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                                                                    EXHIBIT 10.3

                       AVISTAR COMMUNICATIONS CORPORATION

                            2000 DIRECTOR OPTION PLAN

                        (AS AMENDED EFFECTIVE JUNE 2003)

         1.       Purposes of the Plan. The purposes of this 2000 Director
Option Plan are to attract and retain the best available personnel for service
as Outside Directors (as defined herein) of the Company, to provide additional
incentive to the Outside Directors of the Company to serve as Directors, and to
encourage their continued service on the Board.

                  All options granted hereunder shall be nonstatutory stock
options.

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

                  (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 Avistar Communications
Corporation, a Delaware corporation.

                  (e)      "Director" shall mean a member of the Board.

                  (f)      "Disability" shall mean total and permanent
disability as defined in section 22(e)(3) of the Code.

                  (g)      "Employee" shall mean any person, including officers
and Directors, 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" shall mean the Securities Exchange Act
of 1934, as amended.

                  (i)      "Fair Market Value" shall mean, 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

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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 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 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)      "Inside Director" shall mean a Director who is an
Employee.

                  (k)      "Option" shall mean a stock option granted pursuant
to the Plan.

                  (l)      "Optioned Stock" shall mean the Common Stock subject
to an Option.

                  (m)      "Optionee" shall mean a Director who holds an Option.

                  (n)      "Outside Director" shall mean a Director who is not
an Employee.

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

                  (p)      "Plan" shall mean this 2000 Director Option Plan.

                  (q)      "Share" shall mean a share of the Common Stock, as
adjusted in accordance with Section 10 of the Plan.

                  (r)      "Subsidiary" shall mean a "subsidiary corporation,"
whether now or hereafter existing, as defined in Section 424(f) of the Internal
Revenue Code of 1986.

         3.       Stock Subject to the Plan. Subject to the provisions of
Section 10 of the Plan, the maximum aggregate number of Shares which may be
optioned and sold under the Plan is 464,000 Shares (the "Pool") (the Shares may
be authorized, but unissued, or reacquired Common Stock), together with an
annual increase to the number of Shares reserved thereunder on the first day of
the Company's fiscal year, beginning with January 1, 2004, equal to the lesser
of (i) 175,000 Shares, (ii) 1.0% of the outstanding Shares of Common Stock on
the last day of each prior fiscal year or (iii) such amount as determined by the
Board.

                  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). Shares that have actually been issued under the Plan shall not be
returned to the Plan and shall not become available for future distribution
under the Plan.

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         4.       Administration and Grants of Options under the Plan.

                  (a)      Procedure for Grants. All grants of Options to
Outside Directors under this Plan shall be automatic and nondiscretionary 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.

                           (ii)     Each Outside Director shall be automatically
granted a one-time Option to purchase 50,000 Shares (the "First Option") on the
date on which such person first becomes an Outside Director, whether through
election by the stockholders of the Company or appointment by the Board to fill
a vacancy; provided, however, that an Inside Director who ceases to be an Inside
Director but who remains a Director shall not receive a First Option. The First
Option for an Outside Director who has not previously received a stock option
grant from the Company shall be for 50,000 Shares.

                           (iii)    Each Outside Director shall subsequently be
automatically granted an Option to purchase Shares (a "Subsequent Option") on
the date of the next meeting of the Board following the Annual Meeting of
Stockholders in each year commencing with the 2001 Annual Meeting of
Stockholders provided he or she is then an Outside Director and if as of such
date, he or she shall have served on the Board for at least the preceding six
(6) months. The Subsequent Option shall be for 25,000 Shares.

                           (iv)     Each Outside Director who is a member of the
Audit Committee of the Board of Directors shall also be automatically granted an
additional Option to purchase Shares (a "Subsequent Audit Committee Option") on
the date of the next meeting of the Board following the Annual Meeting of
Stockholders in each year commencing with the 2003 Annual Meeting of
Stockholders provided he or she is then a member of the Audit Committee of the
Board of Directors. The Subsequent Audit Committee Option shall be for 10,000
Shares for the Chairman of the Audit Committee and 5,000 Shares for each other
member of the Audit Committee.

                           (v)      Each Outside Director serving on the Board
as of June 12, 2001 shall be automatically granted an Option to purchase 60,000
Shares at an exercise price equal to 100% of the fair market value on such date
(a "One-Time Option"), subject to stockholder approval at the Company's 2001
Annual Meeting of Stockholders.

                           (vi)     Notwithstanding the provisions of
subsections (ii), (iii), (iv) and (v) hereof, any exercise of an Option granted
before the Company has obtained stockholder approval of the Plan in accordance
with Section 16 hereof shall be conditioned upon obtaining such stockholder
approval of the Plan in accordance with Section 16 hereof.

                           (vii)    The terms of a First Option granted
hereunder shall be as follows:

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

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                                    (B)      the First Option shall be
exercisable only while the Outside Director remains a Director of the Company,
except as set forth in Sections 8 and 10 hereof.

                                    (C)      the exercise price per Share shall
be 100% of the Fair Market Value per Share on the date of grant of the First
Option provided, however, that in the case of a First Option granted on the
effective date of the Company's initial public offering pursuant to a
registration statement filed with the Securities and Exchange Commission, the
exercise price per share shall be the initial public offering price per share.

                                    (D)      subject to Section 10 hereof, the
First Option shall become exercisable as to 1/4 of the Shares subject to the
First Option on the first, second, third and fourth anniversaries of the date of
grant, so that the First Option shall be fully exercisable four years after its
date of grant, provided that the Optionee continues to serve as a Director on
such dates.

                           (viii)   The terms of a Subsequent Option granted
hereunder shall be as follows:

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

                                    (B)      the Subsequent Option shall be
exercisable only while the Outside Director remains a Director of the Company,
except as set forth in Sections 8 and 10 hereof.

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

                                    (D)      subject to Section 10 hereof, the
Subsequent Option shall become exercisable cumulatively with respect to 1/4th of
the Subsequent Option at the end of each year after the date of grant, so that
the Subsequent Option shall be fully exercisable four years after its date of
grant, provided that the Optionee continues to serve as a Director on such
dates.

                           (ix)     The terms of a One-Time Option granted
hereunder shall be as follows:

                                    (A)      the term of the One-Time Option
shall be ten (10) years.

                                    (B)      the One-Time Option shall be
exercisable only while the Outside Director remains a Director of the Company,
except as set forth in Sections 8 and 10 hereof.

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

                                    (D)      subject to Section 10 hereof, the
One-Time Option shall become exercisable cumulatively with respect to 1/4th of
the One-Time Option at the end of each year after the date of grant, so that the
One-Time Option shall be fully exercisable four years after its date of grant,
provided that the Optionee continues to serve as a Director on such dates.

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                           (x)      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 under Options to exceed the Pool, then
the remaining Shares available for Option grant shall be granted under Options
to the Outside Directors on a pro rata basis. 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 Board or the stockholders to increase the number
of Shares which may be issued under the Plan or through cancellation or
expiration of Options previously granted hereunder.

         5.       Eligibility. Options may be granted only to Outside Directors.
All Options shall be automatically granted in accordance with the terms set
forth in Section 4 hereof.

                  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 the Director's relationship with the
Company at any time.

         6.       Term of Plan. The Plan shall become effective upon the earlier
to occur of its adoption by the Board or its approval by the stockholders of the
Company as described in Section 16 of the Plan; provided, however, the Plan
shall not become effective until the effective date of the Company's initial
public offering pursuant to a registration statement filed with the Securities
and Exchange Commission. It shall continue in effect for a term of ten (10)
years unless sooner terminated under Section 11 of the Plan.

         7.       Form of Consideration. The consideration to be paid for the
Shares to be issued upon exercise of an Option, including the method of payment,
shall consist of (i) cash, (ii) check, (iii) other shares which (x) 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 (y) 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, (iv) consideration
received by the Company under a cashless exercise program implemented by the
Company in connection with the Plan, or (v) any combination of the foregoing
methods of payment.

         8.       Exercise of Option.

                  (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 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

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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
shall 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.
Subject to Section 10 hereof, in the event an Optionee's status as a Director
terminates (other than upon the Optionee's death or Disability), the Optionee
may exercise his or her Option, but only within three (3) months following the
date of such termination, and only to the extent that the Optionee was entitled
to exercise it on the date of such termination (but in no event later than the
expiration of its ten (10) year term). To the extent that the Optionee was not
entitled to exercise an Option on 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
status as a Director terminates as a result of Disability, the Optionee may
exercise his or her Option, but only within twelve (12) months following the
date of such termination, and only to the extent that the Optionee was entitled
to exercise it on the date of such termination (but in no event later than the
expiration of its ten (10) year term). To the extent that the Optionee was not
entitled to exercise an Option on 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, 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 twelve
(12) months following the date of death, and only to the extent that the
Optionee was entitled to exercise it on the date of death (but in no event later
than the expiration of its ten (10) year term). To the extent that the Optionee
was not entitled to exercise an Option on 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, 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.

         10.      Adjustments upon Changes in Capitalization, Dissolution,
Merger or Asset Sale.

                  (a)      Changes in Capitalization. Subject to any required
action by the stockholders of the Company, the number of Shares covered by each
outstanding Option, the number of Shares

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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 covered
by each such outstanding Option, and the number of Shares issuable pursuant to
the automatic grant provisions of Section 4 hereof shall be proportionately
adjusted for any increase or decrease in the number of issued Shares 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 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." 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 subject to an Option.

                  (b)      Dissolution or Liquidation. In the event of the
proposed dissolution or liquidation of the Company, to the extent that an Option
has not been previously exercised, it shall 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, outstanding Options may be assumed or equivalent options
may be substituted by the successor corporation or a Parent or Subsidiary
thereof (the "Successor Corporation"). If an Option is assumed or substituted
for, the Option or equivalent option shall continue to be exercisable as
provided in Section 4 hereof for so long as the Optionee serves as a Director or
a director of the Successor Corporation. Following such assumption or
substitution, if the Optionee's status as a Director or director of the
Successor Corporation, as applicable, is terminated other than upon a voluntary
resignation by the Optionee, the Option or option shall become fully
exercisable, including as to Shares for which it would not otherwise be
exercisable. Thereafter, the Option or option shall remain exercisable in
accordance with Sections 8(b) through (d) above.

         If the Successor Corporation does not assume an outstanding Option or
substitute for it an equivalent option, the Option shall become fully vested and
exercisable, including as to Shares for which it would not otherwise be
exercisable. In such event the Board shall notify the Optionee that the Option
shall be fully exercisable for a period of fifteen (15) days from the date of
such notice, and upon the expiration of such period the Option shall terminate.

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         For the purposes of this Section 10(c), an Option shall be considered
assumed if, following the merger or sale of assets, the Option confers the right
to purchase or receive, for each Share of Optioned Stock subject to the Option
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).
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
subject to the Option, 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.

         11.      Amendment and Termination of the Plan.

                  (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 any applicable
law, regulation or stock exchange rule, 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 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
hereof.

         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
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.

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                  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, 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.

         16.      Stockholder Approval. The Plan shall be subject to approval by
the stockholders of the Company within twelve (12) months after the date the
Plan is adopted. Such stockholder approval shall be obtained in the degree and
manner required under applicable state and federal law and any stock exchange
rules.

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