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                                                                    Exhibit 10.1


                       QUANTUM BRIDGE COMMUNICATIONS, INC.

                           SECOND AMENDED AND RESTATED
                            1998 STOCK INCENTIVE PLAN
                                   AS AMENDED


1.       Purpose

         The purpose of this Second Amended and Restated 1998 Stock Incentive
Plan, as amended (the "Plan") of Quantum Bridge Communications, Inc., formerly
MetroWeb Technologies, Inc., a Delaware corporation (the "Company"), is to
advance the interests of the Company's stockholders by enhancing the Company's
ability to attract, retain and motivate persons who make (or are expected to
make) important contributions to the Company by providing such persons with
equity ownership opportunities and performance-based incentives and thereby
better aligning the interests of such persons with those of the Company's
stockholders. Except where the context otherwise requires, the term "Company"
shall include any of the Company's present or future subsidiary corporations as
defined in Section 424(f) of the Internal Revenue Code of 1986, as amended, and
any regulations promulgated thereunder (the "Code").

2.       Eligibility

         All of the Company's employees, officers, directors, consultants and
advisors (and any individuals who have accepted an offer for employment) are
eligible to be granted options, restricted stock awards, or other stock-based
awards (each, an "Award") under the Plan. Each person who has been granted an
Award under the Plan shall be deemed a "Participant".

3.       Administration, Delegation

         (a)      Administration by Board of Directors. The Plan will be
administered by the Board of Directors of the Company (the "Board"). The Board
shall have authority to grant Awards and to adopt, amend and repeal such
administrative rules, guidelines and practices relating to the Plan as it shall
deem advisable. The Board may correct any defect, supply any omission or
reconcile any inconsistency in the Plan or any Award in the manner and to the
extent it shall deem expedient to carry the Plan into effect and it shall be the
sole and final judge of such expediency. All decisions by the Board shall be
made in the Board's sole discretion and shall be final and binding on all
persons having or claiming any interest in the Plan or in any Award. No director
or person acting pursuant to the authority delegated by the Board shall be
liable for any action or determination relating to or under the Plan made in
good faith.

         (b)      Delegation to Executive Officers. To the extent permitted by
applicable law, the Board may delegate to one or more executive officers of the
Company the


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power to make Awards and exercise such other powers under the Plan as the Board
may determine, provided that the Board shall fix the maximum number of shares
subject to Awards and the maximum number of shares for any one Participant to be
made by such executive officers.

         (c)      Appointment of Committees. To the extent permitted by
applicable law, the Board may delegate any or all of its powers under the Plan
to one or more committees or subcommittees of the Board (a "Committee"). All
references in the Plan to the "Board" shall mean the Board or a Committee of the
Board or the executive officer referred to in Section 3(b) to the extent that
the Board's powers or authority under the Plan have been delegated to such
Committee or executive officer.

         If and when the common stock, .001 par value per share, of the Company
(the "Common Stock") is registered under the Securities Exchange Act of 1934
(the "Exchange Act"), the Board shall appoint one such Committee of not less
than two members, each member of which shall be an "outside director" within the
meaning of Section 162(m) of the Code and a "non-employee director" as defined
in Rule 16b-3 promulgated under the Exchange Act.

4.       Stock Available for Awards

         (a)      Number of Shares. Subject to adjustment under Section 8,
Awards may be made under the Plan for up to 12,150,000 shares of Common Stock.
If any Award expires or is terminated, surrendered or canceled without having
been fully exercised or is forfeited in whole or in part or results in any
Common Stock not being issued, the unused Common Stock covered by such Award
shall again be available for the grant of Awards under the Plan, subject,
however, in the case of Incentive Stock Options (as hereinafter defined), to any
limitation required under the Code. Shares issued under the Plan may consist in
whole or in part of authorized but unissued shares or treasury shares.

         (b)      Per-Participant Limit. Subject to adjustment under Section 8,
for Awards granted after the Common Stock is registered under the Securities
Exchange Act of 1934 (the "Exchange Act"), the maximum number of shares of
Common Stock with respect to which an Award may be granted to any Participant
under the Plan shall be 800,000 per calendar year. The per-Participant limit
described in this Section 4(b) shall be construed and applied consistently with
Section 162(m) of the Code.

5.       Stock Options

         (a)      General. The Board may grant options to purchase Common Stock
(each, an "Option") and determine the number of shares of Common Stock to be
covered by each Option, the exercise price of each Option and the conditions and
limitations applicable to the exercise of each Option, including conditions
relating to applicable


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federal or state securities laws, as it considers necessary or advisable. An
Option which is not intended to be an Incentive Stock Option (as hereinafter
defined) shall be designated a "Nonstatutory Stock Option".

         (b)      Incentive Stock Options. An Option that the Board intends to
be an "incentive stock option" as defined in Section 422 of the Code (an
"Incentive Stock Option") shall only be granted to employees of the Company and
shall be subject to and shall be construed consistently with the requirements of
Section 422 of the Code. The Company shall have no liability to a Participant,
or any other party, if an Option (or any part thereof) which is intended to be
an Incentive Stock Option is not an Incentive Stock Option.

         (c)      Exercise Price. The Board shall establish the exercise price
at the time each Option is granted and specify it in the applicable option
agreement.

         (d)      Duration of Options. Each Option shall be exercisable at such
times and subject to such terms and conditions as the Board may specify in the
applicable option agreement, provided, however, that no Option will be granted
for a term in excess of 10 years.

         (e)      Exercise of Option. Options may be exercised by delivery to
the Company of a written notice of exercise signed by the proper person or by
any other form of notice (including electronic notice) approved by the Board
together with payment in full as specified in Section 5(f) for the number of
shares for which the Option is exercised.

         (f)      Payment Upon Exercise. Common Stock purchased upon the
exercise of an Option granted under the Plan shall be paid for as follows:

                  (1)      in cash or by check, payable to the order of the
Company;

                  (2)      except as the Board may, in its sole discretion,
otherwise provide in an option agreement, by (i) delivery of an irrevocable and
unconditional undertaking by a creditworthy broker to deliver promptly to the
Company sufficient funds to pay the exercise price or (ii) delivery by the
Participant to the Company of a copy of irrevocable and unconditional
instructions to a creditworthy broker to deliver promptly to the Company cash or
a check sufficient to pay the exercise price;

                  (3)      when the Common Stock is registered under the
Exchange Act, by delivery of shares of Common Stock owned by the Participant
valued at their fair market value as determined by (or in a manner approved by)
the Board in good faith ("Fair Market Value"), which Common Stock was owned by
the Participant at least six months prior to such delivery;


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                  (4)      to the extent permitted by the Board, in its sole
discretion, and specifically provided in the applicable option agreement, by (i)
delivery of a promissory note of the Participant to the Company on terms
determined by the Board, or (ii) payment of such other lawful consideration as
the Board may determine; or

                  (5)      by any combination of the above permitted forms of
payment.

6.       Restricted Stock

                  (a)      Grants. The Board may grant Awards entitling
recipients to acquire shares of Common Stock, subject to the right of the
Company to repurchase all or part of such shares at their issue price or other
stated or formula price (or to require forfeiture of such shares if issued at no
cost) from the recipient in the event that conditions specified by the Board in
the applicable Award are not satisfied prior to the end of the applicable
restriction period or periods established by the Board for such Award (each, a
"Restricted Stock Award").

                  (b)      Terms and Conditions. The Board shall determine the
terms and conditions of any such Restricted Stock Award, including the
conditions for repurchase (or forfeiture) and the issue price, if any. Any stock
certificates issued in respect of a Restricted Stock Award shall be registered
in the name of the Participant and, unless otherwise determined by the Board,
deposited by the Participant, together with a stock power endorsed in blank,
with the Company (or its designee). At the expiration of the applicable
restriction periods, the Company (or such designee) shall deliver the
certificates no longer subject to such restrictions to the Participant or if the
Participant has died, to the beneficiary designated, in a manner determined by
the Board, by a Participant to receive amounts due or exercise rights of the
Participant in the event of the Participant's death (the "Designated
Beneficiary"). In the absence of an effective designation by a Participant,
Designated Beneficiary shall mean the Participant's estate.

7.       Other Stock-Based Awards

         The Board shall have the right to grant other Awards based upon the
Common Stock having such terms and conditions as the Board may determine,
including the grant of shares based upon certain conditions, the grant of
securities convertible into Common Stock and the grant of stock appreciation
rights.

8.       Adjustments for Changes in Common Stock and Certain Other Events

         (a)      Changes in Capitalization. In the event of any stock split,
reverse stock split, stock dividend, recapitalization, combination of shares,
reclassification of shares, spin-off or other similar change in capitalization
or event, or any distribution to holders


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of Common Stock other than a normal cash dividend, (i) the number and class of
securities available under this Plan, (ii) the per-Participant limit set forth
in Section 4(b), (iii) the number and class of securities and exercise price per
share subject to each outstanding Option, (iv) the repurchase price per share
subject to each outstanding Restricted Stock Award, and (v) the terms of each
other outstanding Award shall be appropriately adjusted by the Company (or
substituted Awards may be made, if applicable) to the extent the Board shall
determine, in good faith, that such an adjustment (or substitution) is necessary
and appropriate. If this Section 8(a) applies and Section 8(c) also applies to
any event, Section 8(c) shall be applicable to such event, and this Section 8(a)
shall not be applicable.

         (b)      Liquidation or Dissolution. In the event of a proposed
liquidation or dissolution of the Company, the Board shall upon written notice
to the Participants provide that all then unexercised Options will (i) become
exercisable in full as of a specified time at least 10 business days prior to
the effective date of such liquidation or dissolution and (ii) terminate
effective upon such liquidation or dissolution, except to the extent exercised
before such effective date. The Board may specify the effect of a liquidation or
dissolution on any Restricted Stock Award or other Award granted under the Plan
at the time of the grant of such Award.

         (c)      Acquisition Events

                  (1)      Definition. An "Acquisition Event" shall mean: (a)
         any merger or consolidation of the Company with or into another entity
         as a result of which the Common Stock is converted into or exchanged
         for the right to receive cash, securities or other property or (b) any
         exchange of shares of the Company for cash, securities or other
         property pursuant to a statutory share exchange transaction.

                  (2)      Consequences of an Acquisition Event on Options. Upon
         the occurrence of an Acquisition Event, or the execution by the Company
         of any agreement with respect to an Acquisition Event, the Board shall
         provide that all outstanding Options shall be assumed, or equivalent
         options shall be substituted, by the acquiring or succeeding
         corporation (or an affiliate thereof). For purposes hereof, an Option
         shall be considered to be assumed if, following consummation of the
         Acquisition Event, the Option confers the right to purchase, for each
         share of Common Stock subject to the Option immediately prior to the
         consummation of the Acquisition Event, the consideration (whether cash,
         securities or other property) received as a result of the Acquisition
         Event by holders of Common Stock for each share of Common Stock held
         immediately prior to the consummation of the Acquisition Event (and if
         holders were offered a choice of consideration, the type of
         consideration chosen by the holders of a majority of the outstanding
         shares of Common Stock); provided, however, that if the consideration
         received as a result of the Acquisition Event is not solely common
         stock of the acquiring or succeeding corporation (or an affiliate
         thereof), the Company may, with the consent of the


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         acquiring or succeeding corporation, provide for the consideration to
         be received upon the exercise of Options to consist solely of common
         stock of the acquiring or succeeding corporation (or an affiliate
         thereof) equivalent in fair market value to the per share consideration
         received by holders of outstanding shares of Common Stock as a result
         of the Acquisition Event.

                  Notwithstanding the foregoing, if the acquiring or succeeding
         corporation (or an affiliate thereof) does not agree to assume, or
         substitute for, such Options, then the Board shall, upon written notice
         to the Participants, provide that all then unexercised Options will
         become exercisable in full as of a specified time prior to the
         Acquisition Event and will terminate immediately prior to the
         consummation of such Acquisition Event, except to the extent exercised
         by the Participants before the consummation of such Acquisition Event;
         provided, however, that in the event of an Acquisition Event under the
         terms of which holders of Common Stock will receive upon consummation
         thereof a cash payment for each share of Common Stock surrendered
         pursuant to such Acquisition Event (the "Acquisition Price"), then the
         Board may instead provide that all outstanding Options shall terminate
         upon consummation of such Acquisition Event and that each Participant
         shall receive, in exchange therefor, a cash payment equal to the amount
         (if any) by which (A) the Acquisition Price multiplied by the number of
         shares of Common Stock subject to such outstanding Options (whether or
         not then exercisable), exceeds (B) the aggregate exercise price of such
         Options.

                  (3)      Consequences of an Acquisition Event on Restricted
         Stock Awards. Upon the occurrence of an Acquisition Event, the
         repurchase and other rights of the Company under each outstanding
         Restricted Stock Award shall inure to the benefit of the Company's
         successor and shall apply to the cash, securities or other property
         which the Common Stock was converted into or exchanged for pursuant to
         such Acquisition Event in the same manner and to the same extent as
         they applied to the Common Stock subject to such Restricted Stock
         Award.

                  (4)      Consequences of an Acquisition Event on Other Awards.
         The Board shall specify the effect of an Acquisition Event on any other
         Award granted under the Plan at the time of the grant of such Award.

9.       General Provisions Applicable to Awards

         (a)      Transferability of Awards. Except as the Board may otherwise
determine or provide in an Award, Awards shall not be sold, assigned,
transferred, pledged or otherwise encumbered by the person to whom they are
granted, either voluntarily or by operation of law, except by will or the laws
of descent and distribution, and, during the life of the Participant, shall be
exercisable only by the Participant. References to a Participant, to the extent
relevant in the context, shall include references to authorized transferees.


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         (b)      Documentation. Each Award shall be evidenced by a written
instrument in such form as the Board shall determine. Each Award may contain
terms and conditions in addition to those set forth in the Plan.

         (c)      Board Discretion. Except as otherwise provided by the Plan,
each Award may be made alone or in addition or in relation to any other Award.
The terms of each Award need not be identical, and the Board need not treat
Participants uniformly.

         (d)      Termination of Status. The Board shall determine the effect on
an Award of the disability, death, retirement, authorized leave of absence or
other change in the employment or other status of a Participant and the extent
to which, and the period during which, the Participant, the Participant's legal
representative, conservator, guardian or Designated Beneficiary may exercise
rights under the Award.

         (e)      Withholding. Each Participant shall pay to the Company, or
make provision satisfactory to the Board for payment of, any taxes required by
law to be withheld in connection with Awards to such Participant no later than
the date of the event creating the tax liability. Except as the Board may
otherwise provide in an Award, when the Common Stock is registered under the
Exchange Act, Participants may satisfy such tax obligations in whole or in part
by delivery of shares of Common Stock, including shares retained from the Award
creating the tax obligation, valued at their Fair Market Value. The Company may,
to the extent permitted by law, deduct any such tax obligations from any payment
of any kind otherwise due to a Participant.

         (f)      Amendment of Award. The Board may amend, modify or terminate
any outstanding Award, including but not limited to, substituting therefor
another Award of the same or a different type, changing the date of exercise or
realization, and converting an Incentive Stock Option to a Nonstatutory Stock
Option, provided that the Participant's consent to such action shall be required
unless the Board determines that the action, taking into account any related
action, would not materially and adversely affect the Participant.

         (g)      Conditions on Delivery of Stock. The Company will not be
obligated to deliver any shares of Common Stock pursuant to the Plan or to
remove restrictions from shares previously delivered under the Plan until (i)
all conditions of the Award have been met or removed to the satisfaction of the
Company, (ii) in the opinion of the Company's counsel, all other legal matters
in connection with the issuance and delivery of such shares have been satisfied,
including any applicable securities laws and any applicable stock exchange or
stock market rules and regulations, and (iii) the Participant has executed and
delivered to the Company such representations or agreements as the Company may
consider appropriate to satisfy the requirements of any applicable laws, rules
or regulations.


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         (h)      Acceleration. The Board may at any time provide that any
Options shall become immediately exercisable in full or in part, that any
Restricted Stock Awards shall be free of restrictions in full or in part or that
any other Awards may become exercisable in full or in part or free of some or
all restrictions or conditions, or otherwise realizable in full or in part, as
the case may be.


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10.      Miscellaneous

         (a)      No Right To Employment or Other Status. No person shall have
any claim or right to be granted an Award, and the grant of an Award shall not
be construed as giving a Participant the right to continued employment or any
other relationship with the Company. The Company expressly reserves the right at
any time to dismiss or otherwise terminate its relationship with a Participant
free from any liability or claim under the Plan, except as expressly provided in
the applicable Award.

         (b)      No Rights As Stockholder. Subject to the provisions of the
applicable Award, no Participant or Designated Beneficiary shall have any rights
as a stockholder with respect to any shares of Common Stock to be distributed
with respect to an Award until becoming the record holder of such shares.
Notwithstanding the foregoing, in the event the Company effects a split of the
Common Stock by means of a stock dividend and the exercise price of and the
number of shares subject to such Option are adjusted as of the date of the
distribution of the dividend (rather than as of the record date for such
dividend), then an optionee who exercises an Option between the record date and
the distribution date for such stock dividend shall be entitled to receive, on
the distribution date, the stock dividend with respect to the shares of Common
Stock acquired upon such Option exercise, notwithstanding the fact that such
shares were not outstanding as of the close of business on the record date for
such stock dividend.

         (c)      Effective Date and Term of Plan. The Plan shall become
effective on the date on which it is adopted by the Board. No Awards shall be
granted under the Plan after the completion of ten years from the earlier of (i)
the date on which the Plan was adopted by the Board or (ii) the date the Plan
was approved by the Company's stockholders, but Awards previously granted may
extend beyond that date.

         (d)      Amendment of Plan. The Board may amend, suspend or terminate
the Plan or any portion thereof at any time.

         (e)      Governing Law. The provisions of the Plan and all Awards made
hereunder shall be governed by and interpreted in accordance with the laws of
the State of Delaware, without regard to any applicable conflicts of law.


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                       QUANTUM BRIDGE COMMUNICATIONS, INC.
                                    AMENDMENT
                                       TO
                        SECOND AMENDED AND RESTATED 1998
                        STOCK INCENTIVE PLAN, AS AMENDED

         AMENDMENT (this "Amendment"), dated as of September 20, 2000 to the
Quantum Bridge Communications, Inc. (the "Company") Second Amended and Restated
1998 Stock Incentive Plan, as amended (the "Plan").

                              W I T N E S S E T H:
                               -------------------

         WHEREAS, the Board of Directors of the Company voted by unanimous
written action of directors in lieu of a meeting, dated as of September 20,
2000, to increase the number of shares of common stock, $.001 par value per
share ("Common Stock") that may be issued under the Plan from 12,150,000 shares
to 13,650,000 shares.

         WHEREAS, the stockholders of the Company voted by written consent of
stockholders in lieu of a meeting, dated as of September 20, 2000, to increase
the number of shares of Common Stock that may be issued under the Plan from
12,150,000 shares to 13,650,000 shares.

         NOW, THEREFORE, subject to adjustment under Section 8 of the Plan,
awards may be made under the Plan for up to 13,650,000 shares of Common Stock.


                                             Quantum Bridge Communications, Inc.


                                             By: /s/ Anthony Zona
                                                 -------------------------------
                                                 Anthony Zona
                                                 President