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                                                                   EXHIBIT 10.28

March 15, 2004

Mr. Michael Ruffolo

[address]

Dear Mike:

      As we have discussed, I have determined that it is best for us to separate
at this time. I want to thank you for your efforts since 2001 to help me to
restructure Akamai and to help put the company on its path toward profitability
and continuing success. Despite the current differences between us, I want to
wish you personal success wherever your endeavors may lead.

      In connection with your separation from employment with Akamai
Technologies, Inc. ("Akamai" or the "Company") on April 9, 2004, you are
eligible to receive the benefits described in this Agreement (the "Agreement")
if you sign and return this Agreement to Tiffany Mosher-Taylor, Vice President
of Human Resources, by April 6, 2004 and do not rescind it within the seven-day
rescission period described below.

      1. SEPARATION OF EMPLOYMENT. You acknowledge that your employment with
Akamai will terminate effective April 9, 2004 (the "Separation Date"). From and
after the Separation Date, you shall have no authority, and shall not represent
yourself, as an employee or agent of Akamai.

      2. DESCRIPTION OF ADDITIONAL BENEFITS. In consideration for the
undertakings, transactions, and considerations recited in this Agreement, within
10 days after this Agreement becomes binding upon you ("Payment Date"), Akamai
agrees to provide you with the following:

      (i) A lump sum payment of Four Hundred Thousand Dollars and Zero Cents
      ($400,000.00) less all applicable federal, state, local and other
      employment-related taxes, deductions, and withholdings, in accordance with
      the Company's normal payroll practices, which sum represents one year of
      base pay (the "Severance Pay").

      (ii) Pursuant to the Restricted Stock Agreement Under Second Amended and
      Restated 1998 Stock Incentive Plan entered into on November 14, 2002, the
      Company agrees to authorize the accelerated vesting of your 175,000 shares
      of restricted stock as of April 9, 2004; and

      (iii) A lump sum cash payment of Seven Thousand Seventy-Seven Dollars and
      Zero Cents ($7,077.00), less all applicable federal, state, local and
      other employment-related taxes, deductions, and withholdings, in
      accordance with the Company's normal payroll practices, which sum
      represents an amount equal to one year's worth of the Company's current
      contribution to your medical and dental plan. You may use this money to
      cover the costs of medical and dental coverage under Consolidated Omnibus
      Budget Reconciliation Act of 1985 ("COBRA"). This payment shall be in lieu
      of reimbursement by the Company of part or all of the costs to continue
      your medical and dental coverage pursuant to COBRA. Upon timely completion
      of the forms required by COBRA, you may continue, at your sole expense,
      your medical and dental insurance coverage after the Separation Date to
      the extent permitted by COBRA. The COBRA "qualifying event" shall be
      deemed to be the Separation Date.
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Separation Letter for Mike Ruffolo
March 15, 2004
Page 2


      (iv) The Company agrees that it will instruct the Chairman and CEO,
      Members of the Office of the CEO, the Board of Directors, and the Vice
      President of Human Resources to describe your separation in accordance
      with a mutually agreed statement.

      You acknowledge and agree that the benefits described in this Section 2
are not intended to, and shall not constitute, a severance plan, and shall
confer no benefit on anyone other than the parties hereto. You further
acknowledge that except for (i) the specific financial consideration set forth
in this Agreement, (ii) wages owed for work performed up to the Separation Date,
(iii) payment of accrued and unused vacation time, (iv) expense reimbursement
for previously submitted expenses in accordance with Akamai's expense
reimbursement policies, and (v) a refund, if one is due, of your current
participation in the Employee Stock Purchase Plan ("ESPP") (if you are currently
enrolled in the ESPP, your participation in the plan will end on your
termination date) you are not, and shall not in the future be, entitled to any
other compensation including, without limitation, other wages, commissions,
bonuses, vacation pay, holiday pay, or any other form of compensation or
benefit.

      3. STOCK OPTIONS. You agree that, effective as of the close of business on
April 9, 2004, you will forfeit, and the Company will cancel, the incentive
stock option to purchase 323,438 shares of the Company's Common Stock, with a
strike price of $3.71 per share, that you were granted on May 15, 2001 and as
evidenced by an Incentive Stock Option Agreement Granted Under 1998 Stock
Incentive Plan. The Company and you agree that this paragraph shall have no
affect on your remaining option to purchase 251,562 shares of Common Stock of
the Company in which you have vested. Pursuant to the Company's 1998 Stock
Incentive Plan, you will have up to three months after the Separation Date to
exercise your stock rights. Except as described in Section 2(ii) above, all
unvested stock rights will be cancelled on the Separation Date.

      4. RETURN OF COMPANY PROPERTY. You confirm that, as of the Separation
Date, you will have returned to Akamai all Akamai records and documents (and any
copies thereof), all keys, files, equipment belonging to the Company (including,
but not limited to, computer hardware, software and printers, wireless handheld
devices, pagers, etc.), Company identification, and any other Company-owned
property in your possession or control and have left intact all electronic
Company documents, including but not limited to those which you developed or
helped to develop during your employment. You further confirm that you will have
cancelled all accounts for your benefit, if any, in the Company's name,
including but not limited to, credit cards, telephone charge cards, cellular
phone and/or pager accounts and computer accounts. Moreover, you agree that you
will not, without Akamai's express authorization, access, attempt to access or
otherwise interfere with Akamai's electronic information systems, including but
not limited to Akamai's computer, voice mail, or e-mail systems.

      5. BUSINESS EXPENSES AND COMPENSATION. You acknowledge that the Company
has reimbursed you for all costs and business expenses incurred in conjunction
with the performance of your employment and that no other reimbursements are
owed to you. You further acknowledge that you have received payment in full for
all services rendered in conjunction with your employment by the Company and
that no other compensation is owed to you.

      6. MUTUAL NON-DISPARAGEMENT. To the extent permitted by law, you
understand and agree that, as a condition for payment to you of the
consideration herein described, you shall not make any false, disparaging or
derogatory statements to anyone, including but not limited to any media outlet,
industry group, financial institution, current or former employee, consultant,
client or customer of the Company, regarding the Company or any of its
directors, officers, employees, agents or representatives or about the Company's
business affairs and financial condition, any statements that disparage any
person, product, service, finances, financial condition, capability or any other
aspect of the business of Akamai, and you will not engage in any conduct which
is intended to harm professionally or personally the
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Separation Letter for Mike Ruffolo
March 15, 2004
Page 3


reputation of Akamai (including its officers, directors, and employees). The
Company agrees to instruct its the Chairman and CEO, Members of the Office of
the CEO, the Board of Directors, and the Vice President of Human Resources with
knowledge of this Agreement not to make any false, disparaging or derogatory
statements to anyone, including but not limited to any media outlet, industry
group, or current or future employee about you or your employment with, and
separation from, the Company.

      7. MUTUAL RELEASE OF CLAIMS. In consideration of the benefits set forth in
Section 2 above and the Company's release below, which you acknowledge you would
not otherwise be entitled to receive, you hereby fully, forever, irrevocably and
unconditionally release, remise and discharge the Company, its officers,
directors, stockholders, corporate affiliates, subsidiaries, parent companies,
agents and employees (each in their individual and corporate capacities)
(hereinafter, the "Released Parties") from any and all claims, charges,
complaints, demands, actions, causes of action, suits, rights, debts, sums of
money, costs, accounts, reckonings, covenants, contracts, agreements, promises,
doings, omissions, damages, executions, obligations, liabilities, and expenses
(including attorneys' fees and costs), of every kind and nature which you ever
had or now have against the Released Parties arising out of your employment with
and/or separation from the Company, including, but not limited to, all
employment discrimination claims or employment law claims under Civil Rights
Acts of 1866 and 1871, Civil Rights Act of 1991, the Equal Pay Act, Older
Workers Benefits Protection Act, Fair Labor Standards Act, National Labor
Relations Act, Consolidated Omnibus Reconciliation Act of 1985 ("COBRA"), Title
VII of the Civil Rights Act of 1964, 42 U.S.C. Section 2000e et seq., the Age
Discrimination in Employment Act, 29 U.S.C. Section 621 et seq., --- the
Americans With Disabilities Act of 1990, 42 U.S.C., Section 12101 et seq., the
Family and Medical Leave Act, 29 U.S.C. Section 2601 et seq., and the Worker
Adjustment and Retraining Notification Act ("WARN"), 29 U.S.C. Section 2101 et
seq. all as amended; all claims arising out of the Fair Credit Reporting ---
Act, 15 U.S.C. Section 1681 et seq., the Employee Retirement Income Security Act
of 1974 ("ERISA"), 29 U.S.C. Section 1001 et seq., the Massachusetts Fair
Employment Practices Act., M.G.L. c.151B, Section 1 et seq., the Massachusetts
Civil Rights Act, M.G.L. c.12 Sections 11H and 11I, the Massachusetts Equal
Rights Act, M.G.L. c.93, Section 102 and M.G.L. c.214, Section 1C, the
Massachusetts Labor and Industries Act, M.G.L. c.149, Section 1 et seq., the
Massachusetts Privacy Act, M.G.L. c. 214, Section 1B, and the Massachusetts
Maternity Leave Act , M.G.L. c. 149, Section 105(d), all as amended; all common
law claims including, but not limited to, actions in tort, defamation and breach
of contract; all claims to any non-vested ownership interest in the Company,
contractual or otherwise, including but not limited to claims to stock or stock
options; and any claim or damage arising out of your employment with or
separation from the Company (including a claim for retaliation) under any common
law theory or any federal, state or local statute or ordinance not expressly
referenced above; provided, however, that nothing in this Agreement prevents you
from filing, cooperating with, or participating in any proceeding before the
EEOC or a state Fair Employment Practices Agency (except that you acknowledge
that you may not be able to recover any monetary benefits in connection with any
such claim, charge or proceeding).

      In consideration of the undertakings, transactions and consideration
recited in this Agreement, the Company hereby unconditionally and irrevocably
remises, releases and forever discharges you, your heirs and administrators, or
any of them, of and from any and all suits, claims, demands, interest, costs
(including attorney fees and costs actually incurred), expenses, actions and
causes of action, rights, liabilities, obligations, promises, agreements,
controversies, losses and debts, of any nature whatsoever, which the Company now
has, or at any time heretofore ever had, or could have had, whether known or
unknown, suspected or unsuspected, arising out of your employment with the
Company.

      8. FUTURE COOPERATION/INDEMNIFICATION. You agree that you shall cooperate
fully with Akamai in connection with any matter or event relating to your
employment or events that occurred during your employment, including, without
limitation, in the defense or prosecution of any claims or actions not in
existence or which may be brought or threatened in the future against or on
behalf of Akamai, including any claims or actions against its officers,
directors and employees. Your cooperation
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Separation Letter for Mike Ruffolo
March 15, 2004
Page 4


in connection with such matters, actions and claims shall include, without
limitation, being available, upon reasonable notice, to meet with Akamai
regarding matters in which you have been involved, and any contract matters or
audits; to prepare for any proceeding (including, without limitation,
depositions, consultation, discovery or trial); to provide affidavits; to assist
with any audit, inspection, proceeding or other inquiry; and to act as a witness
in connection with any litigation or other legal proceeding affecting Akamai.
You shall be reimbursed for actual and reasonable out-of-pocket expenses
incurred in providing such cooperation under this Section. To the extent
permitted by law, you further agree that should you be contacted (directly or
indirectly) by any person or entity (for example, by any party representing an
individual or entity) adverse to Akamai, you shall promptly notify Akamai's
General Counsel.

      9. NON-DISCLOSURE AND NON-COMPETITION AND NON-SOLICITATION. You
acknowledge and reaffirm your obligation to keep confidential all non-public
information concerning the Company which you acquired during the course of your
employment with the Company which remains in full force and effect, as stated
more fully in the Non-Competition and Non-Solicitation Agreement and the
Invention and Non-Disclosure Agreement ("NDAs") you signed when you began your
employment at Akamai. You further acknowledge and reaffirm that those
agreements, and your obligations there under, also remain in full force and
effect.

      10. BREACH. A breach of any provision of Section 3-9 shall constitute a
material breach of this Agreement and, in addition to any other legal or
equitable remedy available to Akamai, shall entitle Akamai to recover any monies
paid to you under Section 2, as well as to cease complying with Sections 2 (iv)
and 6, of this Agreement. You also acknowledge that the provisions of this
Section 10 are reasonable and necessary to protect Akamai's business interests,
and further that your breach of any of the covenants set forth in Sections 3-9
would constitute a material breach of the Agreement, that Akamai would suffer
substantial irreparable harm and that Akamai would not have an adequate remedy
at law for such breach. Therefore, in recognition of these acknowledgements, you
agree that in the event of a breach of any of these covenants, in addition to
such other remedies as Akamai may have at law, Akamai, without posting any bond,
shall be entitled to obtain, and you agree not to oppose, a request for
equitable relief in the form of specific performance or temporary, preliminary
or permanent injunctive relief, or any other equitable remedy which then may be
available. The seeking of such injunction or order shall not affect Akamai's
right to seek and obtain damages or other equitable relief on account of any
such actual. You further acknowledge and agree to enforcement of these covenants
under the laws of and in the Commonwealth of Massachusetts, where Akamai
maintains its worldwide headquarters, where all personnel and benefit plans are
administered, documents maintained, where this Agreement has been executed by
Akamai, and where witnesses and documents relating to any dispute would be
primarily located.

      11. AMENDMENT. This Agreement shall be binding upon the parties and may
not be modified in any manner, except by an instrument in writing of concurrent
or subsequent date signed by duly authorized representatives of the parties
hereto. This Agreement is binding upon and shall inure to the benefit of the
parties and their respective agents, assigns, heirs, executors, successors and
administrators.

      12. WAIVER OF RIGHTS. No delay or omission by the Company in exercising
any right under this Agreement shall operate as a waiver of that or any other
right. A waiver or consent given by the Company on any one occasion shall be
effective only in that instance and shall not be construed as a bar or waiver of
any right on any other occasion.

      13. VALIDITY. Should any provision of this Agreement be declared or be
determined by any court of competent jurisdiction to be illegal or invalid, the
validity of the remaining parts, terms or provisions shall not be affected
thereby and said illegal or invalid part, term or provision shall be deemed not
to be a part of this Agreement.
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Separation Letter for Mike Ruffolo
March 15, 2004
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      14. CONFIDENTIALITY. You understand and agree that as a condition for
payment to you and of the Company's description of your separation and
non-disparagement obligations, herein described, the terms and contents of this
Agreement, and the contents of the negotiations and discussions resulting in
this Agreement, shall be maintained as confidential by you and your agents and
representatives and shall not be disclosed except to the extent required by
federal or state law or as otherwise agreed to in writing by the Company.

      15. ACKNOWLEDGMENTS. It is Akamai's desire and intent to make certain that
you fully understand the provisions and effects of this Agreement. To that end,
you have been encouraged and given the opportunity to consult with legal counsel
before signing below and returning this Agreement to Tiffany Mosher-Taylor, Vice
President of Human Resources, Akamai Technologies, Inc., 8 Cambridge Center,
Cambridge, MA 02142. You may take up to twenty-one (21) days (until close of
business on April 6, 2004) to sign this Agreement. In addition, if you sign this
Agreement within that time period, you may change your mind and rescind your
assent to this Agreement if, within seven (7) days after you sign this
Agreement, you deliver a notice of rescission to Tiffany Mosher-Taylor, Vice
President of Human Resources, at Akamai. To be effective, such rescission must
be hand delivered or postmarked within the seven (7) day period and sent by
certified mail, return receipt requested, to Tiffany Mosher-Taylor, Vice
President of Human Resources, Akamai Technologies, Inc., 8 Cambridge Center,
Cambridge, MA 02142. If you do not so rescind, this Agreement will become a
binding agreement between you and the Company upon the expiration of the seven
(7) day rescission period

      If you choose not to sign and return this Agreement by April 6, 2004, for
the reasons previously discussed, you shall not receive any benefits from the
Company. You will, however, receive payment on your separation from employment
for any unused vacation time accrued through the separation date. Also,
regardless of signing this Agreement, you may elect to continue receiving group
medical insurance pursuant to COBRA. You shall pay all premium costs on a
monthly basis for as long as, and to the extent that, you remain eligible for
COBRA continuation. You should consult the COBRA materials to be provided by the
Company for details regarding these benefits. All other benefits, including life
insurance and long-term disability, will cease upon your Separation Date.

      You acknowledge that you have been given at least twenty-one (21) days to
consider this Agreement and that the Company advised you to consult with an
attorney of your own choosing prior to signing this Agreement. You understand
that you may revoke this Agreement for a period of seven (7) days after you sign
this Agreement, and this Agreement shall not be effective or enforceable until
the expiration of this seven (7) day revocation period. YOU UNDERSTAND AND AGREE
THAT BY ENTERING INTO THIS AGREEMENT YOU ARE WAIVING ANY AND ALL RIGHTS OR
CLAIMS YOU MIGHT HAVE UNDER THE AGE DISCRIMINATION IN EMPLOYMENT ACT, AS AMENDED
BY THE OLDER WORKERS BENEFIT PROTECTION ACT, AND THAT YOU HAVE RECEIVED
CONSIDERATION BEYOND THAT TO WHICH YOU WERE PREVIOUSLY ENTITLED.

      16. VOLUNTARY ASSENT. You affirm that no other promises or agreements of
any kind have been made to or with you by any person or entity whatsoever to
cause you to sign this Agreement, and that you fully understand the meaning and
intent of this Agreement. You state and represent that you have had an
opportunity to fully discuss and review the terms of this Agreement with an
attorney. You further state and represent that you have carefully read this
Agreement, understand the contents herein, freely and voluntarily assent to all
of the terms and conditions hereof, and sign your name of your own free act.

      17. APPLICABLE LAW. This Agreement shall be interpreted and construed by
the laws of the Commonwealth of Massachusetts, without regard to conflict of
laws provisions. You hereby irrevocably submit to and acknowledge and recognize
the jurisdiction of the courts of the Commonwealth of
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Separation Letter for Mike Ruffolo
March 15, 2004
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Massachusetts, or if appropriate, a federal court located in Massachusetts
(which courts, for purposes of this Agreement, are the only courts of competent
jurisdiction), over any suit, action or other proceeding arising out of, under
or in connection with this Agreement or the subject matter hereof. You also
acknowledge that venue for such actions shall lie exclusively in Massachusetts
and that material witnesses and documents are located in Massachusetts.

      18. ENTIRE AGREEMENT. Except for the NDAs, this Agreement contains and
constitutes the entire understanding and agreement between the parties hereto
with respect to your additional benefits and the settlement of claims against
the Company and cancels all previous oral and written negotiations, agreements,
commitments, writings in connection therewith. Nothing in this paragraph,
however, shall modify, cancel or supersede your obligations set forth in this
Agreement. The provisions of this Agreement are severable and if, for any
reason, any part hereof shall be found to be unenforceable, the remaining
provisions shall be enforced in full.

            If you have any questions about the matters covered in this
Agreement, please call Tiffany Mosher-Taylor.

                                    Very truly yours,



                                    AKAMAI TECHNOLOGIES, INC.

                                    By:   /s/ George H. Conrades
                                          -----------------------
                                          George H. Conrades
                                          Chairman and CEO


            I hereby agree to the terms and conditions set forth above. I have
been given at least twenty-one (21) days to consider this Agreement and I have
chosen to execute this on the date below. I intend that this Agreement become a
binding agreement between the Company and me if I do not revoke my acceptance in
seven (7) days.

/s/ Michael Ruffolo                             Date March 22, 2004
------------------------------                       --------------
MICHAEL RUFFOLO


To be returned by April 6, 2004