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                                                                   EXHIBIT 10.10


                                 XIRCOM, INC.
                        1992 DIRECTOR STOCK OPTION PLAN

                  As amended and restated on January 22, 1999


     1.   Purpose of the Plan.  The purpose of this 1992 Director Stock Option
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Plan is to attract and retain the best available personnel to serve as Outside
Directors of the Company.

          All options granted hereunder shall be "non-statutory stock options".

     2.   Definitions.  As used herein, the following definitions shall apply:
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          (a) "Board" means the Board of Directors of the Company.
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          (b) "Code" means the Internal Revenue Code of 1986, as amended.
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          (c) "Common Stock" means the Common Stock of the Company.
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          (d) "Company" means Xircom, Inc., a California corporation.
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          (e) "Continuous Status as a Director" means the absence of any
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interruption or termination of service as a Director.

          (f) "Director" means a member of the Board.
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          (g) "Employee" means any person, including officers and Directors,
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employed by the Company or any Parent or Subsidiary of the Company.  The payment
of a Director's fee by the Company shall not be sufficient in and of itself to
constitute "employment" by the Company.

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

          (i) "Fair Market Value" means, as of any date, the value of Common
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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 National Market
System of the National Association of Securities Dealers, Inc. Automated
Quotation ("NASDAQ") System, the Fair Market Value of a Share of Common Stock
shall be the closing sales price for such stock (or the closing bid, if no sales
were reported) as quoted on such system or exchange (or the exchange with the
greatest volume of trading in 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 Board deems reliable;

             (ii) If the Common Stock is quoted on the NASDAQ System (but not on
the National Market System thereof) or 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 
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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.

          (j) "Option" means a stock option granted pursuant to the Plan.
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          (k) "Optioned Stock" means the Common Stock subject to an Option.
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          (l) "Optionee"  means an Outside Director who receives an Option.
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          (m) "Outside Director" means a Director who is not an Employee.
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          (n) "Parent" means a "parent corporation", whether now or hereafter
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existing, as defined in Section 424(e) of the Code.

          (o) "Plan" means this 1992 Director Stock Option Plan.
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          (p) "Share" means a share of the Common Stock, as adjusted in
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accordance with Section 10 of the Plan.

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

     3.   Stock Subject to the Plan.  Subject to the provisions of Section 10 of
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the Plan, the maximum aggregate number of Shares which may be optioned and sold
under the Plan is 725,000 Shares (the "Pool") of Common Stock.  The Shares may
be authorized but unissued, or reacquired Common Stock.

          If an Option should expire or become unexercisable for any reason
without having been exercised in full, the unpurchased Shares which were subject
thereto shall, unless the Plan shall have been terminated, become available for
future grant under the Plan.

     4.   Administration of and Grants of Options under the Plan.
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          (a) Administrator.  Except as otherwise required herein, the Plan
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shall be administered by the Board.

          (b) Procedure for Grants.  The provisions set forth in this Section
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4(b) shall not be amended more than once every six months, other than to comply
with changes in the Code, the Employee Retirement Income Security Act of 1974,
as amended, or the rules thereunder.  All grants of Options hereunder shall be
automatic and non-discretionary and shall be made strictly in accordance with
the following provisions:

             (i) No person shall have any discretion to select which Outside
Directors shall be granted Options or to determine the number of Shares to be
covered by Options granted to Outside Directors.

             (ii) On July 1, 1992 and on each July 1 thereafter during the term
of this Plan, each Outside Director who shall have been an Outside Director for
at least six (6) months as of such date shall automatically receive an Option to
purchase 10,000 Shares (an "Annual Grant"). In addition, each new Outside
Director who shall first join the Board on or after May 1, 1992 shall
automatically be granted an Option to purchase 40,000 Shares upon the date on
which such person first becomes an Outside Director, whether through election by
the shareholders of the Company, appointment by the Board to fill a vacancy, or
termination of employment by the Company while remaining as a Director (a "One-
Time Grant").
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             (iii)  The terms of each Option granted hereunder shall be as
follows:

                    (A) the term of the Option shall be ten (10) years;

                    (B) the Option shall be exercisable only while the Outside
Director remains a Director of the Company, except as set forth in Section 8
hereof;

                    (C) the exercise price per Share shall be 100% of the Fair
Market Value per Share on the date of grant of the Option;

                    (D) each One-Time Grant shall become exercisable in
installments cumulatively as to 25% of the Optioned Stock on each anniversary of
the date of grant, so that 100% of the Optioned Stock granted under any One-Time
Grant shall be exercisable four years after the date of grant of the Option,
assuming Continuous Status as a Director; and,

                    (E) each Annual Grant shall become exercisable in its
entirety on the fourth anniversary of the date of grant of the Option, assuming
Continuous Status as a Director.

             (iv) In the event that any Option granted under the Plan would
cause the number of Shares subject to outstanding Options plus the number of
Shares previously purchased upon exercise of Options to exceed the Pool, then
each such automatic grant shall be for that number of Shares determined by
dividing the total number of Shares remaining available for grant by the number
of Outside Directors entitled to receive Options on the grant date. No further
grants shall be made until such time, if any, as additional Shares become
available for grant under the Plan through action of the shareholders to
increase the number of Shares which may be issued under the Plan or through
cancellation or expiration of Options previously granted hereunder.

          (c) Powers of the Board.  Subject to the provisions and restrictions
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of the Plan, the Board shall have the authority, in its discretion:  (i) to
determine, upon review of relevant information and in accordance with Section
2(i) of the Plan, the Fair Market Value of the Common Stock; (ii) to interpret
the Plan; (iii) to prescribe, amend and rescind rules and regulations relating
to the Plan; (iv) to authorize any person to execute on behalf of the Company
any instrument required to effectuate the grant of an Option previously granted
hereunder; and (v) to make all other determinations deemed necessary or
advisable for the administration of the Plan.

          (d) Effect of Board's Decision.  All decisions, determinations and
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interpretations of the Board shall be final.

     5.   Eligibility.  Options may be granted only to Outside Directors.  All
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Options shall be automatically granted in accordance with the terms set forth in
Section 4(b) hereof.  An Outside Director who has been granted an Option may, if
he or she is otherwise eligible, be granted an additional Option or Options in
accordance with such provisions.

          The Plan shall not confer upon any Optionee any right with respect to
continuation of service as a Director or nomination to serve as a Director, nor
shall it interfere in any way with any rights which the Director or the Company
may have to terminate his or her directorship at any time.

     6.   Term of Plan.  The Plan shall become effective upon the earlier to
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occur of its adoption by the Board or its approval by the stockholders of the
Company as described in Section 16 of the Plan.  It shall continue in effect
until December 31, 2002, unless sooner terminated under Section 11 of the Plan.
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     7.   Consideration.  The consideration to be paid for the Shares to be
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issued upon exercise of an Option, including the method of payment, shall be
determined by the Board and may consist entirely of (i) cash, (ii) check, (iii)
promissory note, (iv) other shares which 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 and which, in the case of Shares acquired upon
exercise of an option, have been owned by the Optionee for more than 12 months
on the date of surrender, (v) delivery of a properly executed exercise notice
together with irrevocable instructions to a broker to promptly deliver to the
Company the amount of sale or loan proceeds required to pay the exercise price,
(vi) delivery of an irrevocable subscription agreement for the Shares which
irrevocably obligates the Optionee to take and pay for the Shares not more than
12 months after the date of delivery of the subscription agreement, (vii) any
combination of the foregoing methods of payment, or (viii) such other
consideration and method of payment for the issuance of Shares to the extent
permitted under applicable law.

     8.   Exercise of Option.
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          (a) Procedure for Exercise; Rights as a Stockholder. Any Option
              -----------------------------------------------            
granted hereunder shall be exercisable at such times as are set forth in Section
4(b) hereof; provided, however, that no Options shall be exercisable until
stockholder approval of the Plan in accordance with Section 16 hereof has been
obtained.

          An Option may not be exercised for a fraction of a Share.

          An Option shall be deemed to be exercised when written notice of such
exercise has been given to the Company in accordance with the terms of the
Option by the person entitled to exercise the Option and full payment for the
Shares with respect to which the Option is exercised has been received by the
Company.  Full payment may consist of any consideration and method of payment
allowable under Section 7 of the Plan.  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 stock certificate evidencing such Shares, no right
to vote or receive dividends or any other rights as a stockholder shall exist
with respect to the Optioned Stock, notwithstanding the exercise of the Option.
A share certificate for the number of 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 the stock certificate is issued, except as provided in Section 10 of
the Plan.

          Exercise of an Option in any manner shall result in a decrease in the
number of Shares which thereafter may be 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 Continuous Status as a Director.  In the event an
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Optionee's Continuous Status as a Director terminates (other than upon the
Optionee's death or total and permanent disability (as defined in Section
22(e)(3) of the Code)), the Optionee may exercise his or her Option, but only
within 90 days from the date of such termination, and only to the extent that
the Optionee was entitled to exercise it at the date of such termination (but in
no event later than the expiration of its five-year term).  To the extent that
the Optionee was not entitled to exercise an Option at the date of such
termination, and to the extent that the Optionee does not exercise such Option
(to the extent otherwise so entitled) within the time specified herein, the
Option shall terminate.

          (c) Disability of Optionee.  In the event Optionee's Continuous Status
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as a Director terminates as a result of total and permanent disability (as
defined in Section 22(e)(3) of the Code), the Optionee may exercise his or her
Option, but only 
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within six months from the date of such termination, and only to the extent that
the Optionee was entitled to exercise it at the date of such termination (but in
no event later than the expiration of its five-year term). To the extent that
the Optionee was not entitled to exercise an Option at the date of termination,
or if he or she does not exercise such Option (to the extent otherwise so
entitled) within the time specified herein, the Option shall terminate.

          (d) Death of Optionee.  In the event of an Optionee's death while a
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Director or within 90 days after ceasing to be a Director, the Optionee's estate
or a person who acquired the right to exercise the Option by bequest or
inheritance may exercise the Option, but only within one year following the date
of death, and only to the extent that the Optionee was entitled to exercise it
at the date of death (but in no event later than the expiration of its five-year
term).  To the extent that the Optionee was not entitled to exercise an Option
at the date of death, and to the extent that the Optionee's estate or a person
who acquired the right to exercise such Option does not exercise such Option (to
the extent otherwise so entitled) within the time specified herein, the Option
shall terminate.

     9.   Non-Transferability of Options.  The Option may not be sold, pledged,
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assigned, hypothecated, transferred or disposed of in any manner other than by
will, by the laws of descent or distribution or pursuant to a qualified domestic
relations order, and may be exercised, during the lifetime of the Optionee, only
by the Optionee or a permitted transferee.

     10.  Adjustments.
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          (a) Changes in Capitalization.  In the event that the stock of the
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Company is changed by reason of any stock split, reverse stock split,
recapitalization, or other change in the capital structure of the Company, or
converted into or exchanged for other securities as a result of any merger,
consolidation or reorganization, or in the event that the outstanding number of
shares of stock of the Company is increased through payment of a stock dividend,
appropriate proportionate adjustments shall be made in the number and class of
shares of stock subject to the Plan, the number and class of shares subject to
any Option outstanding under the Plan, and the exercise price of any such
outstanding Option; provided, however, that the Company shall not be required to
issue fractional shares as a result of any such adjustment.  Any such adjustment
shall be made upon approval by the Board, whose determination shall be
conclusive.  If there is any other change in the number or type of the
outstanding shares of stock of the Company, or of any other security into which
such stock shall have been changed or for which it shall have been exchanged,
and if the Board in its sole discretion determines that such change equitably
requires an adjustment in the Options then outstanding under the Plan, such
adjustment shall be made in accordance with the determination of the Board.  No
adjustments shall be required by reason of the issuance or sale by the Company
for cash or other consideration of additional shares of its stock or securities
convertible into or exchangeable for shares of its stock.

          (b) Corporate Transactions.  New Options (substantially equivalent to
              ----------------------                                           
the Options) may be substituted for the Options granted under the Plan, or the
Company's duties as to Options outstanding under the Plan may be assumed, by an
employer corporation other than the Company or by a parent or subsidiary of such
employer corporation, in connection with any merger, consolidation, acquisition
of assets or stock, separation, reorganization, liquidation or like occurrence
in which the Company is involved; provided, however, in the event such employer
corporation or parent or subsidiary of such employer corporation does not assume
the Options granted hereunder or substitute for such Options substantially
equivalent options, or if the Board determines, in its sole discretion, that
Options outstanding under the Plan should not then continue to be outstanding,
the Options granted hereunder shall terminate and thereupon become null and void
(i) upon dissolution or liquidation of the Company, acquisition, separation, or
similar occurrence, or (ii) upon any merger, 
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consolidation or similar occurrence, where the Company will not be a surviving
corporation, provided, however, that each Optionee shall be given notice of such
dissolution, liquidation, merger, consolidation, acquisition, separation or
similar occurrence and shall have the right, at any time prior to, but
contingent upon the consummation of such transaction, to exercise (x) any
unexpired Options granted hereunder to the extent they are then exercisable, and
(y) in the case of a merger, consolidation or similar occurrence where the
Company is not the surviving corporation, those Options which are not then
otherwise exercisable; provided, further, that such exercise right shall not in
any event expire less than 30 days after the date notice of such transaction is
sent to the Optionee.

     11.  Amendment and Termination of the Plan.
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          (a) Amendment and Termination.  The Board may at any time amend,
              -------------------------                                   
alter, suspend or discontinue the Plan, but no amendment, alteration, suspension
or discontinuation shall be made which would impair the rights of any Optionee
under any grant theretofore made, without his or her consent.  In addition, to
the extent necessary and desirable to comply with Rule 16b-3 under the Exchange
Act (or any other applicable law or regulation), the Company shall obtain
stockholder approval of any Plan amendment in such a manner and to such a degree
as required.

          (b) Effect of Amendment or Termination.  Any such amendment or
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termination of the Plan shall not affect Options already granted and such
Options shall remain in full force and effect as if this Plan had not been
amended or terminated.

     12.  Time of Granting Options.  The date of grant of an Option shall, for
          ------------------------                                            
all purposes, be the date determined in accordance with Section 4(b) hereof.
Notice of the determination shall be given to each Outside Director to whom an
Option is so granted within a reasonable time after the date of such grant.

     13.  Conditions Upon Issuance of Shares.  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 pursuant thereto shall comply with all
relevant provisions of law, including, without limitation, the Securities Act of
1933, as amended, the Exchange Act, the rules and regulations promulgated
thereunder, state securities laws and the requirements of any stock exchange or
market system 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 relevant provisions of law.

          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.

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

     15.  Option Agreement.  Options shall be evidenced by written option
          ----------------                                               
agreements in such form as the Board shall approve.
<PAGE>
 
     16.  Stockholder Approval.  Continuance of the Plan shall be subject to
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approval by the stockholders of the Company at or prior to the first annual
meeting of stockholders held subsequent to the first granting of an Option
hereunder. Such stockholder approval shall be obtained in the degree and manner
required under applicable state and federal law.