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                                                                    EXHIBIT 10.2

                 SECURITY AGREEMENT AND ASSIGNMENT OF ACCOUNT
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                                                          Date: December 3, 1999

TO:  BANKBOSTON, N.A. (the "Bank"), a national banking association having its
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Head Office at 100 Federal Street, Boston, Massachusetts 02110:

        1.  ASSIGNMENT OF ACCOUNT. FOR VALUE RECEIVED, and in consideration of
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the Bank giving, in its discretion, time, credit or banking facilities or
accommodations to NaviSite Inc. (the "Company") and certain of the Company's
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subsidiaries (collectively, the "Borrowers" and each individually, a
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"Borrower"), the undersigned (jointly and severally if more than one) hereby
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pledges, assigns and transfers all of its right, title and interest in and to,
and grants to the Bank a security interest in all mutual funds, cash,
instruments, securities and other investment property now or hereafter as
maintained or held in that certain Loan Collateral Account #OFFK 522 137343-CL
(collectively, "Collateral") in an aggregate amount of not less than
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$10,325,238.52 or such greater amount which constitutes all Obligations to the
Bank, together with all interest, dividends and income thereon and all sums now
or at any time hereafter on deposit therein or due thereon and any instruments,
investments, securities or other investment property purchased with the proceeds
thereof, and any and all proceeds and products of any of the foregoing
(collectively, the "Account"), as collateral security for the payment and
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performance of the following (collectively, the "Obligations"): any and all
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obligations of the Borrowers and the undersigned to the Bank or any of its
branches and affiliates of every kind and description, whether direct or
indirect, absolute or contingent, primary or secondary, joint or several, due or
to become due, now existing or hereafter arising or acquired including, without
limitation, all obligations of the Company to the Bank arising from a standby
letter of credit number 501 03433 in an aggregate amount of not less than
$10,325,238.52 or such greater amount which represents the actual obligation
(together with all agreements and instruments executed in connection with any of
the foregoing, and as the same may from time to time be modified, amended,
extended or replaced, the "Loan Documents"). The Bank hereby agrees that if at
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any time, any of the Obligations have matured and are indefeasibly repaid in
full, the Bank shall immediately reduce the amount required to be held in the
Account by the amount of such repayment. In addition, the Bank hereby agrees
that if at any time, any of the obligations are permanently reduced (but not
reduced to zero), the Bank shall reduce the amount required to be held by the
Bank in the Account by the amount of such permanent reduction.

        2.  REPRESENTATIONS, WARRANTIES AND COVENANTS.
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        2.1 The undersigned represents and warrants that (a) the undersigned has
the right and legal authority to execute and deliver this Assignment; (b) except
for any financing statement which may have been filed by the Bank, no financing
statement covering the Account has been filed with any filing office; (c) no
other assignment or security agreement has been executed with respect to the
Account; (d) the Account is not subject to any liens, offsets or rights of any
person or entity other than the Bank; (e) if the undersigned is a corporation,
the opening of the Account, the deposit of funds therein and the assignment and
pledge thereof pursuant to the terms of this Assignment have been authorized by
all necessary corporate action and do not contravene any provision of its
constituent documents or any law, regulation, decree, order or agreement binding
on the undersigned; and (f) this Assignment represents the legal, valid and
binding obligation of the undersigned, enforceable in accordance with its terms.

        2.2 So long as any of the Obligations remain outstanding, the
undersigned: (a) will execute and deliver to the Bank all such other documents,
and take such other actions, as and when the Bank may from time to time request
in order to more fully evidence and perfect the Bank's interest in the Account;
(b) will not take or permit to be taken any action of any kind with respect to
the Account, including any attempt to transfer, assign or create in favor of any
party other than the Bank a security interest in, the Account; (c) will not
make, or allow to be made, any withdrawals from the Account and will not close
the Account; and (d) will immediately segregate from all other funds of the
undersigned and hold in trust for the Bank any funds received from the Account
in violation of this Assignment, and will not exercise dominion or control over
such funds except to pay them immediately into the Account.

        3.  DEFAULT; REMEDIES. Upon the occurrence of any default in the payment
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or performance of any obligation under this Assignment or any other Obligation
(after giving effect to any grace periods

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applicable thereto) and so long as such default shall be continuing, the Bank
may declare the Obligations immediately due and payable and may (i) withdraw
immediately all or any portion of the funds on deposit in or payable on the
Account, and apply such funds to the payment of the Obligations in such order
and manner as the Bank, in its sole discretion, may elect; (ii) on behalf of the
undersigned endorse the name of the undersigned upon any checks, drafts, or
other instruments payable to the undesigned evidencing payment on the Account;
(iii) surrender or present for withdrawal the passbook, certificate or other
documents issued to the undersigned in connection with the Account; (iv)
liquidate any Collateral on such terms as the Bank may determine whether by
private or public sale and notify any third party, including the Securities
Intermediary, to liquidate the Collateral on behalf of the Bank and direct the
proceeds thereof to the Bank for application to payment of the Obligations in
such order as the Bank may determine. All transaction costs relating to exercise
of any of the Bank's rights or remedies hereunder shall be borne by the
undersigned and the Bank may deduct any such costs from proceeds of the
Collateral before application of such proceeds to the Obligations. Any such
third party may rely on this Assignment as conclusive evidence that the Bank has
the power and authority to provide any notice or direction relating to the
Collateral as the Bank deems necessary in order to exercise any rights and
remedies available to the Bank relating to the Collateral.

     4.  BANK AS ATTORNEY-IN-FACT.  The undersigned appoints the Bank as its
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attorney-in-fact for the purposes of carrying out the provisions of this
Assignment and taking any action and executing any instrument that the Bank may
deem necessary or advisable to accomplish the purposes hereof. This power of
attorney shall be irrevocable and shall not terminate upon the death or any
disability of the undersigned.

     5.  RIGHTS OF BANK; INDEMNIFICATION.
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     5.1 The Bank shall not be liable for its failure to use due diligence in
the collection of the Obligations, or for any action or omission in connection
therewith, or for any loss of interest on, or penalty assessed against, funds in
or payable on the Account as a result of the Bank's exercising any of its rights
or remedies under this Assignment. The Bank may exercise its rights with respect
to the Account and the Collateral without resorting, or regard, to other
collateral or sources of reimbursement for the Obligations. No delay or omission
on the part of the Bank in exercising any right shall operate as a waiver of
such right or any other right. A waiver on any one occasion shall not bar or
waive the exercise of any right on any future occasion. All rights and remedies
of the Bank, whether evidenced hereby or by any other agreement, are cumulative
and not exclusive of any remedies provided by law or any other agreement, and
may be exercised separately or concurrently.

     5.2 The undersigned shall indemnify and hold harmless the Bank from and
against any liability or damage which the Bank may incur in the exercise and
performance, in good faith, of any of the Bank's powers and duties set forth
herein.

     6.  WAIVERS BY THE UNDERSIGNED.  The undersigned waives presentment,
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demand, notice, protest, notice of acceptance of this Assignment, notice of any
loans made, credit or other extensions granted, collateral received or delivered
or any other action taken in reliance hereon and all other demands and notices
of any description, except for such demands and notices as are expressly
required to be provided to the undersigned under this Assignment or any other
document evidencing the Obligations. With respect to both the Obligations and
the Account, the undersigned assents to any extension or postponement of the
time of payment or any other forgiveness or indulgence, to any substitution,
exchange or release of any collateral securing the Obligations, to the addition
or release of any party or person primarily or secondarily liable, to the
acceptance of partial payment thereon and the settlement, compromise or
adjustment of any thereof, all in such manner and at such time or times as the
Bank may deem advisable. The undersigned waives all rights against the Borrower
arising hereunder by way of subrogation, reimbursement, indemnification,
contribution or otherwise; the undersigned will not prove any claim in
competition with the Bank in respect of any payment hereunder in bankruptcy or
insolvency proceedings of any nature; and the undersigned will not claim any
set-off or counterclaim against the Borrower in respect of any liability of the
undersigned to the Borrower.

     7.  NOTICES.  Any demand upon or notice to the undersigned that the Bank
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may give shall be effective when delivered by hand, properly deposited in the
mails postage prepaid, or sent by telex, answerback received, or electronic
facsimile transmission, receipt acknowledged, or delivered to a telegraph
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company or overnight courier, in each case addressed to the undersigned at the
address shown next to its signature at the end of this Assignment or as it
appears on the books and records of the Bank. Demands or notices addressed to
any other address at which the Bank customarily communicates with the
undersigned also shall be effective. Any notice of the undersigned to the Bank
shall be given as aforesaid, addressed to the Bank at the address shown at the
beginning of this Assignment or such other address as the Bank may advise the
undersigned in writing.

        8. TERMINATION; REINSTATEMENT. This Assignment shall remain in full
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force and effect until the Obligations have been repaid in full and the Bank
shall have no further obligation to extend credit to the Borrower or the
undersigned.

        9. SUCCESSORS AND ASSIGNS. This Assignment shall be binding upon the
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undersigned, its successors and assigns, and shall inure to the benefit of and
be enforceable by the Bank and its successors and assigns. Without limiting the
generality of the foregoing sentence, the Bank may transfer any agreement or any
note held by it evidencing, securing or otherwise executed in connection with
the Obligations, or sell participations in any interest therein, to any other
person or entity, and such other person or entity shall thereupon become vested,
to the extent set forth in the agreement evidencing such assignment, transfer or
participation, with all the rights in respect thereof granted to the Bank
herein.

        10. GENERAL. The provisions of this Assignment may not be amended,
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modified or waived except by a writing signed by the undersigned and the Bank,
nor may the undersigned assign any of its rights hereunder. This Assignment and
the terms, covenants and conditions hereof shall be construed in accordance
with, and governed by, the laws of The Commonwealth of Massachusetts (without
giving effect to any conflicts of law provisions contained therein). In the
event that the Account is held or stands in the name of the undersigned and
another or others jointly, the Bank may deal with the same for all purposes as
if it belonged to or stood in the name of the undersigned alone. Section
headings are for convenience of reference only and are not a part of this
Assignment.

        11. JURY WAIVER. THE BANK (BY ITS ACCEPTANCE OF THIS ASSIGNMENT) AND THE
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UNDERSIGNED AGREE THAT NEITHER OF THEM NOR ANY ASSIGNEE OR SUCCESSOR SHALL (A)
SEEK A JURY TRIAL IN ANY LAWSUIT, PROCEEDING, COUNTERCLAIM, OR ANY OTHER ACTION
BASED UPON, OR ARISING OUT OF, THIS ASSIGNMENT, ANY RELATED INSTRUMENTS, ANY
COLLATERAL OR THE DEALINGS OR THE RELATIONSHIP BETWEEN OR AMONG ANY OF THEM, OR
(B) SEEK TO CONSOLIDATE ANY SUCH ACTION WITH ANY OTHER ACTION IN WHICH A JURY
TRIAL CANNOT BE OR HAS NOT BEEN WAIVED. THE PROVISIONS OF THIS PARAGRAPH SHALL
BE SUBJECT TO NO EXCEPTIONS. NEITHER THE BANK NOR THE UNDERSIGNED HAS AGREED
WITH OR REPRESENTED TO THE OTHER THAT THE PROVISIONS OF THIS PARAGRAPH WILL NOT
BE FULLY ENFORCED IN ALL INSTANCES.

        IN WITNESS WHEREOF, the undersigned has caused this Assignment to be
duly executed as an instrument under seal as of the date first written above.


                                        NaviSite Inc.


                                        /s/ Kenneth W. Hale
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                                        By:
                                        Title: