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                                                                     EXHIBIT 4.1

                            ENTERASYS NETWORKS, INC.
                           2004 EQUITY INCENTIVE PLAN

1.    DEFINED TERMS

      Exhibit A, which is incorporated by reference, defines the terms used in
the Plan and sets forth certain operational rules related to those terms.

2.    PURPOSE

      The Plan has been established to advance the interests of the Company by
providing for the grant to Participants of Stock-based Awards and
performance-based cash Awards.

3.    ADMINISTRATION

      The Administrator has discretionary authority, subject only to the express
provisions of the Plan, to interpret the Plan; determine eligibility for and
grant Awards; determine, modify or waive the terms and conditions of any Award;
prescribe forms, rules and procedures; and otherwise do all things necessary to
carry out the purposes of the Plan. In the case of any Award intended to be
eligible for the performance-based compensation exception under Section 162(m),
the Administrator will exercise its discretion consistent with qualifying the
Award for that exception. Determinations of the Administrator made under the
Plan will be conclusive and will bind all parties.

4.    LIMITS ON AWARDS UNDER THE PLAN

      (a)   NUMBER OF SHARES. A maximum of 15,000,000 shares of Stock, less the
combined number of shares issued and shares available for issuance from time to
time under the Enterasys Networks, Inc. 2002 Employee Stock Purchase Plan (the
"2002 ESPP"), may be delivered in satisfaction of Awards under the Plan. Subject
to such overall maximum, up to 14,000,000 shares of Stock, less the combined
number of shares issued and shares available for issuance from time to time
under the 2002 ESPP, may be issued upon the exercise of ISOs and up to
14,000,000 shares of Stock, less the combined number of shares issued and shares
available for issuance from time to time under the 2002 ESPP, may be issued upon
the exercise of Stock Options that are not ISOs. To the extent consistent with
the requirements of Section 422 of the Code and regulations thereunder, and with
other applicable legal requirements (including applicable stock exchange
requirements), Stock issued under awards of an acquired company that are assumed
in connection with the acquisition, or under awards issued in substitution for
any such acquired-company awards, shall not reduce the number of shares
available for Awards under the Plan.

      (b)   TYPE OF SHARES. Stock delivered by the Company under the Plan may be
authorized but unissued Stock or previously issued Stock acquired by the
Company. No fractional shares of Stock will be delivered under the Plan.

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      (c)   SECTION 162(m) LIMITS. The maximum number of shares of Stock for
which Stock Options may be granted to any person in any calendar year and the
maximum number of shares of Stock subject to SARs granted to any person in any
calendar year will each be 2,000,000. The maximum number of shares subject to
other Awards granted to any person in any calendar year will be 2,000,000
shares. The maximum amount payable to any person in any calendar year under Cash
Awards is $5,000,000. The foregoing provisions will be construed in a manner
consistent with Section 162(m).

      (d)   OTHER LIMITS.

            (1) No more than 1,500,000 shares of Stock may be granted as, or
made subject to, Awards of Restricted Stock or Awards of Restricted Stock Units
that are scheduled to vest more rapidly than ratably over a 4-year period or
based on performance criteria that do not extend for at least 2 years. No shares
may be granted as, or made subject to, Awards of Restricted Stock or Awards of
Restricted Stock Units that are scheduled to vest in a period of less than one
year. The preceding limitations shall not be construed to limit acceleration of
vesting on account of death, disability, or retirement or by reason of Section
7, or the grant of awards with different terms that are in substitution for
awards granted by another company that is acquired by or merged with or into the
Company or a subsidiary of the Company or by an affiliate thereof.

            (2) The maximum number of shares of Stock for which Awards may be
made to a non-Employee Director in any calendar year is an aggregate of 100,000
shares.

            (3) The total aggregate number of shares of Stock subject to Awards
granted during any one calendar year may not exceed 5% of the Company's total
aggregate shares of issued and outstanding Stock as of the last day of the
calendar year.

5.    ELIGIBILITY AND PARTICIPATION

      The Administrator will select Participants from among those key Employees
and directors of, and consultants and advisors to, the Company or its Affiliates
who, in the opinion of the Administrator, are in a position to make a
significant contribution to the success of the Company and its Affiliates.
Eligibility for ISOs is limited to employees of the Company or of a "parent
corporation" or "subsidiary corporation" of the Company as those terms are
defined in Section 424 of the Code.

6.    RULES APPLICABLE TO AWARDS

      (a)   ALL AWARDS

            (1) AWARD PROVISIONS. The Administrator will determine the terms of
all Awards, subject to the limitations provided herein.

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            (2) TRANSFERABILITY. Neither ISOs nor, except as the Administrator
otherwise expressly provides, other Awards may be transferred other than by will
or by the laws of descent and distribution, and during a Participant's lifetime
ISOs (and, except as the Administrator otherwise expressly provides, other
non-transferable Awards requiring exercise) may be exercised only by the
Participant.

            (3) VESTING, ETC. The Administrator may determine the time or times
at which an Award will vest or become exercisable and the terms on which an
Award requiring exercise will remain exercisable during or following cessation
of Employment. Without limiting the foregoing, the Administrator may at any time
accelerate the vesting or exercisability of an Award, regardless of any adverse
or potentially adverse tax consequences resulting from such acceleration. Unless
the Administrator expressly provides otherwise, immediately upon the cessation
of the Participant's Employment an Award requiring exercise will cease to be
exercisable and will terminate, and all other Awards to the extent not already
vested will be forfeited, except that:

            (A) subject to (B) and (C) below, all Stock Options and SARs held by
      the Participant or the Participant's permitted transferee, if any,
      immediately prior to the cessation of the Participant's Employment, to the
      extent then exercisable, will remain exercisable for the lesser of (i) a
      period of three months or (ii) the period ending on the latest date on
      which such Stock Option or SAR could have been exercised without regard to
      this Section 6(a)(3), and will thereupon terminate;

            (B) all Stock Options and SARs held by a Participant or the
      Participant's permitted transferee, if any, immediately prior to the
      Participant's death, to the extent then exercisable, will remain
      exercisable for the lesser of (i) the one year period ending with the
      first anniversary of the Participant's death or (ii) the period ending on
      the latest date on which such Stock Option or SAR could have been
      exercised without regard to this Section 6(a)(3), and will thereupon
      terminate; and

            (C) all Stock Options and SARs held by a Participant or the
      Participant's permitted transferee, if any, immediately prior to the
      cessation of the Participant's Employment will immediately terminate upon
      such cessation if the Administrator in its sole discretion determines that
      such cessation of Employment has resulted for reasons which cast such
      discredit on the Participant as to justify immediate termination of the
      Award.

            (4) TAXES. The Administrator will make such provision for the
withholding of taxes as it deems necessary. The Administrator may, but need not,
hold back shares of Stock from an Award or permit a Participant to tender
previously owned shares of Stock in satisfaction of tax withholding requirements
(but not in excess of the minimum withholding required by law).

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            (5) DIVIDEND EQUIVALENTS, ETC. The Administrator may provide for the
payment of amounts in lieu of cash dividends or other cash distributions with
respect to Stock subject to an Award.

            (6) RIGHTS LIMITED. Nothing in the Plan will be construed as giving
any person the right to continued employment or service with the Company or its
Affiliates, or any rights as a stockholder except as to shares of Stock actually
issued under the Plan. The loss of existing or potential profit in Awards will
not constitute an element of damages in the event of termination of employment
or service for any reason, even if the termination is in violation of an
obligation of the Company or Affiliate to the Participant.

            (7) SECTION 162(m). This Section 6(a)(7) applies to any Performance
Award intended to qualify as performance-based for the purposes of Section
162(m) other than a Stock Option or SAR. In the case of any Performance Award to
which this Section 6(a)(7) applies, the Plan and such Award will be construed to
the maximum extent permitted by law in a manner consistent with qualifying the
Award for such exception. With respect to such Performance Awards, the
Administrator will preestablish, in writing, one or more specific Performance
Criteria no later than 90 days after the commencement of the period to which the
performance relates (or at such earlier time as is required to qualify the Award
as performance-based under Section 162(m)). The Performance Criteria so
established shall serve as a condition to the grant, vesting or payment of the
Performance Award, as determined by the Administrator. Prior to grant, vesting
or payment of the Performance Award, as the case may be, the Administrator will
certify whether the Performance Criteria have been attained and such
determination will be final and conclusive. If the Performance Criteria with
respect to the Award are not attained, no other Award will be provided in
substitution of the Performance Award. No Performance Award to which this
Section 6(a)(7) applies may be granted after the first meeting of the
stockholders of the Company held in 2009 until the performance measures
specified under the definition of "Performance Criteria" (as the same may be
amended) have been resubmitted to and reapproved by the stockholders of the
Company in accordance with the requirements of Section 162(m) of the Code,
unless such grant is made contingent upon such approval.

            (8) NON-U.S. AWARDS. Awards under the Plan may be granted to any
eligible person regardless of the jurisdiction in which he or she works or
resides. Notwithstanding the foregoing, the Administrator in its discretion may
establish one or more separate subplans or programs under the Plan for the grant
of Awards to eligible persons in a specified jurisdiction or jurisdictions and
may include in any such subplan or program such special rules as it determines.

            (9) TERM OF PLAN. No Award may be granted under the Plan after
February 11, 2014, but Awards previously granted may extend beyond that date.

      (b)   AWARDS REQUIRING EXERCISE

            (1) TIME AND MANNER OF EXERCISE. Unless the Administrator expressly
provides otherwise, an Award requiring exercise by the holder will not be deemed
to have been exercised until the Administrator receives a notice of exercise (in
form acceptable to the

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Administrator) signed by the appropriate person and accompanied by any payment
required under the Award. If the Award is exercised by any person other than the
Participant, the Administrator may require satisfactory evidence that the person
exercising the Award has the right to do so.

            (2) EXERCISE PRICE. The exercise price of an Award requiring
exercise will not be less than the fair market value of the Stock subject to the
Award, determined as of the date of grant. No Award requiring exercise, once
granted, may be repriced other than in accordance with the stockholder approval
requirements of the New York Stock Exchange.

            (3) PAYMENT OF EXERCISE PRICE. Where the exercise of an Award is to
be accompanied by or otherwise requires payment, such payment shall be made by
cash or check acceptable to the Administrator, or, if so permitted by the
Administrator and if legally permissible, (a) through the delivery of shares of
Stock that have been outstanding for at least six months (unless the
Administrator approves a shorter period) and that have a fair market value equal
to the exercise price, (b) by delivery to the Company of a promissory note of
the person exercising the Award, payable on such terms as are specified by the
Administrator, (c) through a broker-assisted exercise program acceptable to the
Administrator, (d) by other means acceptable to the Administrator, or (e) by any
combination of the foregoing permissible forms of payment. The delivery of
shares in payment of the exercise price under clause (a) above may be
accomplished either by actual delivery or by constructive delivery through
attestation of ownership, subject to such rules as the Administrator may
prescribe.

            (4) EXPIRATION OF AWARD. All Awards requiring exercise, to the
extent not previously exercised, forfeited, canceled or otherwise terminated,
shall expire not later than seven years from the date of grant.

      (c)   AWARDS NOT REQUIRING EXERCISE

      Awards of Restricted Stock and Unrestricted Stock may be made in exchange
for such lawful consideration, including services, as the Administrator
determines.

7.    EFFECT OF CERTAIN TRANSACTIONS

      (a)   MERGERS, ETC.

            (1) COVERED TRANSACTIONS. Except as otherwise provided in an Award,
in the event of a Covered Transaction in which there is an acquiring or
surviving entity, the Administrator may provide for the assumption of some or
all outstanding Awards, or for the grant of new awards in substitution therefor,
by the acquiror or survivor or an affiliate of the acquiror or survivor, in each
case on such terms and subject to such conditions as the Administrator
determines. In the event of a Covered Transaction (whether or not there is an
acquiring or surviving entity) where there is no such assumption or
substitution, except as otherwise provided in the Award each Stock Option, SAR
and other Award requiring exercise

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will become fully exercisable, and the delivery of shares of Stock issuable
under each outstanding Award of Restricted Stock Units will be accelerated and
such shares will be issued, prior to the Covered Transaction, in each case on a
basis that gives the holder of the Award a reasonable opportunity, as determined
by the Administrator, following exercise of the Award or the issuance of the
shares, as the case may be, to participate as a stockholder in the Covered
Transaction, and the Award will terminate upon consummation of the Covered
Transaction. Any shares of Stock issued pursuant to the preceding sentence in
satisfaction of an Award may, in the discretion of the Administrator, contain
such restrictions, if any, as the Administrator deems appropriate to reflect any
performance or other vesting condition to which the Award was subject. In the
case of Restricted Stock, the Administrator may require that any amounts
delivered, exchanged or otherwise paid in respect of such Stock in connection
with the Covered Transaction be placed in escrow or otherwise made subject to
such restrictions as the Administrator deems appropriate to carry out the intent
of the Plan.

      (b)   CHANGES IN AND DISTRIBUTIONS WITH RESPECT TO THE STOCK

            (1) BASIC ADJUSTMENT PROVISIONS. In the event of a stock dividend,
stock split (including reverse stock split) or combination of shares,
recapitalization or other change in the Company's capital structure, the
Administrator will make appropriate adjustments to the maximum number of shares
specified in Section 4(a) that may be delivered under the Plan, to the maximum
number of shares specified in Section 4(a) that may be issued upon the exercise
of ISOs, to the maximum number of shares specified in Section 4(a) that may be
issued with respect to Stock Options that are not ISOs, and to the maximum share
limits described in Section 4(c) and 4(d), and will also make appropriate
adjustments to the number and kind of shares of stock or securities subject to
Awards then outstanding or subsequently granted, any exercise prices relating to
Awards and any other provision of Awards affected by such change.

            (2) CERTAIN OTHER ADJUSTMENTS. To the extent consistent with
qualification of ISOs under Section 422 of the Code and with the
performance-based compensation rules of Section 162(m), where applicable, the
Administrator may also make adjustments of the type described in Section 7(b)(1)
to take into account distributions to stockholders other than those provided for
in Section 7(a) and 7(b)(1), or any other event, if the Administrator determines
that adjustments are appropriate to avoid distortion in the operation of the
Plan and to preserve the value of Awards made hereunder.

            (3) CONTINUING APPLICATION OF PLAN TERMS. References in the Plan to
shares of Stock will be construed to include any stock or securities resulting
from an adjustment pursuant to this Section 7.

8.    LEGAL CONDITIONS ON DELIVERY OF STOCK

      The Company will not be obligated to deliver any shares of Stock pursuant
to the Plan or to remove any restriction from shares of Stock previously
delivered under the Plan until: (i) the Company is satisfied that all legal
matters in connection with the issuance and delivery of such

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shares have been addressed and resolved; (ii) if the outstanding Stock is at the
time of delivery listed on any stock exchange or national market system, the
shares to be delivered have been listed or authorized to be listed on such
exchange or system upon official notice of issuance; and (iii) all conditions of
the Award have been satisfied or waived. If the sale of Stock has not been
registered under the Securities Act of 1933, as amended, the Company may
require, as a condition to exercise of the Award, such representations or
agreements as counsel for the Company may consider appropriate to avoid
violation of such Act. The Company may require that certificates evidencing
Stock issued under the Plan bear an appropriate legend reflecting any
restriction on transfer applicable to such Stock, and the Company may hold the
certificates pending lapse of the applicable restrictions.

9.    AMENDMENT AND TERMINATION

      The Administrator may at any time or times amend the Plan or any
outstanding Award for any purpose which may at the time be permitted by law, and
may at any time terminate the Plan as to any future grants of Awards; provided,
that except as otherwise expressly provided in the Plan the Administrator may
not, without the Participant's consent, alter the terms of an Award so as to
affect adversely a Participant's rights under the Award, unless the
Administrator expressly reserved the right to do so at the time of the Award.
Amendments to the Plan shall be conditioned upon stockholder approval only to
the extent, if any, such approval is required by law (including the Code and
applicable stock exchange requirements), as determined by the Administrator.

10.   OTHER COMPENSATION ARRANGEMENTS

      The existence of the Plan or the grant of any Award will not in any way
affect the Company's right to Award a person bonuses or other compensation in
addition to Awards under the Plan.

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EXHIBIT A

                               DEFINITION OF TERMS

      The following terms, when used in the Plan, will have the meanings and be
subject to the provisions set forth below:

      "ADMINISTRATOR": The Compensation Committee, except that the Compensation
Committee may delegate (i) to one or more of its members such of its duties,
powers and responsibilities as it may determine; (ii) to one or more officers of
the Company the authority to grant rights or options to the extent permitted by
Section 157(c) of the Delaware General Corporation Law; (iii) to one or more
officers of the Company the authority to allocate other Awards among such
persons (other than officers of the Company) eligible to receive Awards under
the Plan as such delegated officer or officers determine consistent with such
delegation; provided, that with respect to any delegation described in this
clause (iii) the Compensation Committee (or a properly delegated member or
members of such Committee) shall have authorized the issuance of a specified
number of shares of Stock under such Awards and shall have specified the
consideration, if any, to be paid therefor; and (iv) to such Employees or other
persons as it determines such ministerial tasks as it deems appropriate. In the
event of any delegation described in the preceding sentence, the term
"Administrator" shall include the person or persons so delegated to the extent
of such delegation.

      "AFFILIATE": Any corporation or other entity owning, directly or
indirectly, 50% or more of the outstanding Stock of the Company, or in which the
Company or any such corporation or other entity owns, directly or indirectly,
50% of the outstanding capital stock (determined by aggregate voting rights) or
other voting interests.

      "AWARD": Any or a combination of the following:

            (i)   Stock Options.

            (ii)  SARs.

            (iii) Restricted Stock.

            (iv)  Stock Units, including Restricted Stock Units.

            (v)   Performance Awards.

            (vi)  Cash Awards

            (vii) Awards (other than Awards described in (i), (ii), (iii), (iv),
      (v) or (vi) above) that are convertible into or otherwise based on Stock.

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      "BOARD": The Board of Directors of the Company.

      "CASH AWARD" means an Award denominated in cash.

      "CODE": The U.S. Internal Revenue Code of 1986 as from time to time
amended and in effect, or any successor statute as from time to time in effect.

      "COMPENSATION COMMITTEE": The Compensation Committee of the Board.

      "COMPANY": Enterasys Networks, Inc.

      "COVERED TRANSACTION": Any of (i) a consolidation, merger, or similar
transaction or series of related transactions in which the Company is not the
surviving corporation or which results in the acquisition of all or
substantially all of the Company's then outstanding common stock by a single
person or entity or by a group of persons and/or entities acting in concert,
(ii) a sale or transfer of all or substantially all the Company's assets, or
(iii) a dissolution or liquidation of the Company. Where a Covered Transaction
involves a tender offer that is reasonably expected to be followed by a merger
described in clause (i) (as determined by the Administrator), the Covered
Transaction shall be deemed to have occurred upon consummation of the tender
offer.

      "EMPLOYEE": Any person who is employed by the Company or an Affiliate.

      "EMPLOYMENT": A Participant's employment or other service relationship
with the Company and its Affiliates. Employment will be deemed to continue,
unless the Administrator expressly provides otherwise, so long as the
Participant is employed by, or otherwise is providing services in a capacity
described in Section 5 to the Company or its Affiliates. If a Participant's
employment or other service relationship is with an Affiliate and that entity
ceases to be an Affiliate, the Participant's Employment will be deemed to have
terminated when the entity ceases to be an Affiliate unless the Participant
transfers Employment to the Company or its remaining Affiliates.

      "ISO": A Stock Option intended to be an "incentive stock option" within
the meaning of Section 422 of the Code. Each option granted pursuant to the Plan
will be treated as providing by its terms that it is to be a non-incentive
option unless, as of the date of grant, it is expressly designated as an ISO.

      "PARTICIPANT": A person who is granted an Award under the Plan.

      "PERFORMANCE AWARD": An Award subject to Performance Criteria. The
Committee in its discretion may grant Performance Awards that are intended to
qualify for the performance-based compensation exception under Section 162(m)
and Performance Awards that are not intended so to qualify.

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      "PERFORMANCE CRITERIA": Specified criteria, other than the mere
performance of services or the mere passage of time, the satisfaction of which
is a condition for the grant, exercisability, vesting or full enjoyment of an
Award. For purposes of Awards that are intended to qualify for the
performance-based compensation exception under Section 162(m), a Performance
Criterion will mean an objectively determinable measure of performance relating
to any or any combination of the following (measured either absolutely or by
reference to an index or indices and determined either on a consolidated basis
or, as the context permits, on a separate entity, divisional, subsidiary, line
of business, project or geographical basis or in combinations thereof): (a)
sales; revenues; assets; expenses; earnings before or after deduction for all or
any portion of interest, taxes, depreciation or amortization, whether or not on
a continuing operations or an aggregate or per share basis; return on equity,
investment, capital or assets; inventory level or turns; one or more operating
ratios; borrowing levels, leverage ratios or credit rating; market share;
capital expenditures; cash flow; stock price; stockholder return; or any
combination of the foregoing; or (b) acquisitions and divestitures (in whole or
in part); joint ventures and strategic alliances; spin-offs, split-ups and the
like; reorganizations; recapitalizations, restructurings, financings (issuance
of debt or equity) and refinancings; transactions that would constitute a change
of control; or any combination of the foregoing. A qualified performance measure
and targets with respect thereto determined by the Committee need not be based
upon an increase, a positive or improved result or avoidance of loss. To the
extent consistent with the requirements for satisfying the performance-based
compensation exception under Section 162(m), the Administrator may provide in
the case of any Award intended to qualify for such exception that one or more of
the Performance Criteria applicable to such Award will be adjusted in an
objectively determinable manner to reflect events (for example, but without
limitation, acquisitions or dispositions) occurring during the performance
period that affect the applicable Performance Criterion or Criteria.

      "PLAN": The Enterasys Networks, Inc. 2004 Equity Incentive Plan as from
time to time amended and in effect.

      "RESTRICTED STOCK": An Award of Stock for so long as the Stock remains
subject to restrictions requiring that it be redelivered or offered for sale to
the Company if specified performance or other vesting conditions are not
satisfied.

      "RESTRICTED STOCK UNIT": A Stock Unit that is, or as to which the delivery
of Stock or cash in lieu of Stock is, subject to the satisfaction of specified
performance or other vesting conditions.

      "SECTION 162(m)": Section 162(m) of the Code.

      "SARs": Rights entitling the holder upon exercise to receive cash or
Stock, as the Administrator determines, equal to a function (determined by the
Administrator using such factors as it deems appropriate) of the amount by which
the Stock has appreciated in value since the date of the Award.

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      "STOCK": Common Stock of the Company, par value $.01 per share.

      "STOCK UNIT": An unfunded and unsecured promise, denominated in shares of
Stock, to deliver Stock or cash measured by the value of Stock in the future.

      "STOCK OPTIONS": Options entitling the recipient to acquire shares of
Stock upon payment of the exercise price.


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