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                                                                     EXHIBIT 4.1
================================================================================


                                                             CUSIP: 25389F AB 0

                                                              ISIN: US25389FAB04


No. __                                                               $__________



                                DIGITALNET, INC.



                            9% Senior Notes due 2010


Issue Date:  _______, 2003


                  DigitalNet, Inc., a Delaware corporation (the "ISSUER", which
term includes any successor under the Indenture hereinafter referred to), for
value received, promises to pay to CEDE & CO., or its registered assigns, the
principal sum of ________________________________ ($___________), as such sum
may be listed on the Schedule of Exchanges of Interests in the Global Note
attached hereto on July 3, 2010.


Interest Payment Dates:  January 15 and July 15, commencing January 15, 2004.


Record Dates:  January 1 and July 1.


                  Reference is hereby made to the further provisions of this
Note set forth on the reverse hereof, which further provisions shall for all
purposes have the same effect as if set forth at this place.



================================================================================

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          IN WITNESS WHEREOF, the Issuer has caused this Note to be signed
manually or by facsimile by its duly authorized officers.



<Table>
<S>                                                  <C>
                                                     DIGITALNET, INC.

                                                       by
                                                          ------------------------------------------
                                                          Name:  Ken S. Bajaj
                                                          Title: President, Chief Executive
                                                                 Officer and Chairman of the
                                                                 Board of Directors

                                                       by
                                                          ------------------------------------------
                                                          Name:  Jack Pearlstein
                                                          Title: Secretary, Treasurer and Chief
                                                                 Financial Officer
</Table>



                    (Trustee's Certificate of Authentication)


This is one of the 9% Senior Notes due 2010 described in the within-mentioned
Indenture.

Dated:  _______, 2003

WELLS FARGO BANK MINNESOTA,
NATIONAL ASSOCIATION,

as Trustee

     by

          -----------------------------------------------
          Name:  Joseph P. O'Donnell
          Title: Corporate Trust Officer

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                           For value received, each Guarantor (which term
         includes any successor Person under the Indenture) has, jointly and
         severally, unconditionally guaranteed, to the extent set forth in the
         Indenture and subject to the provisions in the Indenture dated as of
         July 3, 2003 (the "Indenture") among DigitalNet, Inc., the other
         Guarantors (as defined in the Indenture) and Wells Fargo Bank
         Minnesota, National Association, as trustee (the "Trustee"), (a) the
         due and punctual payment of the principal of, premium, if any, and
         interest and Liquidated Damages, if any, on the Notes (as defined in
         the Indenture), whether at maturity, by acceleration, redemption or
         otherwise, and the due and punctual payment of interest on overdue
         principal, premium, if any, and interest and Liquidated Damages, if
         any, on the Notes, if lawful (subject in all cases to any applicable
         grace period provided in the Indenture), and the due and punctual
         performance of all other obligations of the Issuer to the Holders or
         the Trustee all in accordance with the terms of the Indenture and the
         Notes and (b) in case of any extension of time of payment or renewal of
         any Notes or any of such other obligations, the same will be promptly
         paid in full when due or performed in accordance with the terms of the
         extension or renewal, whether at stated maturity, by acceleration or
         otherwise. The obligations of the Guarantors to the Holders of Notes
         and to the Trustee pursuant to the Note Guarantee and the Indenture are
         expressly set forth in Article Ten of the Indenture and reference is
         hereby made to the Indenture for the precise terms of the Note
         Guarantee. Each Holder of a Note, by accepting the same, (a) agrees to
         and shall be bound by such provisions and (b) appoints the Trustee
         attorney-in-fact of such Holder for such purpose.


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                  IN WITNESS HEREOF, each Guarantor has caused this Notation of
Guarantee to be signed manually or by facsimile by its duly authorized officer.


<Table>
<S>                                    <C>
                                       DIGITALNET HOLDINGS, INC.

                                         by
                                           ---------------------------------------
                                           Name:  Ken S. Bajaj
                                           Title: President, Chief Executive
                                                  Officer and Chairman of the
                                                  Board of Directors

                                         by
                                           ---------------------------------------
                                           Name:  Jack Pearlstein
                                           Title: Secretary, Treasurer and Chief
                                                  Financial Officer

                                       DIGITALNET GOVERNMENT SOLUTIONS, LLC

                                         by
                                           ---------------------------------------
                                           Name:  Ken S. Bajaj
                                           Title: Chief Executive Officer and
                                                  Chairman of the Board of Managers

                                         by
                                           ---------------------------------------
                                           Name:  Jack Pearlstein
                                           Title: Senior Vice President and
                                                  Assistant Secretary
</Table>

<Page>

                                DIGITALNET, Inc.

                            9% Senior Notes due 2010


THIS GLOBAL NOTE IS HELD BY THE DEPOSITARY (AS DEFINED IN THE INDENTURE
GOVERNING THIS NOTE) OR ITS NOMINEE IN CUSTODY FOR THE BENEFIT OF THE BENEFICIAL
OWNERS HEREOF, AND IS NOT TRANSFERABLE TO ANY PERSON UNDER ANY CIRCUMSTANCES
EXCEPT THAT (I) THE TRUSTEE MAY MAKE SUCH NOTATIONS HEREON AS MAY BE REQUIRED
PURSUANT TO SECTION 2.07 OF THE INDENTURE, (II) THIS GLOBAL NOTE MAY BE
EXCHANGED IN WHOLE BUT NOT IN PART PURSUANT TO SECTION 2.07(a) OF THE INDENTURE,
(III) THIS GLOBAL NOTE MAY BE DELIVERED TO THE TRUSTEE FOR CANCELLATION PURSUANT
TO SECTION 2.12 OF THE INDENTURE AND (IV) THIS GLOBAL NOTE MAY BE TRANSFERRED TO
A SUCCESSOR DEPOSITARY WITH THE PRIOR WRITTEN CONSENT OF THE ISSUER.


                  Capitalized terms used herein shall have the meanings assigned
to them in the Indenture referred to below unless otherwise indicated.

              (1) INTEREST. The Issuer promises to pay interest on the principal
     amount of this Note at 9% per annum from the date hereof until maturity
     and shall pay the Liquidated Damages, if any, payable pursuant to
     Section 5 of the Registration Rights Agreement referred to below. The
     Issuer shall pay interest and Liquidated Damages, if any, semi-annually
     in arrears on January 15 and July 15 of each year, or if any such day is
     not a Business Day, on the next succeeding Business Day (each an
     "INTEREST PAYMENT DATE"). Interest on the Notes shall accrue from the
     most recent date to which interest has been paid or, if no interest has
     been paid, from the date of original issuance; PROVIDED that if there is
     no existing Default in the payment of interest, and if this Note is
     authenticated between a record date referred to on the face hereof and
     the next succeeding Interest Payment Date, interest shall accrue from
     such next succeeding Interest Payment Date; PROVIDED FURTHER that the
     first Interest Payment Date shall be January 15, 2004. The Issuer shall
     pay interest (including post-petition interest in any proceeding under
     any Bankruptcy Law) on overdue principal and premium, if any, from time
     to time on demand at a rate that is 1% per annum in excess of the rate
     then in effect; it shall pay interest (including post-petition interest
     in any proceeding under any Bankruptcy Law) on overdue installments of
     interest and Liquidated Damages (without regard to any applicable grace
     periods) from time to time on demand at the same rate to the extent
     lawful. Interest shall be computed on the basis of a 360-day year of
     twelve 30-day months.

              (2) METHOD OF PAYMENT. The Issuer shall pay interest on the Notes
     (except defaulted interest) and Liquidated Damages, if any, to the
     Persons who are registered Holders of Notes at the close of business on
     the record date immediately preceding the Interest Payment Date, even if
     such Notes are canceled after such record date and on or before such
     Interest Payment Date, except as provided in Section 2.13 of the
     Indenture with

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     respect to defaulted interest. The Notes shall be payable as to principal,
     premium and Liquidated Damages, if any, and interest at the office or
     agency of the Issuer maintained for such purpose in The City of New York,
     or, at the option of the Issuer, payment of interest and Liquidated
     Damages, if any, may be made by check mailed to the Holders at their
     addresses set forth in the register of Holders, and provided that payment
     by wire transfer of immediately available funds shall be required with
     respect to principal of and interest, premium and Liquidated Damages, if
     any, on, all Global Notes and to any Holder which shall have provided wire
     transfer instructions to the Issuer or the Paying Agent as provided in
     Section 2.03 of the Indenture. Such payment shall be in such coin or
     currency of the United States of America as at the time of payment is legal
     tender for payment of public and private debts.

              (3) PAYING AGENT AND REGISTRAR. Initially, the Trustee under the
     Indenture shall act as Paying Agent and Registrar. The Issuer may change
     any Paying Agent or Registrar without notice to any Holder. The Issuer
     or any of its Subsidiaries may act in any such capacity.

              (4) INDENTURE. The Issuer issued the Notes under an Indenture
     dated as of July 3, 2003 ("INDENTURE") among the Issuer, the Guarantors
     and the Trustee. The terms of the Notes include those stated in the
     Indenture and those made part of the Indenture by reference to the Trust
     Indenture Act of 1939, as amended. The Notes are subject to all such
     terms, and Holders are referred to the Indenture and such Act for a
     statement of such terms. To the extent any provision of this Note
     conflicts with the express provisions of the Indenture, the provisions
     of the Indenture shall govern and be controlling. The Indenture pursuant
     to which this Note is issued provides that an unlimited aggregate
     principal amount of Additional Notes may be issued thereunder.

              (5) OPTIONAL REDEMPTION.

                  (a) Except as set forth in paragraph 5(b) below, the Issuer
          shall not have the option to redeem any Notes prior to July 15,
          2007. Thereafter, the Issuer shall have the option to redeem the
          Notes, in whole or in part, upon not less than 30 nor more than 60
          days' prior notice, at the redemption prices (expressed as
          percentages of principal amount) set forth below plus accrued and
          unpaid interest and Liquidated Damages, if any, thereon to the
          applicable redemption date, if redeemed during the twelve-month
          period beginning on July 15, of the years indicated below (subject
          to the right of Holders on the relevant record date to receive
          interest due on the related interest payment date):

<Table>
<Caption>
     YEAR                                                                                PERCENTAGE
     ----                                                                                ----------
    <S>                                                                                  <C>
     2007.........................................................................       104.50%
     2008.........................................................................       102.25%
     2009 and thereafter..........................................................       100.00%
</Table>

                  (b) Notwithstanding the foregoing, at any time prior to
          July 15, 2006, the Issuer may redeem up to 35% of the aggregate
          principal amount of Notes originally issued under the Indenture
          (calculated giving effect to any issuance of Additional Notes) at a
          redemption price of 109% of the principal amount thereof, plus
          accrued and unpaid interest and Liquidated Damages, if any, to the
          redemption date, with the net cash

<Page>

          proceeds of one or more Equity Offerings of the Issuer; PROVIDED
          that (A) at least 65% of the aggregate principal amount of the
          Notes originally issued under the Indenture (calculated giving
          effect to any issuance of Additional Notes) remains outstanding
          immediately after the occurrence of such redemption, excluding
          Notes held by the Issuer and its Subsidiaries; and (B) the
          redemption must occur within 90 days of the date of the closing of
          such Equity Offering.

              (6) REPURCHASE AT OPTION OF HOLDER.

                  (a) If a Change of Control occurs, each Holder of Notes will
          have the right to require the Issuer to repurchase all or any part
          (equal to $1,000 or an integral multiple thereof) of such Holder's
          Notes pursuant to an offer by the Issuer (a "Change of Control
          Offer") at an offer price (a "Change of Control Payment") in cash
          equal to 101% of the aggregate principal amount thereof plus
          accrued and unpaid interest and Liquidated Damages, if any, thereon
          to the date of purchase; PROVIDED, HOWEVER, that notwithstanding
          the occurrence of a Change of Control, the Issuer will not be
          obligated to offer to purchase or purchase the Notes pursuant to
          Section 4.14 of the Indenture if, prior to the time that the Issuer
          would be required to offer to purchase the Notes as a result of
          such Change of Control, the Issuer has mailed the requisite
          irrevocable notice to redeem all the outstanding Notes pursuant to
          Section 3.03 of the Indenture and redeems all the Notes in
          accordance with such notice. Within 30 days following any Change of
          Control, the Issuer will mail a notice to each Holder describing
          the transaction or transactions that constitute the Change of
          Control and offering to repurchase Notes on a date (the "Change of
          Control Payment Date") specified in such notice, which shall be no
          earlier than 30 days and no later than 60 days from the date such
          notice is mailed, pursuant to the procedures required by the
          Indenture and described in such notice.

                  (b) Upon certain circumstances specified in the Indenture,
          the Issuer may be required to repurchase the Notes with the
          proceeds of any Asset Sale.

              (7) DENOMINATIONS, TRANSFER, EXCHANGE. The Notes are in registered
     form without coupons in denominations of $1,000 and integral multiples
     of $1,000. The transfer of Notes may be registered and Notes may be
     exchanged as provided in the Indenture. The Registrar and the Trustee
     may require a Holder, among other things, to furnish appropriate
     endorsements and transfer documents and the Issuer may require a Holder
     to pay any taxes and fees required by law or permitted by the Indenture.
     The Issuer is not required to transfer or exchange any Note selected for
     redemption. Also, the Issuer is not required to transfer or exchange any
     Note for a period of 15 days before a selection of Notes to be redeemed.
     Transfer may be restricted as provided in the Indenture.

              (8) PERSONS DEEMED OWNERS. The registered Holder of a Note will
     be treated as its owner for all purposes.

              (9) AMENDMENT, SUPPLEMENT AND WAIVER. Subject to certain
     exceptions, the Indenture or the Notes may be amended or supplemented
     with the consent of the Holders of at least a majority in principal
     amount of the then outstanding Notes (including, without limitation,
     consents obtained in connection with a purchase of, or tender offer or

<Page>

     exchange offer for, the Notes), and any existing default or compliance with
     any provision of the Indenture or the Notes may be waived with the consent
     of the Holders of a majority in principal amount of the then outstanding
     Notes (including, without limitation, consents obtained in connection with
     a purchase of, or tender offer or exchange offer for, the Notes). Without
     the consent of any Holder of a Note, the Indenture or the Notes may be
     amended or supplemented to, among other things, cure any ambiguity,
     omission, defect or inconsistency, or to make any change that does not
     adversely affect the legal rights under the Indenture of any such Holder.

              (10) DEFAULTS AND REMEDIES. In the case of an Event of Default
     arising from certain events of bankruptcy or insolvency, with respect to
     DigitalNet Holdings, any Subsidiary of DigitalNet Holdings that owns
     Equity Interests of the Issuer, the Issuer, any Subsidiary Guarantor or
     any Significant Subsidiary of the Issuer, all outstanding Notes will
     become due and payable immediately without further action or notice. If
     any other Event of Default occurs and is continuing, the Trustee or the
     Holders of at least 25% in principal amount of the then outstanding
     Notes may declare all the Notes to be due and payable immediately by
     notice in writing to the Issuer specifying the Event of Default. Holders
     of the Notes may not enforce the Indenture or the Notes except as
     provided in the Indenture. Subject to certain limitations, Holders of a
     majority in principal amount of the then outstanding Notes may direct
     the Trustee in its exercise of any trust or power. Holders of a majority
     in principal amount of the then outstanding Notes by notice to the
     Trustee may on behalf of the Holders of all of the Notes waive any
     existing Default or Event of Default and the consequences provided in
     the Indenture, except a continuing Default or Event of Default in the
     payment of interest or Liquidated Damages on, or the principal of, the
     Notes; PROVIDED, HOWEVER that the Holders of a majority in principal
     amount of the then outstanding Notes may rescind an acceleration
     pursuant to Section 6.02 of the Indenture, and its consequences if
     certain conditions are satisfied.

              In the case of any Event of Default occurring by reason of any
     willful action or inaction taken or not taken by or on behalf of the Issuer
     with the intention of avoiding payment of the premium that the Issuer would
     have had to pay if the Issuer then had elected to redeem the Notes pursuant
     to Section 3.07(a) of the Indenture, an equivalent premium shall also
     become and be immediately due and payable to the extent permitted by law
     upon the acceleration of the Notes. If an Event of Default occurs during
     any time that the Notes are outstanding, by reason of any willful action
     (or inaction) taken (or not taken) by or on behalf of the Issuer with the
     intention of avoiding the prohibition on redemption of the Notes, then the
     premium specified in Section 3.07(b) of the Indenture shall also become
     immediately due and payable to the extent permitted by law upon the
     acceleration of the Notes.

              (11) TRUSTEE DEALINGS WITH ISSUER. The Trustee, in its individual
     or any other capacity, may make loans to, accept deposits from, and
     perform services for the Issuer or its Affiliates, and may otherwise
     deal with the Issuer or its Affiliates, as if it were not the Trustee.

              (12) NO RECOURSE AGAINST OTHERS. No director, officer, employee,
     incorporator or stockholder of the Issuer or any Guarantor, as such,
     shall have any liability for any obligations of the Issuer or the
     Guarantors under the Notes, the Indenture, the Note

<Page>

     Guarantees or for any claim based on, in respect of, or by reason of, such
     obligations or their creation. Each Holder of Notes by accepting a Note
     waives and releases all such liability. The waiver and release are part of
     the consideration for issuance of the Notes.

              (13) AUTHENTICATION. This Note shall not be valid until
     authenticated by the manual signature of the Trustee or an authenticating
     agent.

              (14) ADDITIONAL RIGHTS OF HOLDERS OF RESTRICTED GLOBAL NOTES AND
     RESTRICTED DEFINITIVE NOTES. In addition to the rights provided to
     Holders under the Indenture, Holders of Restricted Global Notes and
     Restricted Definitive Notes shall have all the rights set forth in the
     Registration Rights Agreement dated as of July 3, 2003, between the
     Issuer, the Guarantors and the parties named on the signature pages
     thereof (the "REGISTRATION RIGHTS AGREEMENT") or, in the case of
     Additional Notes, Holders of Restricted Global Notes and Restricted
     Definitive Notes shall have the rights set forth in one or more
     registration rights agreements, if any, between the Issuer, the
     Guarantors and the other parties thereto, relating to rights given by
     the Issuer and the Guarantors to the purchasers of Additional Notes.

              (15) CUSIP AND ISIN NUMBERS. The Issuer has caused CUSIP and
     ISIN numbers to be printed on the Notes and the Trustee may use CUSIP
     and ISIN numbers in notices of redemption as a convenience to Holders.
     No representation is made as to the accuracy of such numbers either as
     printed on the Notes or as contained in any notice of redemption and
     reliance may be placed only on the other identification numbers placed
     thereon.

              (16) GUARANTEE. The Issuer's obligations under the Notes are
     fully and unconditionally guaranteed, jointly and severally, by the
     Guarantors.

              (17) ABBREVIATIONS. Customary abbreviations may be used in the
     name of a Holder or an assignee, such as TEN COM (=tenants in common),
     TEN ENT (=tenants by the entireties), JT TEN (=joint tenants with rights
     of survivorship and not as tenants in common), CUST (=custodian), and
     U/G/M/A (=Uniform Gift to Minors Act).

              (18) COPIES OF DOCUMENTS. The Issuer shall furnish to any Holder
     upon written request and without charge a copy of the Indenture and/or the
     Registration Rights Agreement. Requests may be made to:

                           DigitalNet Holdings, Inc.
                           2525 Network Place
                           Herndon, Virginia

                           Facsimile: 703-563-7616
                           Attention: Jack Pearlstein

              (19) GOVERNING LAW. THE LAWS OF THE STATE OF NEW YORK SHALL
     GOVERN AND BE USED TO CONSTRUE THE INDENTURE, THE NOTES AND THE NOTE
     GUARANTEES WITHOUT GIVING EFFECT TO APPLICABLE PRINCIPLES OF CONFLICTS
     OF LAWS.

<Page>

              (20) REPAYMENT TO THE ISSUER. Any money deposited with the
     Trustee or any Paying Agent, or then held by the Issuer, in trust for
     the payment of the principal of, premium and Liquidated Damages, if any,
     or interest on any Note and remaining unclaimed for two years after such
     principal, and premium or Liquidated Damages, if any, or interest has
     become due and payable shall be paid to the Issuer on its request or (if
     then held by the Issuer) shall be discharged from such trust; and the
     Holder of such Note shall thereafter look only to the Issuer for payment
     thereof, and all liability of the Trustee or such Paying Agent with
     respect to such trust money, and all liability of the Issuer as trustee
     thereof, shall thereupon cease.