire Option, the Shares covered by the unvested portion of the Option shall
revert to the Plan. If, after termination, the Optionee does not exercise his or
her Option within the time specified by the Administrator, the Option shall
terminate, and the Shares covered by such Option shall revert to the Plan.

          (c) Disability of Optionee. If an Optionee ceases to be a Service
Provider as a result of the Optionee's Disability, the Optionee may exercise his
or her Option within such period of time as is specified in the Option
Agreement, to the extent the Option is vested on the date of termination (but in
no event later than the expiration of the term of such Option as set forth in
the Option Agreement). In the absence of a specified time in the Option
Agreement, the Option shall remain exercisable for twelve (12) months following
the Optionee's termination. If, on the date of

                                      -6-
<PAGE>   7

termination, the Optionee is not vested as to his or her entire Option, the
Shares covered by the unvested portion of the Option shall revert to the Plan.
If, after termination, the Optionee does not exercise his or her Option within
the time specified herein, the Option shall terminate, and the Shares covered by
such Option shall revert to the Plan.

          (d) Death of Optionee. If an Optionee dies while a Service Provider,
the Option may be exercised within such period of time as is specified in the
Option Agreement (but in no event later than the expiration of the term of such
Option as set forth in the Notice of Grant), by the Optionee's estate or by a
person who acquires the right to exercise the Option by bequest or inheritance,
but only to the extent that the Option is vested on the date of death. In the
absence of a specified time in the Option Agreement, the Option shall remain
exercisable for twelve (12) months following the Optionee's termination. If, at
the time of death, the Optionee is not vested as to his or her entire Option,
the Shares covered by the unvested portion of the Option shall immediately
revert to the Plan. The Option may be exercised by the executor or administrator
of the Optionee's estate or, if none, by the person(s) entitled to exercise the
Option under the Optionee's will or the laws of descent or distribution. If the
Option is not so exercised within the time specified herein, the Option shall
terminate, and the Shares covered by such Option shall revert to the Plan.

          (e) Buyout Provisions. The Administrator may at any time offer to buy
out for a payment in cash or Shares, an Option previously granted based on such
terms and conditions as the Administrator shall establish and communicate to the
Optionee at the time that such offer is made.

     11. Non-Transferability of Options. Unless determined otherwise by the
Administrator, an Option may not be sold, pledged, assigned, hypothecated,
transferred, or disposed of in any manner other than by will or by the laws of
descent or distribution and may be exercised, during the lifetime of the
Optionee, only by the Optionee. If the Administrator makes an Option
transferable, such Option shall contain such additional terms and conditions as
the Administrator deems appropriate.

     12. Adjustments Upon Changes in Capitalization, Dissolution, Merger or
Asset Sale.

          (a) Changes in Capitalization. Subject to any required action by the
shareholders of the Company, the number of shares of Common Stock covered by
each outstanding Option, and the number of shares of Common Stock which have
been authorized for issuance under the Plan but as to which no Options have yet
been granted or which have been returned to the Plan upon cancellation or
expiration of an Option, as well as the price per share of Common Stock covered
by each such outstanding Option, shall be proportionately adjusted for any
increase or decrease in the number of issued shares of Common Stock resulting
from a stock split, reverse stock split, stock dividend, combination or
reclassification of the Common Stock, or any other increase or decrease in the
number of issued shares of Common Stock effected without receipt of
consideration by the Company; provided, however, that conversion of any
convertible securities of the Company shall not be deemed to have been "effected
without receipt of consideration." Such adjustment shall be made by the Board,
whose determination in that respect shall be final, binding and conclusive.
Except as

                                      -7-
<PAGE>   8

expressly provided herein, no issuance by the Company of shares of stock of any
class, or securities convertible into shares of stock of any class, shall
affect, and no adjustment by reason thereof shall be made with respect to, the
number or price of shares of Common Stock subject to an Option.

          (b) Dissolution or Liquidation. In the event of the proposed
dissolution or liquidation of the Company, the Administrator shall notify each
Optionee as soon as practicable prior to the effective date of such proposed
transaction. The Administrator in its discretion may provide for an Optionee to
have the right to exercise his or her Option until ten (10) days prior to such
transaction as to all of the Optioned Stock covered thereby, including Shares as
to which the Option would not otherwise be exercisable. In addition, the
Administrator may provide that any Company repurchase option applicable to any
Shares purchased upon exercise of an Option shall lapse as to all such Shares,
provided the proposed dissolution or liquidation takes place at the time and in
the manner contemplated. To the extent it has not been previously exercised, an
Option will terminate immediately prior to the consummation of such proposed
action.

          (c) Merger or Asset Sale. In the event of a merger of the Company with
or into another corporation, or the sale of substantially all of the assets of
the Company, each outstanding Option shall be assumed or an equivalent option or
right substituted by the successor corporation or a Parent or Subsidiary of the
successor corporation. In the event that the successor corporation refuses to
assume or substitute for the Option, the Optionee shall fully vest in and have
the right to exercise the Option as to all of the Optioned Stock, including
Shares as to which it would not otherwise be vested or exercisable. If an Option
becomes fully vested and exercisable in lieu of assumption or substitution in
the event of a merger or sale of assets, the Administrator shall notify the
Optionee in writing or electronically that the Option shall be fully vested and
exercisable for a period of fifteen (15) days from the date of such notice, and
the Option shall terminate upon the expiration of such period. For the purposes
of this paragraph, the Option shall be considered assumed if, following the
merger or sale of assets, the option or right confers the right to purchase or
receive, for each Share of Optioned Stock, immediately prior to the merger or
sale of assets, the consideration (whether stock, cash, or other securities or
property) received in the merger or sale of assets by holders of Common Stock
for each Share held on the effective date of the transaction (and if holders
were offered a choice of consideration, the type of consideration chosen by the
holders of a majority of the outstanding Shares); provided, however, that if
such consideration received in the merger or sale of assets is not solely common
stock of the successor corporation or its Parent, the Administrator may, with
the consent of the successor corporation, provide for the consideration to be
received upon the exercise of the Option, for each Share of Optioned Stock to be
solely common stock of the successor corporation or its Parent equal in fair
market value to the per share consideration received by holders of Common Stock
in the merger or sale of assets.

     13. Date of Grant. The date of grant of an Option shall be, for all
purposes, the date on which the Administrator makes the determination granting
such Option, or such other later date as is determined by the Administrator.
Notice of the determination shall be provided to each Optionee within a
reasonable time after the date of such grant.

                                      -8-
<PAGE>   9

     14. Amendment and Termination of the Plan.

          (a) Amendment and Termination. The Board may at any time amend, alter,
suspend or terminate the Plan.

          (b) Effect of Amendment or Termination. No amendment, alteration,
suspension or termination of the Plan shall impair the rights of any Optionee,
unless mutually agreed otherwise between the Optionee and the Administrator,
which agreement must be in writing and signed by the Optionee and the Company.
Termination of the Plan shall not affect the Administrator's ability to exercise
the powers granted to it hereunder with respect to options granted under the
Plan prior to the date of such termination.

     15. Conditions Upon Issuance of Shares.

          (a) Legal Compliance. Shares shall not be issued pursuant to the
exercise of an Option unless the exercise of such Option and the issuance and
delivery of such Shares shall comply with Applicable Laws and shall be further
subject to the approval of counsel for the Company with respect to such
compliance.

          (b) Investment Representations. As a condition to the exercise of an
Option the Company may require the person exercising such Option to represent
and warrant at the time of any such exercise that the Shares are being purchased
only for investment and without any present intention to sell or distribute such
Shares if, in the opinion of counsel for the Company, such a representation is
required.

     16. Inability to Obtain Authority. The inability of the Company to obtain
authority from any regulatory body having jurisdiction, which authority is
deemed by the Company's counsel to be necessary to the lawful issuance and sale
of any Shares hereunder, shall relieve the Company of any liability in respect
of the failure to issue or sell such Shares as to which such requisite authority
shall not have been obtained.

     17. Reservation of Shares. The Company, during the term of this Plan, will
at all times reserve and keep available such number of Shares as shall be
sufficient to satisfy the requirements of the Plan.

                                      -9-
<PAGE>   10

                      BROCADE COMMUNICATIONS SYSTEMS, INC.

                       1999 NONSTATUTORY STOCK OPTION PLAN

                             STOCK OPTION AGREEMENT

     Unless otherwise defined herein, the terms defined in the Plan shall have
the same defined meanings in this Option Agreement.

I. NOTICE OF STOCK OPTION GRANT

     [OPTIONEE'S NAME AND ADDRESS]

     You have been granted an option to purchase Common Stock of the Company,
subject to the terms and conditions of the Plan and this Option Agreement, as
follows:

<TABLE>
<S>                                        <C>
        Grant Number                        __________________________

        Date of Grant                       __________________________

        Vesting Commencement Date           __________________________

        Exercise Price per Share            $_________________________

        Total Number of Shares Granted      __________________________

        Total Exercise Price                $_________________________

        Type of Option:                     Nonstatutory Stock Option

        Term/Expiration Date:               __________________________

        Vesting Schedule:
</TABLE>

     Subject to the Optionee continuing to be a Service Provider on such dates,
this Option shall vest and become exercisable in accordance with the following
schedule:

     25% of the Shares subject to the Option shall vest twelve months after the
Vesting Commencement Date, and 1/48th of the Shares subject to the Option shall
vest each full month thereafter, so as to be 100% vested and on the fourth
anniversary of the Vesting Commencement Date, subject to Optionee remaining a
Service Provider on such vesting dates.

<PAGE>   11

     Termination Period:

     This Option may be exercised for three months after Optionee ceases to be a
Service Provider. Upon the death or Disability of the Optionee, this Option may
be exercised for twelve months following Optionee's termination as a Service
Provider. In no event shall this Option be exercised later than the
Term/Expiration Date as provided above.

II. AGREEMENT

     1. Grant of Option. The Plan Administrator of the Company hereby grants to
the Optionee named in the Notice of Grant attached as Part I of this Agreement
(the "Optionee") an option (the "Option") to purchase the number of Shares, as
set forth in the Notice of Grant, at the exercise price per share set forth in
the Notice of Grant (the "Exercise Price"), subject to the terms and conditions
of the Plan, which is incorporated herein by reference. Subject to Section 14(b)
of the Plan, in the event of a conflict between the terms and conditions of the
Plan and the terms and conditions of this Option Agreement, the terms and
conditions of the Plan shall prevail.

     2. Exercise of Option.

          (a) Right to Exercise. This Option is exercisable during its term in
accordance with the Vesting Schedule set out in the Notice of Grant and the
applicable provisions of the Plan and this Option Agreement.

          (b) Method of Exercise. This Option is exercisable by delivery of an
exercise notice, in the form attached as Exhibit A (the "Exercise Notice"),
which shall state the election to exercise the Option, the number of Shares in
respect of which the Option is being exercised (the "Exercised Shares"), and
such other representations and agreements as may be required by the Company
pursuant to the provisions of the Plan. The Exercise Notice shall be completed
by the Optionee and delivered to Stock Option Administration. The Exercise
Notice shall be accompanied by payment of the aggregate Exercise Price as to all
Exercised Shares. This Option shall be deemed to be exercised upon receipt by
the Company of such fully executed Exercise Notice accompanied by such aggregate
Exercise Price.

          No Shares shall be issued pursuant to the exercise of this Option
unless such issuance and exercise complies with Applicable Laws. Assuming such
compliance, for income tax purposes the Exercised Shares shall be considered
transferred to the Optionee on the date the Option is exercised with respect to
such Exercised Shares.

     3. Method of Payment. Payment of the aggregate Exercise Price shall be by
any of the following, or a combination thereof, at the election of the Optionee:

          (a) cash;

          (b) check;

                                      -2-
<PAGE>   12

          (c) consideration received by the Company under a cashless exercise
program implemented by the Company in connection with the Plan; or

          (d) surrender of other Shares which (i) in the case of Shares acquired
upon exercise of an option, have been owned by the Optionee for more than six
(6) months on the date of surrender, and (ii) have a Fair Market Value on the
date of surrender equal to the aggregate Exercise Price of the Exercised Shares.

     4. Non-Transferability of Option. This Option may not be transferred in any
manner otherwise than by will or by the laws of descent or distribution and may
be exercised during the lifetime of Optionee only by the Optionee. The terms of
the Plan and this Option Agreement shall be binding upon the executors,
administrators, heirs, successors and assigns of the Optionee.

     5. Term of Option. This Option may be exercised only within the term set
out in the Notice of Grant, and may be exercised during such term only in
accordance with the Plan and the terms of this Option Agreement.

     6. Tax Consequences. Some of the federal tax consequences relating to this
Option, as of the date of this Option, are set forth below. THIS SUMMARY IS
NECESSARILY INCOMPLETE, AND THE TAX LAWS AND REGULATIONS ARE SUBJECT TO CHANGE.
THE OPTIONEE SHOULD CONSULT A TAX ADVISER BEFORE EXERCISING THIS OPTION OR
DISPOSING OF THE SHARES.

          (a) Exercising the Option. The Optionee may incur regular federal
income tax liability upon exercise of an NSO. The Optionee will be treated as
having received compensation income (taxable at ordinary income tax rates) equal
to the excess, if any, of the Fair Market Value of the Exercised Shares on the
date of exercise over their aggregate Exercise Price. If the Optionee is an
Employee or a former Employee, the Company will be required to withhold from his
or her compensation or collect from Optionee and pay to the applicable taxing
authorities an amount in cash equal to a percentage of this compensation income
at the time of exercise, and may refuse to honor the exercise and refuse to
deliver Shares if such withholding amounts are not delivered at the time of
exercise.

          (b) Disposition of Shares. If the Optionee holds NSO Shares for at
least one year, any gain realized on disposition of the Shares will be treated
as long-term capital gain for federal income tax purposes.

     7. Entire Agreement; Governing Law. The Plan is incorporated herein by
reference. The Plan and this Option Agreement constitute the entire agreement of
the parties with respect to the subject matter hereof and supersede in their
entirety all prior undertakings and agreements of the Company and Optionee with
respect to the subject matter hereof, and may not be modified adversely to the
Optionee's interest except by means of a writing signed by the Company and
Optionee. This agreement is governed by the internal substantive laws, but not
the choice of law rules, of California.

                                      -3-
<PAGE>   13

     8. NO GUARANTEE OF CONTINUED SERVICE. OPTIONEE ACKNOWLEDGES AND AGREES THAT
THE VESTING OF SHARES PURSUANT TO THE VESTING SCHEDULE HEREOF IS EARNED ONLY BY
CONTINUING AS A SERVICE PROVIDER AT THE WILL OF THE COMPANY (AND NOT THROUGH THE
ACT OF BEING HIRED, BEING GRANTED AN OPTION OR PURCHASING SHARES HEREUNDER).
OPTIONEE FURTHER ACKNOWLEDGES AND AGREES THAT THIS AGREEMENT, THE TRANSACTIONS
CONTEMPLATED HEREUNDER AND THE VESTING SCHEDULE SET FORTH HEREIN DO NOT
CONSTITUTE AN EXPRESS OR IMPLIED PROMISE OF CONTINUED ENGAGEMENT AS A SERVICE
PROVIDER FOR THE VESTING PERIOD, FOR ANY PERIOD, OR AT ALL, AND SHALL NOT
INTERFERE WITH OPTIONEE'S RIGHT OR THE COMPANY'S RIGHT TO TERMINATE OPTIONEE'S
RELATIONSHIP AS A SERVICE PROVIDER AT ANY TIME, WITH OR WITHOUT CAUSE.

     By your signature and the signature of the Company's representative below,
you and the Company agree that this Option is granted under and governed by the
terms and conditions of the Plan and this Option Agreement. Optionee has
reviewed the Plan and this Option Agreement in their entirety, has had an
opportunity to obtain the advice of counsel prior to executing this Option
Agreement and fully understands all provisions of the Plan and Option Agreement.
Optionee hereby agrees to accept as binding, conclusive and final all decisions
or interpretations of the Administrator upon any questions relating to the Plan
and Option Agreement. Optionee further agrees to notify the Company upon any
change in the residence address indicated below.

                                            BROCADE COMMUNICATIONS
OPTIONEE                                    SYSTEMS, INC.

-----------------------------------         ------------------------------------
Signature                                   By

-----------------------------------         ------------------------------------
Print                                       Title

-----------------------------------         ------------------------------------
Residence Address

-----------------------------------

                                      -4-
<PAGE>   14

                                    EXHIBIT A

                      BROCADE COMMUNICATIONS SYSTEMS, INC.

                       1999 NONSTATUTORY STOCK OPTION PLAN

                                 EXERCISE NOTICE

Brocade Communications Systems, Inc.
Attention: Stock Option Administration

     1. Exercise of Option. Effective as of today, ________________, _____, the
undersigned ("Purchaser") hereby elects to purchase ______________ shares (the
"Shares") of the Common Stock of Brocade Communications Systems, Inc. (the
"Company") under and pursuant to the 1999 Nonstatutory Stock Option Plan (the
"Plan") and the Stock Option Agreement dated, _________, ___ (the "Option
Agreement"). The purchase price for the Shares shall be $___, as required by the
Option Agreement.

     2. Delivery of Payment. Purchaser herewith delivers to the Company the full
purchase price for the Shares.

     3. Representations of Purchaser. Purchaser acknowledges that Purchaser has
received, read and understood the Plan and the Option Agreement and agrees to
abide by and be bound by their terms and conditions.

     4. Rights as Shareholder. Until the issuance (as evidenced by the
appropriate entry on the books of the Company or of a duly authorized transfer
agent of the Company) of the Shares, no right to vote or receive dividends or
any other rights as a shareholder shall exist with respect to the Optioned
Stock, notwithstanding the exercise of the Option. The Shares so acquired shall
be issued to the Optionee as soon as practicable after exercise of the Option.
No adjustment will be made for a dividend or other right for which the record
date is prior to the date of issuance, except as provided in Section 12 of the
Plan.

     5. Tax Consultation. Purchaser understands that Purchaser may suffer
adverse tax consequences as a result of Purchaser's purchase or disposition of
the Shares. Purchaser represents that Purchaser has consulted with any tax
consultants Purchaser deems advisable in connection with the purchase or
disposition of the Shares and that Purchaser is not relying on the Company for
any tax advice.

<PAGE>   15

     6. Entire Agreement; Governing Law. The Plan and Option Agreement are
incorporated herein by reference. This Agreement, the Plan and the Option
Agreement constitute the entire agreement of the parties with respect to the
subject matter hereof and supersede in their entirety all prior undertakings and
agreements of the Company and Purchaser with respect to the subject matter
hereof, and may not be modified adversely to the Purchaser's interest except by
means of a writing signed by the Company and Purchaser. This agreement is
governed by the internal substantive laws, but not the choice of law rules, of
California.

Submitted by:                               Accepted by:

                                            BROCADE COMMUNICATIONS
PURCHASER                                   SYSTEMS, INC.

-----------------------------------         ------------------------------------
Signature                                   By

-----------------------------------         ------------------------------------
Print Name                                  Title

-----------------------------------         ------------------------------------
                                            Date Received

Address:
        ---------------------------

        ---------------------------

                                      -2-

Source: [{"source": "alea-institute/alea-institute/kl3m-data-edgar-agreements/train-00000-of-00352.parquet"}, [{"source": "alea-institute/alea-institute/kl3m-data-edgar-agreements/train-00000-of-00352.parquet"}]]