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                                                                     EXHIBIT 4.3

                             TranSwitch Corporation
                  Form of Non-Qualified Stock Option Agreement
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     TranSwitch Corporation (the "Company") hereby grants the following stock
option pursuant to its 2000 Stock Option Plan.  The terms and  conditions
attached hereto are also a  part hereof.

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Name of Optionee (the "Optionee"):
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Date of this option grant:
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Number of shares of the Company's Common Stock
subject to this option ("Option Shares"):
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Option exercise price per share:
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Number, if any, of Option Shares that may be
purchased on or after grant date:
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Number of Option Shares subject to vesting
schedule:
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Vesting Start Date:
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     Vesting Schedule:
     ----------------

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[Date]
                                                                _________ shares
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[Date]

                                                     an additional ______ shares
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[Date]

                                                     an additional ______ shares
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[Date]

                                                     an additional ______ shares
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Payment alternatives (specify any or all of
Section 7(a)(i) though (iv):

                                                  Section 7(a) (i) through (___)
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                                                   TranSwitch Corporation
____________________________________
Signature of Optionee                              By:_________________________
                                                      Name of Officer:
____________________________________                  Title:
Street Address

____________________________________
City/State/Zip Code
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                             TranSwitch Corporation

          Stock Option Agreement -- Incorporated Terms and Conditions
          -----------------------------------------------------------


     1.  Grant Under Plan.  This option is granted pursuant to and is governed
by the Company's 2000 Stock Option Plan (the "Plan") and, unless the context
otherwise requires, terms used herein shall have the same meaning as in the
Plan.

     2.  Grant as Non-Qualified Stock Option.  This option is a non-statutory
stock option and is not intended to qualify as an incentive stock option under
Section 422 of the Internal Revenue Code of 1986, as amended, and the
regulations thereunder (the "Code").

     3.  Vesting of Option if Business Relationship  Continues.  The Optionee
may exercise this option on or after the date of this option grant for the
number of shares of Common Stock, if any, indicated on the cover page hereof.
If the Optionee has continuously engaged in a business relationship with the
Company through the dates listed on the vesting schedule set forth on the cover
page hereof, the Optionee may exercise this option for the additional number of
shares of Common Stock set opposite the applicable vesting date.
Notwithstanding the foregoing, the Board may, in its discretion, accelerate the
date that any installment of this option becomes exercisable.  The foregoing
rights are cumulative and (subject to Sections 4 or 5 hereof if the Optionee
ceases to be employed by the Company) may be exercised only before the date
which is seven years from the date of this option grant.

     4.  Termination of Business Relationship.

          (a) Termination Other Than for Cause.  If the Optionee ceases to be
     engaged in a business relationship with the Company, other than by reason
     of death or disability as defined in Section 5 or termination for Cause as
     defined in Section 4(c), no further installments of this option shall
     become exercisable, and this option may no longer be exercised after the
     passage of three months from the Optionee's last day of the business
     relationship, but in no event later than the scheduled expiration date.
     For purposes hereof, if the optionee is a natural person, the business
     relationship shall not be considered as having terminated during any leave
     of absence if such leave of absence has been approved in writing by the
     Company and if such written approval contractually obligates the Company to
     continue the business relationship with the Optionee after the approved
     period of absence; in the event of such an approved leave of absence,
     vesting of this option shall be suspended (and the period of the leave of
     absence shall be added to all vesting dates) unless otherwise provided in
     the Company's written approval of the leave of absence. For purposes
     hereof, business relationship shall include a consulting arrangement
     between the Optionee and the Company that immediately follows termination
     of employment, but only if so stated in a written consulting agreement
     executed by the Company that specifically refers to this option.  This
     option shall not be affected by any change of employment within or among
     the Company and its Subsidiaries
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     so long as the Optionee continuously maintains a business relationship with
     the Company or any Subsidiary.

          (b) Termination for Cause.  If the business relationship of the
     Optionee is terminated for Cause (as defined in Section 4(c)), this option
     shall no longer be exercised from and after the Optionee's receipt of
     written notice of such termination.

          (c) Definition of Cause.  "Cause" shall mean conduct involving one or
     more of the following: (i) the substantial and continuing failure of the
     Optionee, after notice thereof, to render services to the Company in
     accordance with the terms or requirements of his or her business
     relationship; (ii) disloyalty, gross negligence, willful misconduct,
     dishonesty, fraud or breach of fiduciary duty to the Company;  (iii)
     deliberate disregard of the rules or policies of the Company, or breach of
     an employment or other agreement with the Company, which results in direct
     or indirect loss, damage or injury to the Company; (iv) the unauthorized
     disclosure of any trade secret or confidential information of the Company;
     or (v) the commission of an act which constitutes unfair competition with
     the Company or which induces any customer or supplier to breach a contract
     with the Company.

     5.  Death; Disability.

          (a) Death.  If the Optionee is a natural person who dies while in a
     business relationship with the Company, this option may be exercised, to
     the extent otherwise exercisable on the date of his or her death, by the
     Optionee's estate, personal representative or beneficiary to whom this
     option has been transferred pursuant to Section 9, only at any time within
     180 days after the date of death, but not later than the scheduled
     expiration date.

          (b) Disability.  If the Optionee is a natural person who ceases to be
     engaged in a business relationship with the Company by reason of his or her
     disability, this option may be exercised, to the extent otherwise
     exercisable on the date of cessation of employment, only at any time within
     180 days after such cessation of employment, but not later than the
     scheduled expiration date.  For purposes hereof, "disability" means
     "permanent and total disability" as defined in Section 22(e)(3) of the
     Code.

     6.  Partial Exercise.  This option may be exercised in part at any time and
from time to time within the above limits, except that this option may not be
exercised for a fraction of a share.

     7.  Payment of Exercise Price.

          (a)  Payment Options.  The exercise price shall be paid by one or any
     combination of the following forms of payment that are applicable to this
     option, as indicated on the cover page hereof:
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         (i)   by check payable to the order of the Company; or

         (ii)  if the Common Stock is then traded on a national securities
               exchange or on the Nasdaq National Market (or successor trading
               system), delivery of an irrevocable and unconditional
               undertaking, satisfactory in form and substance to the Company,
               by a creditworthy broker to deliver promptly to the Company
               sufficient funds to pay the exercise price, or delivery by the
               Optionee to the Company of a copy of irrevocable and
               unconditional instructions, satisfactory in form and substance to
               the Company, to a creditworthy broker to deliver promptly to the
               Company cash or a check sufficient to pay the exercise price; or

         (iii) subject to Section 7(b) below, if the Common Stock is then
               traded on a national securities exchange or on the Nasdaq
               National Market (or successor trading system), by delivery of
               shares of  Common Stock having a fair market value equal as of
               the date of exercise to the option price; or

         (iv)  by check payable to the order of the Company for the par value of
               the shares being purchased plus delivery of the Optionee's
               [three]-year personal full recourse promissory note for the
               balance of the exercise price, with such note bearing interest
               payable not less than annually at the applicable Federal rate, as
               defined in Section 1274(d) of the Code.

          In the case of (iii) above, fair market value as of the date of
     exercise shall be determined as of the last business day for which such
     prices or quotes are available prior to the date of exercise and shall mean
     (i) the last reported sale price (on that date) of the Common Stock on the
     principal national securities exchange on which the Common Stock is traded,
     if the Common Stock is then traded on a national securities exchange; or
     (ii) the last reported sale price (on that date) of the Common Stock on the
     Nasdaq National Market (or successor trading system), if the Common Stock
     is not then traded on a national securities exchange.

          (b) Limitations on Payment by Delivery of Common Stock.  If Section
     7(a)(iii) is applicable, and if the Optionee delivers Common Stock held by
     the Optionee ("Old Stock") to the Company in full or partial payment of the
     exercise price and the Old Stock so delivered is subject to restrictions or
     limitations imposed by agreement between the Optionee and the Company, an
     equivalent number of Option Shares shall be subject to all restrictions and
     limitations applicable to the Old Stock to the extent that the Optionee
     paid for the Option Shares by delivery of Old Stock, in addition to any
     restrictions or limitations imposed by this Agreement.  Notwithstanding the
     foregoing, the Optionee may not pay any part of the exercise price hereof
     by transferring Common Stock to the Company unless such Common Stock has
     been owned by the Optionee free of any substantial risk of forfeiture for
     at least six months.
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     8.  Method of Exercising Option.  Subject to the terms and conditions of
this Agreement, this option may be exercised by written notice to the Company at
its principal executive office, or to such transfer agent as the Company shall
designate.  Such notice shall state the election to exercise this option and the
number of Option Shares for which it is being exercised and shall be signed by
the person or persons so exercising this option.  Such notice shall be
accompanied by payment of the full purchase price of such shares, and the
Company shall deliver a certificate or certificates representing such shares as
soon as practicable after the notice shall be received.  Such certificate or
certificates shall be registered in the name of the person or persons so
exercising this option (or, if this option shall be exercised by the Optionee
and if the Optionee shall so request in the notice exercising this option, shall
be registered in the name of the Optionee and another person jointly, with right
of survivorship). In the event this option shall be exercised, pursuant to
Section 5 hereof, by any person or persons other than the Optionee, such notice
shall be accompanied by appropriate proof of the right of such person or persons
to exercise this option.

     9.  Option Not Transferable.  This option is not transferable or assignable
except by will or by the laws of descent and distribution or pursuant to a valid
domestic relations order.  During the Optionee's lifetime only the Optionee can
exercise this option.

     10.  No Obligation to Exercise Option.  The grant and acceptance of this
option imposes no obligation on the Optionee to exercise it.

     11.  No Obligation to Continue Employment.  Neither the Plan, this
Agreement, nor the grant of this option imposes any obligation on the Company to
continue the Optionee in employment.

     12.  Adjustments.  Except as is expressly provided in the Plan with respect
to certain changes in the capitalization of the Company, no adjustment shall be
made for dividends or similar rights for which the record date is prior to such
date of exercise.

     13.  Withholding Taxes.  If the Company in its discretion determines that
it is obligated to withhold any tax in connection with the exercise of this
option, or in connection with the transfer of, or the lapse of restrictions on,
any Common Stock or other property acquired pursuant to this option, the
Optionee hereby agrees that the Company may withhold from the Optionee's wages
or other remuneration the appropriate amount of tax.  At the discretion of the
Company, the amount required to be withheld may be withheld in cash from such
wages or other remuneration or in kind from the Common Stock or other property
otherwise deliverable to the Optionee on exercise of this option.  The Optionee
further agrees that, if the Company does not withhold an amount from the
Optionee's wages or other remuneration sufficient to satisfy the withholding
obligation of the Company, the Optionee will make reimbursement on demand, in
cash, for the amount underwithheld.

     14.  Arbitration.  Any dispute, controversy, or claim arising out of, in
connection with, or relating to the performance of this Agreement or its
termination shall be settled by arbitration in the State of Connecticut,
pursuant to the rules then obtaining of the American Arbitration
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Association. Any award shall be final, binding and conclusive upon the parties
and a judgment rendered thereon may be entered in any court having jurisdiction
thereof.

     15.  Provision of Documentation to Optionee.  By signing this Agreement the
Optionee acknowledges receipt of a copy of this Agreement and a copy of the
Plan.

     16.  Miscellaneous.

          (a) Notices.  All notices hereunder shall be in writing and shall be
     deemed given when sent by certified or registered mail, postage prepaid,
     return receipt requested, if to the Optionee, to the address set forth
     below or at the address shown on the records of the Company, and if to the
     Company, to the Company's principal executive offices, attention of the
     Corporate Secretary.

          (b) Entire Agreement; Modification.  This Agreement constitutes the
     entire agreement between the parties relative to the subject matter hereof,
     and supersedes all proposals, written or oral, and all other communications
     between the parties relating to the subject matter of this Agreement.  This
     Agreement may be modified, amended or rescinded only by a written agreement
     executed by both parties.

          (c)   Fractional Shares.  If this option becomes exercisable for a
     fraction of a share because of the adjustment provisions contained in the
     Plan, such fraction shall be rounded down.

          (d) Issuances of Securities; Changes in Capital Structure. Except as
     expressly provided herein or in the Plan, 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 this
     option.  No adjustments need be made for dividends paid in cash or in
     property other than securities of the Company. If there shall be any change
     in the Common Stock of the Company through merger, consolidation,
     reorganization, recapitalization, stock dividend, stock split, combination
     or exchange of shares, liquidation, spin-off, split-up or other similar
     change in capitalization or event,  the restrictions contained in this
     Agreement shall apply with equal force to additional and/or substitute
     securities, if any, received by the Optionee in exchange for, or by virtue
     of his or her ownership of, Option Shares, except as otherwise determined
     by the Board.

          (e) Severability.  The invalidity, illegality or unenforceability of
     any provision of this Agreement shall in no way affect the validity,
     legality or enforceability of any other provision.

          (f) Successors and Assigns.  This Agreement shall be binding upon and
     inure to the benefit of the parties hereto and their respective successors
     and assigns, subject to the limitations set forth in Section 9 hereof.
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     (g) Governing Law.  This Agreement shall be governed by and interpreted in
     accordance with the laws of the State of Delaware, without giving effect to
     the principles of the conflicts of laws thereof.