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                                                                     EXHIBIT 4.3


                                NETSILICON, INC.
                              AMENDED AND RESTATED
               1998 INCENTIVE AND NON-QUALIFIED STOCK OPTION PLAN


1.   PURPOSES OF PLAN. The purposes of the NETsilicon, Inc. 1998 Amended and
Restated Incentive and Non-Qualified Stock Option Plan (hereinafter referred to
as the "Plan") are to provide to employees and consultants of NETsilicon, Inc.
(hereinafter referred to as the "Corporation"), as well as employees subsidiary
or parent corporations which may currently exist or be formed or acquired in the
future, an opportunity for investment in the Corporation's common stock
(hereinafter referred to as the "Shares"), as an inducement for such individuals
to remain with the Corporation, and to encourage them to increase their efforts
to make the Corporation's business more successful.

2.   EFFECTIVE DATE AND TERMINATION OF PLAN. The effective date of the Plan is
August 24, 1998, the date on which the Plan was adopted by the Board of
Directors of the Corporation. The Plan shall terminate on, and no option shall
be granted hereunder, after August 24, 2008; provided, however, that the Board
of Directors may at any time prior to that date terminate the Plan; and provided
further that any option granted hereunder prior to the termination of the Plan
shall remain exercisable in accordance with its terms as then in effect.

3.   ADMINISTRATION OF PLAN. The Plan shall be administered by the Board of
Directors of the Corporation. The Board of Directors may, however, to the extent
permissible under the Corporation's Articles of Organization, By-laws and
applicable law, delegate any of its functions under this Plan to a committee of
the Board of Directors or any other committee. Wherever in this Plan the term
"Board of Directors" is used it shall be construed to mean such committee to the
extent that the Board of Directors may have delegated any of its functions to
said committee and only to the extent of any such delegation. The acts of a
majority of the members present at any meeting of the Board of Directors at
which a quorum is present, or acts approved in writing by a majority of the
entire Board, shall be the acts of the Board of Directors for purposes of the
Plan.

4.   ELIGIBILITY AND GRANT OF OPTIONS. Subject to the provisions of the Plan,
the Board of Directors shall (i) authorize the granting of incentive stock
options, non-qualified stock options or a combination of incentive stock options
and non-qualified stock options (hereinafter collectively referred to as
"options" unless otherwise stated); (ii) determine and designate from time to
time those employees (from the group consisting of all employees of the Company)
and consultants to whom options are to be granted and the number of Shares to be
optioned to each employee and consultant; (iii) determine the number of Shares
subject to each option; and (iv) determine the time or times when and the manner
in which each option shall be exercisable and the duration of the exercise
period. In determining the eligibility of an individual to receive an option, as
well as in determining the number of Shares to be optioned to any individual,
the Board of Directors shall consider the position and responsibilities of the
employee or consultant, the nature and value to the Corporation, parent or
subsidiary of his services and accomplishments, his present and potential
contribution to the success of the Corporation, parent or subsidiary, and such
other factors as the Board may deem relevant. To be eligible to receive an
incentive stock option or non-qualified stock option an individual must be an
employee of the Corporation, parent

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or subsidiary. A Director shall abstain from voting on the grant of any options
to himself, his spouse, his children, grandchildren and parents. The grant of
each option shall be confirmed by a Stock Option Agreement (in the form
prescribed by the Board of Directors) which shall be executed by the Corporation
and the optionee as promptly as practicable after such grant. More than one
option may be granted to an individual.

     (a) Incentive stock options shall be those options which satisfy the
     requirements of Section 422 of the Internal Revenue Code of 1986, as
     amended and which the Board of Directors has specifically identified as
     incentive stock options in the Stock Option Agreement executed by the
     Corporation and the optionee. In the case of incentive stock options, the
     aggregate fair market value, determined at the time incentive stock options
     are granted, of the stock with respect to which the incentive stock options
     are exercisable for the first time by such individual during any calendar
     year (under all such plans the Corporation may adopt) shall not exceed one
     hundred thousand dollars ($100,000.00). In the event that an incentive
     stock option granted pursuant to the terms of this Plan is granted to an
     employee who, prior to the grant, holds more than ten percent (10%) of the
     total combined voting power of all classes of stock of the Corporation, its
     parent or a subsidiary ("10% shareholder") the option price under such
     grant shall be at least one hundred ten percent (110%) of the fair market
     value, and such option, by its terms, shall not be exercisable more than
     five (5) years from the date of grant.

     (b) Nothing in the Plan or in any option granted pursuant to the Plan shall
     confer on any individual any right to continue in the employ of the
     Corporation or any parent or subsidiary or interfere in any way with the
     right of the Corporation to terminate his employment at any time.

5.   NUMBER OF SHARES SUBJECT TO OPTIONS. The Board of Directors, prior to the
time options under the Plan become exercisable, shall reserve for the purposes
of the Plan a total of six million (6,000,000) Shares, which Shares may be
either authorized and unissued Shares, or previously issued Shares held in the
treasury of the Corporation, or both. Shares as to which an option granted under
the Plan shall remain unexercised at the expiration or termination thereof, and
Shares subject to options which are cancelled, may be the subject of the grant
of further options. Shares reserved pursuant to this paragraph may be adjusted
to reflect changes in the Corporation's capital structure as discussed in
paragraph 19 hereof.

6.   OPTION PRICE. The option price per Share shall be determined in each case
by the Board of Directors and shall not be less than one hundred percent (100%)
(one hundred ten percent (110%) in the case of an incentive stock option granted
to a ten percent (10%) Shareholder) of the fair market value thereof as
determined by the Board by any reasonable method using market quotations on the
date the option is granted.


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7.   PERIOD OF OPTION AND WHEN EXERCISABLE. No option may be granted under this
Plan whose exercise date is later than ten (10) years after the date of grant or
five (5) years after the date of grant in the case of an incentive stock option
granted to a ten percent (10%) Shareholder. Generally, an option may be
exercised only by the optionee and subject to the rules set forth below only if,
at all times during the period beginning on the date of the granting of such
option and ending with the date of exercise of such option, the optionee is an
employee or consultant of the Corporation, its parent or a subsidiary.

     (a) Except as otherwise provided herein, in the case of an employee who
     terminates employment, incentive stock options which are vested but
     unexercised as of the date of termination of employment must be exercised
     within three (3) months of termination. In the case of an employee who is
     discharged for cause, as determined in the sole discretion of the Board of
     Directors, all previously vested but unexercised options shall be forfeited
     immediately.

     (b) In the case of an employee who dies during the three (3) month period
     discussed in (a) above, options which are vested but unexercised as of the
     date of termination of employment must be exercised within twelve (12)
     months of death.

     (c) Options which are vested but unexercised as of the date of termination
     of employment due to death, must be exercised within twelve (12) months
     after the death of an optionee.

     (d) In the event that the employee becomes disabled as defined in Section
     22(e) (3) of the Internal Revenue code of 1986, as amended, options which
     are vested but unexercised as of the date of termination of employment due
     to disability must be exercised within twelve (12) months following the
     date of termination of the optionee's said employment.

     (e) In the event an optionee's employment is terminated for any reason
     (including but not limited to, voluntary or involuntary termination or
     termination resulting from the death or disability of the optionee), all
     unvested options shall be immediately forfeited.

     Notwithstanding the foregoing, options may not be exercised after the
original five (5) or ten (10) year term, Options may be exercised on behalf of
the estate of a former employee by the person or persons entitled to do so under
the optionee's will or, if the optionee shall have failed to make testamentary
disposition of such option or shall have died in testate, by the optionee's
legal representative or representatives. Such person, persons, representative,
or representatives are hereinafter referred to as the "Successors of an
Optionee."


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8.   VESTING. Options granted to a participant shall be exercisable in
accordance with the following schedule unless the Board of Directors otherwise
specifies at the time of grant:


                                             Cumulative Percentage of Aggregate
                                              Number of Shares of Stock Covered
Exercise Period                              by an Option Which may be Exercised
---------------                              -----------------------------------

Beginning on the one year anniversary
date from date of grant                                     25%

Beginning on the second anniversary
date from date of grant                                     50%*

Beginning on the third anniversary
date from date of grant                                     75%*

Beginning on the fourth anniversary
date from date of grant                                    100%*

     * less the number of Shares, if any, previously purchased under the option.
     Non-vested options shall be immediately forfeited upon the termination of
     employment for any reason. Vested options shall be forfeited upon the
     termination of employment as provided in paragraph 7 hereof.

Notwithstanding the foregoing, the Board of Directors or its designees shall
have the right to grant any options with any vesting schedules including those
which are immediately exercisable under the Plan.

9.   EXERCISE OF OPTIONS. Subject to Plan restrictions and vesting, an option
may be exercised, and payment in full of the option price made, by an optionee
only by written notice (in the form prescribed by the Board of Directors) to the
Corporation specifying the number of Shares to be so purchased. Such notice
shall state that the option price will be paid in full in cash (which in the
discretion of the Board of Directors may be obtained through a loan from the
Corporation or from a third party and guaranteed by the Corporation) or other
property, in the discretion of the Corporation. If the Corporation accepts a
request to pay in stock of the Corporation in satisfaction of the exercise
price, the fair market value of said stock shall at least equal the option
price, and, in the case of incentive stock options, prior to such acceptance the
Corporation must be furnished with evidence that the acquisition of said stock
and its transfer in payment of the option price satisfies the requirements of
Section 422 of the Internal Revenue Code of 1986, as amended and other
applicable law. As soon as practicable after receipt by the Corporation of such
notice and of payment in full of the option price of all the Shares with respect
to which an option has been exercised, a certificate or certificates
representing such Shares shall be registered (subject to the provisions of
paragraph 16 hereof) in the name of the optionee or the Successors of an
Optionee as defined under this Plan and delivered to the optionee or to the
Successors of an Optionee.


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10.  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 7
hereof for so long as the Optionee serves as an employee of the Successor
Corporation. Following such assumption or substitution, if the Optionee's status
as an employee is terminated other than upon a voluntary resignation by the
Optionee, the Option shall become fully vested and exercisable in accordance
with Section 7 above.

     (a) 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 thirty (30) days
     from the date of such notice, and upon the expiration of such period the
     Option shall terminate.

     (b) For the purposes of this Section 10, 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 Board 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.  EMPLOYER WITHHOLDING. In the case of non-qualified stock options, the
Corporation shall be required to withhold additional income taxes attributable
to that amount which is considered compensation includible in the optionee's
gross income by reason of the exercise of such options. The Corporation in its
discretion shall determine the method and amount of withholding.


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12.  EXERCISE BY SUCCESSORS AND PAYMENT IN FULL. An option may be exercised, and
payment in full of the option price made, by the Successors of an Optionee only
by written notice (in the form prescribed by the Board of Directors) to the
Corporation specifying the number of Shares to be purchased. Such notice shall
state that the option price will be paid in full in cash (which in the
discretion of the Board of Directors may be obtained through a loan from the
Corporation or from a third party and guaranteed by the Corporation), property
or stock of the Corporation in conformance with paragraph 9 hereof. As soon as
practicable after receipt by the Corporation of such notice and of payment in
full of the option price of all the Shares with respect to which an option has
been exercised, a certificate or certificates representing such Shares shall be
registered (subject to the provisions of paragraph 16 hereof) in the name or
names of such Successors of an Optionee and shall be delivered to him.

13.  NON-TRANSFERABILITY OF OPTION. Each option granted under the Plan shall by
its terms be nontransferable by the optionee except by will or the laws of
descent and distribution of the state wherein the optionee is domiciled at the
time of his death. If the Administrator makes an Option transferable, such
Option shall contain such additional terms and conditions, as the Administrator
deems appropriate.

14.  OTHER TERMS OF OPTION. Options granted pursuant to the Plan shall contain
such terms, provisions, and conditions not inconsistent herewith as shall be
determined by the Board of Directors.

15.  REGISTRATION OF CERTIFICATES. Certificates representing Shares may be
registered either in the name of the Optionee or in the name or names of the
Successors of an Optionee. Designation of the appropriate form of registration
of certificates shall be made in the written notice given to the Corporation
upon exercise of an option.

16.  LISTING AND REGISTRATION OF SHARES. If at any time the Board of Directors
of the Corporation shall determine, in its discretion, that the listing,
registration, or qualification of any of the Shares subject to options under the
Plan upon any securities exchange or under any state or federal law, or the
consent or approval of any governmental regulatory body is necessary or
desirable as a condition of or in connection with the granting of options or the
purchase or issue of Shares thereunder, no further options may be granted and
outstanding options may not be exercised in whole or in part unless and until
such listing, registration, qualification, consent, or approval shall have been
effected or obtained free of any conditions not acceptable to the Board of
Directors. The Board of Directors shall have the authority to cause the
Corporation at its expense to take any action related to the Plan which may be
required in connection with such listing, registration, qualification, consent,
or approval. The Board of Directors may require that any person exercising an
option hereunder shall make such representations and agreements and furnish such
information as it deems appropriate to assure compliance with the foregoing or
any other applicable legal requirement.


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17.  INTERPRETATION AND AMENDMENTS. The Board of Directors may make such rules
and regulations and establish such procedure for the administration of the Plan
as it deems appropriate. In the event of any dispute or disagreements as to the
interpretation of this Plan or of any rule, regulation, or procedure, or as to
any question, right or obligation arising from or related to the Plan, the
decision of the Board of Directors shall be final and binding upon all persons.
The Board of Directors may amend this Plan as it shall deem advisable. However,
in no event shall any such amendment adversely affect the rights of an optionee
under any existing stock option agreement without the consent of such optionee.
In addition, no amendment may, without further approval of the shareholders of
the Company within twelve months before or after the date on which such
amendment was adopted, (a) increase the total number of shares which may be made
subject of options granted under the Plan, (b) change the manner of determining
the option price, (c) change the criteria of determining which employees are
eligible to receive options, (d) extend the period during which options may be
granted or exercised, or (e) withdraw the administration of the Plan from the
Board of Directors.

18.  INDEMNIFICATION AND EXCULPATION.

     (a) Each person who is or shall have been a member of the Board of
     Directors shall be indemnified and held harmless by the Corporation against
     and from any and all loss, cost, liability, or expense that may be imposed
     upon or reasonably incurred by him in connection with or resulting from any
     claim, action, suit, or proceeding to which he may be or become a party or
     in which he may be or become involved by reason of any action taken or
     failure to act under the Plan and against and from any and all amounts paid
     by him in settlement thereof (with the Corporation's written approval) or
     paid by him in satisfaction of a judgment in any such action, suit, or
     proceeding, except a judgment in favor of the Corporation based upon a
     finding of his lack of good faith; subject, however, to the condition that
     upon the institution of any claim, action, suit, or proceeding against him,
     he shall in writing give the Corporation an opportunity, at its own
     expense, to handle and defend the same before he undertakes to handle and
     defend it on his own behalf. The foregoing right of indemnification shall
     not be exclusive of any other right to which such person may be entitled as
     a matter of law or otherwise, or any power that the Corporation may have to
     indemnify him or hold him harmless.

     (b) Each member of the Board of Directors, and each officer and employee of
     the Corporation shall be fully justified in relying or acting in good faith
     upon any information furnished in connection with the administration of the
     Plan by any appropriate person or persons other than himself. In no event
     shall any person who is or shall have been a member of the Board of
     Directors, or an officer or employee of the Corporation be held liable for
     any determination made or other action taken or any omission to act in
     reliance upon any such information, or for any action (including the
     furnishing of information) taken or any failure to act, if in good faith.


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19.  CHANGES IN CAPITAL STRUCTURE. In the event that a dividend shall be
declared upon the Shares payable in Shares, the number of shares then subject to
any option outstanding under the Plan and the number of Shares reserved for the
grant of options pursuant to the Plan but not yet subject to option shall be
adjusted by adding to each such Share the number of Shares which would be
distributable in respect thereof if such Shares had been outstanding on the date
fixed for determining the shareholders of the Corporation entitled to receive
such Share dividend. In the event that the outstanding Shares shall be changed
into or exchanged for a different number of Shares or other securities of the
Corporation or of another corporation, whether through reorganization,
recapitalization, split-up, combination of shares, merger, or consolidation,
then there shall be substituted for each Share subject to any such option and
for each Share reserved for the grant of options pursuant to the Plan but not
yet subject to option the number and kind of Shares or other securities into
which each outstanding Share shall have been so changed or for which each such
share shall have been exchanged. In the event there shall be any change, other
than as specified above in this paragraph, in the number or kind of outstanding
Shares or of any shares or other securities into which such Shares shall have
been changed or for which they shall have been exchanged, then if the Board of
Directors shall in its sole discretion determine that such change equitably
requires an adjustment in the number or kind of Shares theretofore reserved for
the grant of options pursuant to the Plan but not yet subject to option and of
the Shares then subject to an option or options. Such adjustments shall be made
by the Board of Directors and shall be effective and binding for all purposes of
the Plan and of each option outstanding thereunder. In the case of any such
substitution or adjustment as provided for in this paragraph, the aggregate
option exercise price set forth for all outstanding options for all Shares
covered thereby prior to such substitution or adjustment will be the option
exercise price for all shares or other securities which shall have been adjusted
pursuant to this paragraph. No adjustment or substitution provided for in this
paragraph shall require the Corporation to sell a fractional Share, and the
total substitution or adjustment with respect to each outstanding option shall
be limited accordingly. Upon any adjustment made pursuant to this paragraph, the
Corporation will, upon request, deliver to the optionee or to his successors a
certificate setting forth the option price thereafter in effect and the number
and kind of shares or other securities thereafter purchasable on the exercise of
the option.

20.  NOTICES. All notices under the Plan shall be in writing, and if to the
Corporation, shall be delivered to the Treasurer of the Corporation or mailed to
its principal office, addressed to the attention of the Treasurer; and if to the
optionee, shall be delivered personally or mailed to the optionee at the address
appearing in the payroll records of the Corporation. Such addresses may be
changed at any time by written notice to the other party.

21.  CORPORATION'S OPTION. As of the date of the adoption of the Plan, the
Corporation intends to commence an initial public offering of shares of its
Common Stock. Until such time as such offering is completed, the Corporation
shall have the right to purchase from any optionee (or his or her successor,
assignee or transferee) shares of common stock issued upon the exercise of
options granted hereunder for a price per share equal to the exercise price per
share paid for such shares.