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Exhibit 10(b)

                               INTERPHASE CORPORATION

                       AMENDED AND RESTATED STOCK OPTION PLAN

    WHEREAS, on August 24, 1984, the Board of Directors (the "Board") of
Interphase Corporation adopted the Interphase Corporation Incentive Stock Option
Plan (the "Plan"); and
    WHEREAS, the Board subsequently amended the Plan from time to time to
increase the number of shares of common stock of the Company available under the
Plan from 200,000 shares to 1,350,000 shares and to make certain changes to the
Plan; and
    WHEREAS, the Board now desires to amend and restate the Plan, and in
connection therewith, add provisions to the Plan to allow the grant of
non-qualified stock options and to rename the Plan the Interphase
Corporation Amended and Restated Stock Option Plan;
    NOW, THEREFORE, in consideration of the foregoing, the Board hereby adopts
the Amended and Restated Stock Option Plan effective November 9, 1994:
         1.   PURPOSE.  The purpose of the Plan is to continue to provide
    selected employees with a proprietary interest in the Company through the
    granting of either incentive stock options or non-qualified stock options
    which will
              (a)  increase the interest of the selected employees in the
         Company's welfare;
              (b)  furnish an incentive to the selected employees to continue
         their services for the Company; and
              (c)  provide a means through which the Company may attract able
         persons to enter its employ.

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         2.   ADMINISTRATION.  The Plan will be administered by the Board.
         3.   PARTICIPANTS.  The Board shall, from time to time, select the
    particular employees of the Company and its Subsidiaries to whom options
    are to be granted, and who will, upon such grant, become participants in
    the Plan.
         4.   STOCK OWNERSHIP LIMITATIONS.  No Incentive Option may be granted
    to an employee who owns more than 10% of the voting power of all classes of
    stock of the Company or its Parent or Subsidiaries.  This limitation will
    not apply if the option price is at least 110% of the fair market value of
    the stock at the time the Incentive Option is granted and the Incentive
    Option is not exercisable more than five years from the date it is granted.
         5.   SHARES SUBJECT TO PLAN.  The Board may not grant options under
    the Plan for more than 1,350,000 shares of Common Stock of the Company, but
    this number may be adjusted to reflect, if deemed appropriate by the Board,
    any stock dividend, stock split, share combination, recapitalization or the
    like, of or by the Company.  Shares to be optioned and sold may be made
    available from either authorized but unissued Common Stock or Common Stock
    held by the Company in its treasury.  Shares that by reason of the
    expiration of an option or otherwise are no longer subject to purchase
    pursuant to an option granted under the Plan may be reoffered under the
    Plan.
         6.   LIMITATION ON AMOUNT.  The aggregate fair market value
    (determined at the time of grant) of the shares of Common Stock which any
    employee is

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    first eligible to purchase in any calendar year by exercise of
    Incentive Options granted under this Plan and all incentive stock option
    plans (within the meaning of Section 422 of the Internal Revenue Code) of
    the Company or its Parent or Subsidiaries shall not exceed $100,000.  For
    this purpose, the fair market value (determined at the respective date of
    grant of each option) of the stock purchasable by exercise of an Incentive
    Option (or an installment thereof) shall be counted against the $100,000
    annual limitation for an employee only for the calendar year such stock is
    first purchasable under the terms of the Incentive Option.
         7.   ALLOTMENT OF SHARES.  The Board shall determine the number of
    shares of Common Stock to be offered from time to time by grant of options
    to employees of the Company or its Subsidiaries.  The grant of an option to
    an employee shall not be deemed either to entitle the employee to, or to
    disqualify the employee from, participation in any other grant of options
    under the Plan.
         8.   GRANT OF OPTIONS.  The Board is authorized to grant Incentive
    Options and Nonqualified Options under the Plan.  The grant of options
    shall be evidenced by stock option agreements containing such terms and
    provisions as are approved by the Board, but not inconsistent with the
    Plan, including provisions that may be necessary to assure that any option
    that is intended to be an Incentive Option will comply with Section 422 of
    the Internal Revenue Code.  The Company shall execute stock option
    agreements upon instructions from the Board.  The Plan shall be submitted
    to the Company's stockholders for

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    approval.  The Board may grant options under the Plan prior to the time
    of stockholder approval, which options will be effective when granted,
    but if for any reason the stockholders of the Company do not approve the
    Plan prior to one year from the date of adoption of the Plan by the
    Board, all options granted under the Plan will be terminated and of no
    effect, and no option may be exercised in whole or in part prior to such
    stockholder approval.
         A stock option agreement may provide that the participant may request
    approval from the Board to exercise an option or a portion thereof by
    tendering shares of Common Stock at the fair market value per share on the
    date of exercise in lieu of cash payment of the exercise price.
         9.   OPTION PRICE.  The option price shall not be less than 100% of
    the fair market value per share of the Common Stock on the date the option
    is granted.
         10.  OPTION PERIOD.  The Option Period will begin on the date the
    option is granted, which will be the date the Board authorizes the option
    unless the Board specifies a later date.  No option may terminate later
    than 10 years from the date the option is granted.  The Board may provide
    for the exercise of options in installments and upon such terms, conditions
    and restrictions as it may determine.  The Board may provide for
    termination of the option in the case of termination of employment or any
    other reason.
         11.  RIGHTS IN THE EVENT OF DEATH OR DISABILITY.  If a participant
    dies or becomes disabled [within the meaning of Section 22(e)(3) of the
    Internal Revenue

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    Code] while in the employ of the Company but prior to termination of
    his right to exercise an option in accordance with the provisions
    of his stock option agreement without having totally exercised the
    option, the option may be exercised, to the extent of the shares with
    respect to which the option could have been exercised by the participant on
    the date of the participant's death or disability, by (i) the participant's
    estate or by the person who acquired the right to exercise the option by
    bequest or inheritance or by reason of the death of the participant in the
    event of the participant's death, or (ii) the participant or his personal
    representative in the event of the participant's disability, provided the
    option is exercised prior to the date of its expiration or not more than
    one year from the date of the participant's death or disability whichever
    first occurs.
         12.  PAYMENT.  Full payment for shares purchased upon exercising an
    option shall be made in cash or by check or, if permitted by the stock
    option agreement, by tendering shares of Common Stock at the fair market
    value per share at the time of exercise, or on such other terms as are set
    forth in the applicable option agreement.  No shares may be issued until
    full payment of the purchase price therefore has been made, and a
    participant will have none of the rights of a stockholder until shares are
    issued to him.
         13.  EXERCISE OF OPTION.  Options granted under the Plan may be
    exercised during the Option Period, at such times, in such amounts, in
    accordance with such terms and subject to such restrictions as are set
    forth in the applicable stock option agreements.  In no event may an option
    be exercised or shares be issued pursuant to an option if any

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    requisite action, approval or consent of any governmental authority of any
    kind having jurisdiction over the exercise of options shall not have been
    taken or secured.
         14.  CAPITAL ADJUSTMENTS AND REORGANIZATIONS.  The number of shares of
    Common Stock covered by each outstanding option granted under the Plan and
    the option price may be adjusted to reflect, as deemed appropriate by the
    Board, any stock dividend, stock split, share combination or the like of or
    by the Company.  In the event of a merger, consolidation, share exchange,
    reorganization, liquidation, recapitalization, separation or the like of or
    by the Company, the Board may make such arrangements as it deems advisable
    with respect to outstanding options granted under the Plan, which
    arrangements shall be binding upon each employee that holds an outstanding
    option granted under the Plan, including, but not limited to, arrangements
    for the substitution of new options for any options then outstanding, the
    assumption of any such options, payment for the outstanding options and
    adjusting the number of shares covered by each outstanding option and the
    option price therefor.  Any such arrangement relating to an Incentive
    Option shall comply with the requirements of Internal Revenue Code Section
    422 and the regulations thereunder.  If the Company becomes a party to an
    agreement providing for the merger, consolidation or share exchange of or
    by the Company and pursuant to that agreement the holders of Common Stock
    would receive cash, securities or property from another person or entity
    and if the Board does not make arrangements for the substitution of new
    options for any options then outstanding, the assumption of such options,
    or payment

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    for such options, the Plan shall terminate and any options outstanding
    hereunder shall terminate on the effective date of such transaction;
    provided, however, all outstanding options granted under the Plan
    shall become immediately exercisable during the five business days
    immediately preceding the effective date of such transaction.  If the
    options will so terminate on the effective date of the transaction, the
    Company shall give each Option Holder at least 15 days' notice of such
    termination and an opportunity to exercise such options prior to such
    termination.
         15.  NON-ASSIGNABILITY.  Options may not be transferred other than by
    will or by the laws of descent and distribution.  During a participant's
    lifetime, options granted to a participant may be exercised only by the
    participant.
         16.  INTERPRETATION.  The Board shall interpret the Plan and shall
    prescribe such rules and regulations in connection with the operation of
    the Plan as it determines to be advisable for the administration of the
    Plan.  The Board may rescind and amend its rules and regulations.
         17.  AMENDMENT OR DISCONTINUANCE.  The Plan may be amended or
    discontinued by the Board without the approval of the stockholders of the
    Company, except that any amendment that would (a) materially increase the
    benefits accruing to participants under the Plan, (b) materially increase
    the number of securities that may be issued under the Plan, or (c)
    materially modify the requirements or eligibility for participation in the
    Plan must be approved by the stockholders of the Company.

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         18.  EFFECT OF PLAN.  Neither the adoption of the Plan nor any action
    of the Board shall be deemed to give any officer or employee any right to
    be granted an option to purchase Common Stock of the Company or any other
    rights except as may be evidenced by a stock option agreement, or any
    amendment thereto, duly authorized by the Board and executed on behalf of
    the Company and then only to the extent and on the terms and conditions
    expressly set forth therein.
         19.  TERM.  Unless sooner terminated by action of the Board, this Plan
    will terminate on November 8, 2004.  The Board may not grant options under
    the Plan after that date, but options granted before that date will
    continue to be effective in accordance with their terms.
         20.  DEFINITIONS.  For the purpose of this Plan, unless the context
    requires otherwise, the following terms shall have the meanings indicated:
              (a)  "Plan" means this Amended and Restated Stock Option Plan as
         amended from time to time.
              (b)  "Company" means Interphase Corporation, a Texas corporation.
              (c)  "Board" means the board of directors of the Company or a
         committee appointed by the board of directors to administer the Plan
         or any portion of the Plan.
              (d)  "Common Stock" means the Common Stock which the Company is
         currently authorized to issue or may in the future be authorized to
         issue (as long as

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         the common stock varies from that currently authorized, if at all,
         only in amount of par value).
              (e)  "Subsidiary" means any corporation in an unbroken chain of
         corporations beginning with the Company if, at the time of the
         granting of the option, each of the corporations other than the last
         corporation in the unbroken chain owns stock possessing 50% or more of
         the total combined voting power of all classes of stock in one of the
         other corporations in the chain, and "Subsidiaries" means more than
         one of any such corporations.
              (f)  "Parent" means any corporation in an unbroken chain of
         corporations ending with the Company if, at the time of granting of
         the option, each of the corporations other than the Company owns stock
         possessing 50% or more of the total combined voting power of all
         classes of stock in one of the other corporations in the chain.
              (g)  "Option Period" means the period during which an option may
         be exercised.
              (h)  "Incentive Option" means an option granted under the Plan
         which meets the requirements of Section 422 of the Internal Revenue
         Code.
              (i)  "Nonqualified Stock Option" means an option granted under
         the Plan which is not intended to be an Incentive Option.

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                                   AMENDMENT NO. 1
                                        TO THE
                                INTERPHASE CORPORATION
                        AMENDED AND RESTATED STOCK OPTION PLAN


    Pursuant to Section 17 of the Interphase Corporation Amended and Restated
Stock Option Plan (the "Plan"), the Plan is hereby amended as follows:
    1.   Section 9 of the Plan is hereby amended to read in its entirety as
follows:
         Section 9.  OPTION PRICE.  The option price for Incentive Options
    shall not be less than 100% of the fair market value per share of the
    Common Stock on the date the Incentive Option is granted.  The option price
    for Nonqualified Options shall be, as determined by the Board, any price
    per share of the Common Stock that is greater than par value per share of
    the Common Stock.

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    IN WITNESS WHEREOF, the undersigned has executed this Amendment effective
as of the 22nd day of March, 1995.

                                             INTERPHASE CORPORATION


                                          By /s/ R. STEPHEN POLLEY
                                             -----------------------------




                                   AMENDMENT NO. 2
                                        TO THE
                                INTERPHASE CORPORATION
                        AMENDED AND RESTATED STOCK OPTION PLAN


    Pursuant to Section 17 of the Interphase Corporation Amended and Restated
Stock Option Plan (the "Plan"), the Plan is hereby amended as follows:
    1.   Section 5 of the Plan is hereby amended to read in its entirety as
follows:
         5.   SHARES SUBJECT TO PLAN.  The Board may not grant options under
    the Plan for more than 2,350,000 shares of Common Stock of the Company, but
    this number may be adjusted to reflect, if deemed appropriate by the Board,
    any stock dividend, stock split, share combination, recapitalization or the
    like, of or by the Company.  Shares to be optioned and sold may be made
    available from either authorized but unissued Common Stock or Common Stock
    held by the Company in its treasury.  Shares that by reason of the
    expiration of an option or otherwise are no longer subject to purchase

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    pursuant to an option granted under the Plan may be reoffered under the
    Plan.

    IN WITNESS WHEREOF, the undersigned has executed this Amendment effective
as of the 25th day of June, 1996.


                                        INTERPHASE CORPORATION


                                        By /s/ R. STEPHEN POLLEY
                                           ------------------------------




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