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                                                                   EXHIBIT 4.04

THE SECURITIES REPRESENTED BY THIS CERTIFICATE (I) ARE SUBJECT TO THE
RESTRICTIONS ON TRANSFER AND OTHER TERMS CONTAINED IN A SUBSCRIPTION AGREEMENT
DATED [date of Subscription Agreement], BETWEEN THE COMPANY AND THE HOLDER OF
THIS WARRANT (A COPY OF WHICH IS AVAILABLE WITHOUT CHARGE FROM THE COMPANY), AND
(II) HAVE NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933 OR APPLICABLE
STATE SECURITIES LAWS AND MAY NOT BE TRANSFERRED, SOLD OR OTHERWISE DISPOSED OF
IN THE ABSENCE OF AN EFFECTIVE REGISTRATION STATEMENT WITH RESPECT TO THE
SECURITIES EVIDENCED BY THIS CERTIFICATE, FILED AND MADE EFFECTIVE UNDER THE
SECURITIES ACT OF 1933 AND SUCH APPLICABLE STATE SECURITIES LAWS, OR UNLESS THE
COMPANY RECEIVES AN OPINION OF COUNSEL SATISFACTORY TO THE COMPANY TO THE EFFECT
THAT REGISTRATION UNDER SUCH ACT AND SUCH APPLICABLE STATE SECURITIES LAWS IS
NOT REQUIRED.


                                 DSL.NET, INC.


                                   No. [__]

                    Warrant to Subscribe for [____________]

                              STOCK SUBSCRIPTION
                                    WARRANT

                               [________, 19___]

                        Not Transferable or Exercisable
                        -------------------------------
                    Except Upon Conditions Herein Specified
                    ---------------------------------------

     THIS CERTIFIES that for value received, [Name of Subscriber] (the
"Subscriber"), an individual with an address at [Address of Subscriber], is
entitled to subscribe for and purchase from DSL.NET, INC., a Delaware
corporation (the "Corporation"),  [____] shares (such number subject to
adjustment from time to time as hereinafter provided), of ________ Stock, $____
par value per share ("Warrant Stock"), of the Corporation, at the price of $____
per share (such price from time to subject to adjustment in accordance with
Section 4 hereof and hereinafter called the "Warrant Price"), at any time or
from to time during the period beginning on the date hereof and ending on the
first to occur of (i) the date five (5) years thereafter and (ii) the date on
which the Corporation consummates an initial public offering of its capital
stock registered under the Securities Act of 1933, as amended (the "Term of this
Warrant").

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     This Warrant is issued pursuant to, and is subject to, that certain
Subscription Agreement, dated as of [_______], 1998, by and between the
Corporation and the Subscriber (the "Subscription Agreement"), as the same may
be amended from time to time, copies of which may be inspected by the legal
holder hereof at the principal office of the Corporation. Capitalized terms not
otherwise defined herein shall have the meanings set forth in the Subscription
Agreement.

     SECTION 1.  Exercise of Warrant.  The rights represented by this Warrant
                 -------------------
may be exercised by the holder hereof, in whole at any time or in part from time
to time during the Term of this Warrant, but not as to a fractional share of
Warrant Stock, by the surrender of this Warrant  (properly endorsed)  at the
office of the Corporation, at 50 Washington Street, 7th Floor East, Norwalk,
Connecticut 06854 (or at such other agency or office of the Corporation in the
United States of America as it may designate by notice in writing to the holder
hereof at the address of such holder appearing on the books of the Corporation),
and by payment to the Corporation of the Warrant Price in cash or by certified
or cashier's check or wire transfer for each share being purchased.  In the
event of any exercise of the rights represented by this Warrant, a certificate
or certificates for the shares of Warrant Stock so purchased, registered in the
name of the holder, shall be delivered to the holder hereof within a reasonable
time, not exceeding twenty-five days, after the rights represented by this
Warrant shall have been so exercised; and, unless this Warrant has expired, a
new Warrant representing the number of shares, if any, with respect to which
this Warrant shall not then have been exercised shall also be issued to the
holder hereof within such time.  The person in whose name any certificate for
shares of Warrant Stock is issued upon exercise of this Warrant shall for all
purposes be deemed to have become the holder of record of such shares on the
date on which the Warrant was surrendered and payment of the Warrant Price and
any applicable taxes was made, irrespective of the date of delivery of such
certificate, except that, if the date of such surrender and payment is a date
when the stock transfer books of the Corporation are closed, such person shall
be deemed to have become the holder of such shares at the close of business on
the next succeeding date on which the stock transfer books are open.  The
Corporation shall pay any issue tax imposed on exercise of this Warrant for
Warrant Stock, provided, however, that the Subscriber shall be required to pay
               --------  -------
any and all taxes which may be payable in respect of any transfer involved in
the issuance and delivery of any certificate in a name other than that of the
Subscriber as reflected upon the books of the Company.

     Notwithstanding the foregoing or anything to the contrary herein, this
Warrant may be exercised only upon the delivery to the Company of any
certificates, legal opinions, or other documents reasonably requested by the
Company or its counsel to satisfy the Company and its counsel that the proposed
exercise of this Warrant may be effected without registration under the
Securities Act of 1933, as amended.  The Holder shall not be entitled to
exercise this Warrant, or any part hereof, unless and until such certificates,
legal opinions or other documents are reasonably acceptable to the Company and
its counsel.

     SECTION 2.  Covenants as to Warrant Stock.  The Corporation covenants and
                 -----------------------------
agrees that all shares of Warrant Stock that may be issued upon the exercise of
the rights represented by this Warrant will, upon issuance, be validly issued,
fully paid and nonassessable, and free from all taxes, liens and charges with
respect to the issue thereof.  The Corporation further covenants and agrees that
the Corporation will at all times have authorized and reserved, free from

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preemptive rights, a sufficient number of shares of its Warrant Stock to provide
for the exercise of the rights represented by this Warrant.  The Corporation
further covenants and agrees that if any shares of capital stock to be reserved
for the purpose of the issuance of shares upon the exercise of this Warrant
require registration with or approval of any governmental authority under any
Federal or State law before such shares may be validly issued or delivered upon
exercise, then the Corporation will in good faith and as expeditiously as
possible endeavor to secure such registration or approval, as the case may be.
If and so long as the Warrant Stock issuable upon the exercise of this Warrant
is listed on any national securities exchange, the Corporation will, if
permitted by the rules of such exchange, list and keep listed on such exchange,
upon official notice of issuance, all shares of such Warrant Stock issuable upon
exercise of this Warrant.

     SECTION 3.  Adjustment of Number of Shares.  Upon each adjustment of the
                 ------------------------------
Warrant Price as provided in Section 4, the holder of this Warrant shall
thereafter be entitled to purchase, at the Warrant Price resulting from such
adjustment, the number of shares (calculated to the nearest tenth of a share)
obtained by multiplying the Warrant Price in effect immediately prior to such
adjustment by the number of shares purchasable pursuant hereto immediately prior
to such adjustment and dividing the product thereof by the Warrant Price
resulting from such adjustment.

     SECTION 4.  Adjustment of Warrant Price.  The Warrant Price and the
                 ---------------------------
securities purchasable upon exercise of this Warrant shall be subject to
adjustment from time to time as follows:

     (i)    If, at any time during the Term of this Warrant, the number of
            shares of Warrant Stock outstanding is increased by a stock dividend
            payable in shares of Warrant Stock or by a subdivision or split-up
            of shares of Warrant Stock, then, following the record date fixed
            for the determination of holders of Warrant Stock entitled to
            receive such stock dividend, subdivision or split-up, the Warrant
            Price shall be appropriately decreased so that the number of shares
            of Warrant Stock issuable upon the exercise hereof shall be
            increased in proportion to such increase in outstanding shares.

     (ii)   If, at any time during the Term of this Warrant, the number of
            shares of Warrant Stock outstanding is decreased by a combination of
            the outstanding shares of Warrant Stock, then, following the record
            date for such combination, the Warrant Price shall appropriately
            increase so that the number of shares of Warrant Stock issuable upon
            the exercise hereof shall be decreased in proportion to such
            decrease in outstanding shares.

     (iii)  In case, at any time during the Term of this Warrant, of any capital
            reorganization, any reclassification of the stock of the Corporation
            (other than a change in par value or from par value to no par value
            or from no par value to par value or as a result of a stock dividend
            or subdivision, split-up or combination of shares), the
            consolidation or merger of the Corporation with or into another
            corporation (other than a consolidation or merger in which the
            Corporation is the continuing corporation and which does not result
            in any change in the Warrant Stock), or the

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            sale of all or substantially all the properties and assets of the
            Corporation as an entity to any other corporation, then this Warrant
            shall, after such reorganization, reclassification, consolidation,
            merger or sale, be exercisable for the kind and number of shares of
            stock or other securities or property of the Corporation or of the
            corporation resulting from such consolidation or surviving such
            merger or to which such properties and assets shall have been sold
            to which such holder would have been entitled if he had held the
            Warrant Stock issuable upon the exercise hereof immediately prior to
            such reorganization, reclassification, consolidation, merger or
            sale.

     (iv)   Whenever the Warrant Price shall be adjusted as provided in this
            Section 4, the Corporation shall prepare a statement showing the
            facts requiring such adjustment and the Warrant Price that shall be
            in effect after such adjustment. The Corporation shall cause a copy
            of such statement to be sent by mail, first class postage prepaid,
            to each holder of this Warrant at his address appearing on the
            Corporation's records. Where appropriate, such copy may be given in
            advance and may be included as part of the notice required to be
            mailed under the provisions of subsection (vi) of this Section 4.

     (v)    Adjustments made pursuant to clauses (i) and (ii) above shall be
            made on the date such dividend, subdivision, split-up, combination
            or distribution, as the case may be, is made, and shall become
            effective at the opening of business on the business day next
            following the record date for the determination of stockholders
            entitled to such dividend, subdivision, split-up, combination or
            distribution.

     (vi)   In the event the Corporation shall propose to take any action of the
            types described in clauses (i), (ii) or (iii) of this Section 4, the
            Corporation shall forward, at the same time and in the same manner,
            to the holder of this Warrant such notice, if any, which the
            Corporation shall give to the holders of capital stock of the
            Corporation. Failure to give such notice, or any defect therein,
            shall not affect the legality or validity of any such action.

     (vii)  In any case in which the provision of this Section 4 shall require
            that an adjustment shall become effective immediately after a record
            date for an event, the Corporation may defer until the occurrence of
            such event issuing to the holder of all or any part of this Warrant
            which is exercised after such record date and before the occurrence
            of such event the additional shares of capital stock issuable upon
            such exercise by reason of the adjustment required by such event
            over and above the shares of capital stock issuable upon such
            exercise before giving effect to such adjustment exercise; provided,
                                                                       --------
            however, that the Corporation shall deliver to such holder a due
            -------
            bill or other appropriate instrument evidencing such holder's right
            to receive such additional shares upon the occurrence of the event
            requiring such adjustment.

     (viii) The sale or other disposition of any Warrant Stock theretofore held
            in the treasury of the Corporation shall be deemed to be an issuance
            thereof.

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     SECTION 5.  Conversion of Preferred Stock.  In the event that the Warrant
                 -----------------------------
Stock is a class or type of security which is convertible into Common Stock of
the Corporation, as now or as hereafter constituted ("Common Stock"), then, at
such time as there are no outstanding shares of Warrant Stock (due to conversion
into Common Stock or otherwise), this Warrant, without any action of the
Corporation, shall automatically be converted into a warrant to purchase such
number of shares of Common Stock equal to the number of shares of Common Stock
issuable upon conversion of the shares of Warrant Stock for which this Warrant
could have been exercised immediately prior to the time that the Warrant Stock
ceased to be outstanding.  Thereafter, all references to (i) "Warrant Stock"
shall mean "Common Stock", and (ii) "Warrant Shares" shall refer to shares of
"Common Stock" rather than shares of "Warrant Stock."  Notwithstanding any
provisions herein to the contrary, the Corporation agrees and covenants to make
and deliver as soon as practicable upon the occurrence of such conversion, in
place of this Warrant, a new Warrant of like tenor and representing the right to
purchase the number of shares of Common Stock into which this Warrant will then
be exercisable; provided, however, that the Corporation shall not be required to
                --------  -------
issue a new Warrant if this Warrant has been exercised or expired.

     SECTION 6.  No Stockholder Rights.  Except as specifically provided for in
                 ---------------------
this Warrant, this Warrant shall not entitle the holder hereof to any voting
rights or other rights as a stockholder of the Corporation.

     SECTION 7.  Transfer of Warrant.  Subject to the provisions of the
                 -------------------
Subscription Agreement, this Warrant and all rights hereunder are transferable,
in whole or in part, but only to a person or entity controlling, controlled by,
or under common control with, the holder hereof including the partners of the
holder, at the agency or office of the Corporation referred to in Section 1, by
the holder hereof in person or by duly authorized attorney, upon surrender of
this Warrant properly endorsed.  Each taker and holder of this Warrant, by
taking or holding the same, consents and agrees that this Warrant, when
endorsed, in blank, shall be deemed negotiable, and when so endorsed the holder
hereof may be treated by the Corporation and all other persons dealing with this
Warrant as the absolute owner hereof for any purposes and as the person entitled
to exercise the rights represented by this Warrant, or to the transfer hereof on
the books of the Corporation, any notice to the contrary notwithstanding; but
until such transfer on such books, the Corporation may treat the registered
holder hereof as the owner hereof for all purposes.

     SECTION 8.  Exchange of Warrant.  This Warrant is exchangeable, upon
                 -------------------
surrender hereof by the holder hereof at the office or agency of the Corporation
designated in Section 1 hereof, for new Warrants of like tenor representing in
the aggregate the right to subscribe for and purchase the number of shares which
may be subscribed for and purchased hereunder, each of such new Warrants to
represent the right to subscribe for and purchase such number of shares as shall
be designated by said holder hereof at the time of such surrender.

     SECTION 9.  Lost, Stolen, Mutilated or Destroyed Warrant.  If this Warrant
                 --------------------------------------------
is lost, stolen, mutilated or destroyed, the Corporation may, on such terms as
to indemnity or otherwise as it may in its discretion impose (which shall, in
the case of a mutilated Warrant, include the

                                       5
<PAGE>

surrender thereof), issue a new Warrant of like denomination and tenor as the
Warrant so lost, stolen, mutilated or destroyed. Any such new Warrant shall
constitute an original contractual obligation of the Corporation, whether or not
the allegedly lost, stolen, mutilated or destroyed Warrant shall be at any time
enforceable by anyone.

     SECTION 10.  Fractional Shares.  Fractional shares shall not be issued upon
                  -----------------
the exercise of this Warrant, but in any case where the Subscriber would, except
for the provisions of this Section 10, be entitled under the terms hereof to
receive a fractional share upon the complete exercise of this Warrant, the
Corporation shall, upon the exercise of this Warrant for the largest number of
whole shares then called for, cancel this Warrant and pay a sum in cash equal to
the value of such fractional share (determined in such reasonable manner as may
be prescribed in good faith by the Board of Directors of the Corporation).

     SECTION 11.  Information by Holder.  Each Subscriber shall furnish to the
                  ---------------------
Corporation such information regarding such Subscriber as the Corporation may
reasonably request in writing and as shall be reasonably required in connection
with any registration, qualification or compliance.

     SECTION 12.  Law Governing.  This Warrant shall be governed by, and
                  -------------
construed and enforced in accordance with, the laws of the State of Delaware,
without giving effect to the principles of conflicts of law thereof.

     SECTION 13.  Miscellaneous.
                  -------------

     (a) This Warrant and any provision hereof may be changed, waived,
discharged or terminated only by an instrument in writing signed by the party
(or any predecessor in interest thereof) against which enforcement of the same
is sought.  The headings in this Warrant are for purposes of reference only and
shall not affect the meaning or construction of any of the provisions hereof.

     (b) Any provision of this Warrant which is prohibited or unenforceable in
any jurisdiction shall, as to such jurisdiction, be ineffective to the extent of
such prohibition or unenforceability without invalidating the remaining
provisions hereof, and any such prohibition or  unenforceability in any
jurisdiction shall not invalidate or render unenforceable such provision in any
other jurisdiction.

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     IN WITNESS WHEREOF, DSL.NET, INC. has caused this Warrant to be executed by
its duly authorized officer, and this Warrant to be dated [______], 1998.

                              DSL.NET, INC.



                              By:
                                 --------------------------------------
                              Name:
                              Title:



ATTEST:



Name:

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