EXHIBIT 10.01
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                            THIRD AMENDMENT AGREEMENT
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           THIRD AMENDMENT AGREEMENT (this "AMENDMENT AGREEMENT") dated as of
April 2, 2001 by and between DSL.net, Inc. (the "BORROWER") and Fleet National
Bank (the "BANK"), amending a certain Credit Agreement by and between the
Borrower and the Bank dated as of May 12, 1999, as amended by that Amendment and
Waiver Agreement dated as of June 12, 2000 and a Second Amendment Agreement
dated as of July 21, 2000 (as amended, the "CREDIT AGREEMENT").

                               W I T N E S S E T H
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           WHEREAS, pursuant to the terms of the Credit Agreement, the Bank has
made loans to the Borrower; and

           WHEREAS, the Borrower has requested that the Bank amend the Credit
Agreement; and

           WHEREAS, the Bank is willing to amend certain terms and conditions of
the Credit Agreement on the terms and conditions set forth herein.

           NOW, THEREFORE, for good and valuable consideration, the receipt and
sufficiency of which are hereby acknowledged, the parties hereto agree as
follows:

           Section 1. Definitions. Capitalized terms used herein without
definition that are defined in the Credit Agreement shall have the same meanings
herein as therein.

           Section 2. Ratification of Existing Agreements. All of the Borrower's
obligations and liabilities to the Bank as evidenced by or otherwise arising
under the Credit Agreement, the Note and the other Loan Documents, except as
otherwise expressly modified in this Amendment Agreement upon the terms set
forth herein, are, by the Borrower's execution of this Amendment Agreement,
ratified and confirmed in all respects. In addition, by the Borrower's execution
of this Amendment Agreement, the Borrower represents and warrants that no
counterclaim, right of set-off or defense of any kind exists or is outstanding
with respect to such obligations and liabilities.

           Section 3. Representations and Warranties. All of the representations
and warranties made by the Borrower in the Credit Agreement, the Note and the
other Loan Documents are true and correct on the date hereof as if made on and
as of the date hereof, except to the extent that any of such representations and
warranties expressly relate by their terms to a prior date and for matters
previously disclosed to the Bank in writing.

           Section 4. Conditions Precedent. The effectiveness of the amendments
contemplated hereby shall be subject to the satisfaction on or before the date
hereof of each of the following conditions precedent:
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                     (a) Representations and Warranties. All of the
           representations and warranties made by the Borrower herein, whether
           directly or incorporated by reference, shall be true and correct on
           the date hereof, except as provided in Section 3 hereof.

                     (b) Performance; No Event of Default. The Borrower shall
           have performed and complied in all material respects with all terms
           and conditions herein required to be performed or complied with by it
           prior to or at the time hereof, and there shall exist no Event of
           Default or condition which, with either or both the giving of notice
           of the lapse of time, would result in an Event of Default upon the
           execution and delivery of this Amendment Agreement.

                     (c) Corporate Action. All requisite corporate action
           necessary for the valid execution, delivery and performance by the
           Borrower of this Amendment Agreement and all other instruments and
           documents delivered by the Borrower in connection therewith shall
           have been duly and effectively taken.

                     (d) Delivery. The parties hereto shall have executed and
           delivered this Amendment Agreement, in form and substance
           satisfactory to the Bank.

                     (e) Fees and Expenses. The Borrower shall have paid to the
           Bank all reasonable fees and expenses incurred by the Bank in
           connection with this Amendment Agreement, the Credit Agreement and
           the other Loan Documents.

           Section 5. Amendments to the Credit Agreement.

                     5.1.      AMENDMENTS TO Section 1.  Section 1 of the Credit
Agreement is hereby as follows:

                     (a)   The definition of "Maturity Date" appearing in
                           Section 1 of the Credit Agreement is hereby amended
                           in its entirety to read as follows:

                           "Maturity Date: August 1, 2001."

                     (b)   The definition of "Security Documents appearing in
                           Section 1 of the Credit Agreement is hereby amended
                           by adding "and the Pledge Agreement" after "Bank" in
                           the second line of such definition.

                     (c)   The following new definitions are hereby added to
                           Section 1 in their proper alphabetical order to read
                           as follows:


                           "Pledge Agreement: The Pledge Agreement dated as of
                           the Third Amendment Effective Date made by the
                           Borrower to the Bank."

                           "Third Amendment Effective Date: April 2, 2001."

                     5.2.      AMENDMENT  TO  Section 7.2(a).  Section  2.2(b)
of the Credit Agreement is hereby amended in its entirety to read as follows:
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                               "(b) On the Conversion Date the aggregate
           outstanding principal amount of the Loans was $4,278,563.26. Since
           such date the Borrower has made mandatory principal installment
           payments in the aggregate amount of $1,222,446.60. As a result, the
           aggregate outstanding principal balance of the Loans is
           $3,056,116.66. Accordingly, the Borrower hereby absolutely and
           unconditionally promises to pay to the Bank the remaining principal
           amount of the Loans as follows: (i) one (1) principal payment
           installment in the amount of 122,244.66 due and payable on May 1,
           2001 and (ii) thereafter, three (3) consecutive equal monthly
           installments of $977,957.33 each, such installments to be due and
           payable on the first (1st) day of each calendar month commencing on
           June 1, 2001; provided, that the outstanding principal amount of the
           Loans, together with all interest accrued thereon and all fees and
           expenses incurred by the Bank in connection therewith, shall be due
           and payable on the Maturity Date."

                     5.3.      AMENDMENT TO Section 7.3.  Section 7.3 of the
Credit Agreement is hereby amended in its entirety to read as follows

                     "7.3  INTENTIONALLY OMITTED."

           Section 6. Additional Covenants. Without any prejudice or impairment
whatsoever to any of the Bank's rights and remedies contained in the Credit
Agreement and the covenants contained therein, the Note or in any of the other
Loan Documents, the Borrower additionally covenants and agrees with the Bank as
follows:

                     (a) The Borrower shall comply and continue to comply with
           all of the terms, covenants and provisions contained in the Credit
           Agreement, the Note and the other Loan Documents, except as such
           terms, covenants and provisions are expressly modified by this
           Amendment Agreement upon the terms set forth herein.

                     (b) The Borrower will provide to the Bank such financial
           information as the Bank may reasonably request from time to time and
           at the Borrower's expense.

                     (c) The Borrower shall at any time or from time to time
           execute and deliver such further instruments, and take such further
           action as the Bank may reasonably request, in each case further to
           effect the purposes of this Amendment Agreement, the Credit
           Agreement, the Note and the other Loan Documents.

           The Borrower expressly acknowledges and agrees that any failure by
the Borrower to comply with the terms and conditions of this Section 6 or any
other provisions contained in this Amendment Agreement shall constitute an Event
of Default under the Credit Agreement.

           Section 7. Expenses. The Borrower agrees to pay to the Bank upon
demand (a) an amount equal to any and all out-of-pocket costs or expenses
(including reasonable legal fees and disbursements and appraisal expenses)
incurred or sustained by the Bank in connection with the preparation of this
Amendment Agreement and related matters, including without limitation, any
reasonable legal fees in connection with any proposed amendments or financing
arrangements between the Borrower and the Bank and (b) from time to time any and
all out-of-pocket costs or expenses (including reasonable legal fees and
disbursements) hereafter incurred or sustained by the Bank in connection with
the administration of credit extended by the Bank to the Borrower or
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the preservation of or enforcement of the Bank's rights under the Credit
Agreement, the Note or the other Loan Documents or in respect of any of the
Borrower's other obligations to the Bank.

           Section 8. Release. The Borrower, on its own behalf and on behalf of
each of its successors and assigns, hereby waives, releases and discharges the
Bank and all affiliates of the Bank, and all of their directors, officers,
employees, attorneys and agents, from any and all claims, actions and causes of
action arising out of or in any way relating to the Loan Documents and any
documents, agreements, dealings or other matters connected with the Loan
Documents, including, without limitation, all known and unknown matters, claims,
transactions or things occurring on or before the date of this Amendment
Agreement related to the Loan Documents and the administration and enforcement
thereof.

           Section 9.       Miscellaneous.

                     (a) This Amendment Agreement shall be governed by and
           construed in accordance with the laws of the Commonwealth of
           Massachusetts.

                     (b) Except as otherwise expressly provided by this
           Amendment Agreement, all of the respective terms, conditions and
           provisions of the Credit Agreement shall remain the same. It is
           declared and agreed by each of the parties hereto that the Credit
           Agreement, as amended hereby, shall continue in full force and
           effect, and that this Amendment Agreement and the Credit Agreement be
           read and construed as one instrument, and all references in the Loan
           Documents to the Credit Agreement shall hereafter refer to the Credit
           Agreement, as amended by this Amendment Agreement

           IN WITNESS WHEREOF, each of the parties hereto have caused this
Agreement to be executed in its name and behalf by its duly authorized officer
as an instrument under seal as of the date first written above.

                                         FLEET NATIONAL BANK


                                         By: /s/ Suzanne Mackay
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                                             Its: Vice President

                                         DSL.NET, INC.


                                         By: /s/ Stephen Zamansky
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                                             Its: Vice President