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                          KEY EMPLOYEE STOCK AGREEMENT

This Key Employee Stock Agreement ("Agreement") made this __ day of ____, 1999
by and among ADVANCED SWITCHING COMMUNICATIONS, INC. ("ASC" or "Company") and
_______ ("Key Employee").

                                    RECITALS

        A. Key Employee is employed by ASC and simultaneously herewith will
become the holder of _____ shares of ASC common stock as evidenced by
Certificates Number ___, a copy of which is attached hereto and a condition of
ownership is that Key Employee execute this Agreement.

        B. As of the date hereof, ASC has __________ common shares authorized of
which ________ or more have been previously issued, and Company anticipates
issuing additional shares to its employees and to others from time to time.

        NOW, THEREFORE, the parties agree as follows:

        1.      DEFINITIONS

                (a)     "day" or "days" shall mean calendar days but if the last
day of any period of time to be computed under this Agreement for the giving of
notices or otherwise shall be a Saturday, Sunday or legal holiday in the United
States, such period shall be extended to the next succeeding business day.

                (b)     "employed by Company" shall include employment with
Company or any affiliates of Company.

                (c)     "for cause" shall have the same meaning as that term has
in that certain Employment Agreement between the Key Employee and the Company of
even date herewith ("Employment Agreement").

                (d)     "Key Employee" shall include, in the case of incapacity
of death and where the context so requires, the executor, administrator,
guardian, or personal representative of Key Employee, and any transferee of the
Shares who becomes a transferee in accordance with this Agreement.

                (e)     "Shares" means the Shares of Company as described above,
and (i) any shares of the Company acquired by Employee after this date from any
source, (ii) any subdivision of such Shares, (iii) the payment of a dividend in
Shares with respect to


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such Shares, and\or (iv) any other securities issuable with respect to such
Shares without consideration or into which such Shares are transformed as the
result of a merger, consolidation, or recapitalization.

                (f)     "subsidiary" or "affiliate" means any company controlled
by or under common control as Company.

                (g)     "Transfer" shall mean any sale, assignment, bequest,
donation, pledge, encumbrance, or other transfer.

                (h)     "without cause" shall have the same meaning as that term
has in the Employment Agreement.


        2.      LEGEND ON CERTIFICATE

        The certificate representing the Shares will bear a legend indicating
(i) that the Shares have not been registered under the Securities Act of 1933 or
the securities laws of any jurisdiction, and may not be sold or offered for sale
in the absence of such registration or an exemption therefrom, and (ii) that any
Transfer of the Shares is subject to this Agreement, and will not be recognized
by Company unless made in compliance with this Agreement.

        3.      RESTRICTIONS ON TRANSFER

        Key Employee shall not Transfer any of the Shares except as permitted or
required by this Agreement, and any Transfer that does not comply with this
Agreement shall be void.

        4.      COMPANY'S REPURCHASE RIGHTS

        If Key Employee is terminated by the Company for cause or if the
Employee shall commit, or permit, an unauthorized Transfer of the Shares or
shall terminate employment without cause at any time, Company shall be entitled
to repurchase all, but not less than all, of the Shares then owned by Key
Employee. If such purchase is made within twelve (12) months of the date hereof,
the purchase price shall be the greater of (i) the price paid for the Shares by
Key Employee, or (ii) one dollar ($1.00). Thereafter, the purchase price shall
be the greater of (i) the price paid for the Shares by Key Employee, or (ii) the
book value of Company as of the date of termination of his employment or the
date of the attempted transfer. To exercise its repurchase rights, Company shall
notify Key Employee that it is exercising


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such rights and shall thereafter tender payment for the Shares, whereupon Key
Employee shall promptly tender to Company the certificate(s) representing the
Shares. Company shall exercise its repurchase rights if at all within eighteen
(18) months next following the date on which Key Employee ceases to be employed
by Company or the date when the Company becomes aware of an attempt to Transfer
by Key Staff Employee, as the case may be, after which such rights shall
terminate. Employee acknowledges that the stock issuance to Employee is intended
by Employer (i) to be an incentive, in addition to the fair value of Employee's
services which is otherwise being paid to employee in salary for the employment,
and (ii) to promote stability in Employer by retaining personnel for a minimum
of a year. Employee also acknowledges that the valuation for the twelve (12)
month period above is fair and in light of the intentions of the Employer.

        5.      PUT AND CALL RIGHTS

        (a)     If Key Employee dies, becomes substantially and permanently
disabled, or is terminated other than for cause, (i) Key Employee shall have the
right to cause Company to repurchase all but not less than all of the Shares
then owned by Key Employee, and (ii) Company shall have the right to repurchase
all but not less than all of the Shares then owned by Key Employee, such rights
in either case to be exercised within 180 days from the date of death,
determination of such disability or termination, and in either case for a
purchase price equal to the Fair Market Value of the Shares, determined as of
the last day of the month preceding the date on which either Key Employee or
Company exercises his or its rights under this Section 5(a).

        (b)     To exercise its rights hereunder, Company shall give Key
Employee a written notice of its intent to exercise its rights ("Call Notice"),
which notice shall constitute an unconditional and irrevocable offer to
repurchase the Shares, and which shall contain Company's determination of the
Fair Market Value, as defined below, of the Shares. If Key Employee does not
notify Company that he contests the Fair Market Value stated in Call Notice
within twenty (20) days after Company has given such Call Notice, such Fair
Market Value shall be final, and on or before forty (40) days from the date on
which Company has given such Call Notice, (i) Company shall pay the Fair Market
Value of the Shares to Key Employee in cash, and (ii) Key Employee shall give to
Company the certificate(s) representing the Shares, properly endorsed for
transfer.

        (c)     To exercise his rights hereunder, Key Employee shall give
Company a written notice of its intent to exercise its


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rights hereunder ("Put Notice") to that effect, which notice shall constitute an
unconditional and irrevocable offer to sell the Shares to Company. Within sixty
(60) days after receiving the Put Notice, Company shall notify Key Employee of
its determination of the Fair Market Value of the Shares. If Key Employee does
not notify Company that he contests the Fair Market Value as determined by
Company within twenty (20) days after receiving such notice of determination,
such Fair Market Value shall be final, and on or before forty (40) days from the
date on which Company has sent Key Employee the notice of determination of Fair
Market Value, (i) Company shall pay the Fair Market Value of the Shares to Key
Employee, and (ii) Key Employee shall upon receipt of such note give to Company
the certificate(s) representing the Shares, properly endorsed for transfer.

        (d)     Fair Market Value, for purposes of this section 5, shall be
determined initially by Company's Board of Directors, who may but shall not be
obligated to seek or rely upon the opinions of financial or investment advisors.
If Key Employee notifies Company within the time limits set forth above that he
contests such determination, the Company shall appoint an appraiser
("Appraiser"), acceptable to Key Employee, who shall determine the Fair Market
Value and whose determination shall be final and binding. The Appraiser (i)
shall have the requisite experience and knowledge to evaluate Company and
determine its Fair Market Value and (ii) shall have no prior professional
relationship with either party.

        (e)     The Appraiser shall determine the Fair Market Value of the
Shares, using such procedures as he deems necessary. Company and Key Employee
shall provide the Appraiser with full access to financial and other data, all of
which the Appraiser shall hold in confidence to the extent reasonably requested
by Company. If the Fair Market Value as determined by the Appraiser is 115
percent of the Fair Market Value as initially determined by Company, or less,
Key Employee shall pay the entire cost of the appraisal (including fees of the
Appraiser), and if the Fair Market Value as determined by the Appraiser is
greater than 115 percent of the Fair Market Value as determined by Company,
Company shall pay the entire cost of the appraisal (including such fees).

        (f)     The Fair Market Value of the Shares for all purposes under this
section 5, regardless of who determines it, shall be determined on the basis at
which the entire Company would change hands between a willing buyer and a
willing seller, each having knowledge of all relevant facts and neither being
under any compulsion to buy or sell, with no premium or discount attributed


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to the fact that the Shares represent either a control or minority position in a
closely-held company.

        (g)     Notwithstanding anything set forth herein, in the event the
Company shall purchase the Shares following the a Call Notice under item (ii) of
subparagraph a above, then the Key Employee shall have the right for the
Revaluation Period, as defined below, to again request the Company determine the
Fair Market Value. Upon receipt of such notice, the Company's Board of Directors
shall determine Fair Market Value, who may but shall not be obligated to seek or
rely upon the opinions of financial or investment advisors. Fair Market Value
shall be as of the date of the receipt of the request and thereafter the Company
shall pay Key Employee the difference, if any, between the Fair Market Value
determined in connection with the Call Notice and the Fair Market Value
determined under this subparagraph. The Revaluation Period shall commence with
the date of death, determination of such disability or termination, and shall
extend for the same number of months as the Key Employee was employed by the
Company, but for a maximum of eighteen (18) months. The Fair Market Value
determined under this subparagraph shall be final, and it shall pay the
difference in the Fair Market Value to Key Employee in four (4) equal quarterly
payments, without interest, or upon such other terms as may be agreed upon
between the Company the Key Employee, and Key Employee shall have no further
rights under this Agreement.

        6.      TRANSFERS BY OPERATION OF LAW

        If Key Employee (i) files a voluntary petition under any bankruptcy or
insolvency law, or a petition for the appointment of a receiver, or makes an
assignment for the benefit of creditors; or (ii) Key Employee is subjected
involuntarily to such a petition or assignment, or a third party obtains an
attachment or other legal or equitable interest in any of the Shares and such
involuntary petition, assignment, or attachment is not discharged within 20 days
after it has been filed; or (iii) the Shares are otherwise subject to a Transfer
by operation of law (other than death), Company shall have the right to purchase
all such Shares pursuant to the procedures set forth in section 5 above.

        7.      TAKE ALONG

        The Key Employee acknowledges that value of Key Employee's interest in
ASC is enhanced by the control over the Company's affairs exercised by the
holders of the majority of the common stock of the Company. Therefore, in
addition to all other



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provisions of this Agreement, in the event a sale or exchange of the common
stock of ASC is approved by the holders of the majority of the common stock, Key
Employee will vote for and participate in such sale or exchange upon the same
terms and conditions.

        8.      FIRST RIGHT OF REFUSAL

        Definitions. The following terms shall have the following meanings
whenever used in this Agreement:

        (a)     "Bona Fide Offer" shall mean a legally enforceable offer in
writing, made and signed by an offeror or offerors who is (or who are) not an
Affiliate, as defined below, of the Offering Key Employee and who is a person or
persons or entity or entities financially capable of carrying out the terms of
such Bona Fide Offer.

        (b)     "Registered Notice" shall mean notice sent by registered or
certified mail, return receipt requested, and first-class postage prepaid; and,
if such Registered Notice is sent with respect to a Bona Fide Offer (as provided
for below), such Registered Notice shall contain a true and complete copy of the
Bona Fide Offer, setting forth the price and all terms and conditions, with the
name(s), address(es) (both home and office) and business(es) or other
occupation(s) of the offeror or offerors. Any notice which does not contain all
such requisite information shall not be considered a "Registered Notice" for the
purposes hereof.

        (c)     "Relative," as it relates to any person or entity, shall mean
any parent, spouse, brother or sister, or natural or adopted lineal descendant
or spouse of such descendant of such person, and any proprietorship,
corporation, partnership, trust or other entity in which such person, or other
Relative may have an equity interest or in which such person, entity or other
Relative is a proprietor, partner, officer, director, employee, consultant,
independent contractor, coventurer, employer, agent, representative, settlor or
beneficiary.

        Receipt of Bona Fide Offer. In the event that a Key Employee shall
receive a Bona Fide Offer to purchase all (but not less than all) of such Key
Employee's Shares and in the further event that such Key Employee shall desire
to accept such Bona Fide Offer, such Key Employee shall promptly send Registered
Notice to the Company, offering to sell the Shares to the Company. The Company
shall then have such rights and privileges, for the prescribed time periods, as
are set forth in herein.


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        Procedure. Whenever a Bona Fide Offer to purchase Shares has been
received, and Registered Notice of the Bona Fide Offer has been sent by the Key
Employee, the following procedure shall be complied with: For a period of sixty
(60) days from the receipt of such Registered Notice, the Company shall have the
right, at the Company's sole option, to purchase all (but not less than all) of
the Shares offered as aforesaid upon the same terms as a Call of the Shares and
to send Key Employee a Call Notice as described above. If the Company shall
elect not to Call the Shares (for reasons other than the Key Employee's default
hereunder), within the prescribed time periods, all of the Shares covered by the
Bona Fide Offer, the Key Employee shall have the right to accept the Bona Fide
Offer in whole (but not in part) and to sell such Shares, subject at all times
to all of the provisions and restrictions of this Agreement, but only in strict
accordance with all of the provisions of the Bona Fide Offer and only if the
sale is fully consummated within one hundred twenty (120) days after the mailing
of the Registered Notice. In the event that such sale is not fully consummated
within one hundred twenty (120) days after the mailing of the Registered Notice,
the provisions of this paragraph 8 must again be complied with by the Key
Employee before the Key Employee may sell the Shares which are the subject of
the Bona Fide Offer pursuant to this paragraph 8.

        9.      TRANSFERS IN VIOLATION OF THIS AGREEMENT

        Company may refuse to permit a transferee of any or all of the Shares,
including without limitation a pledgee or secured party, who has acquired Shares
in any manner other than as provided for in this Agreement, to vote the Shares,
may decline to issue dividends with respect to the Shares, and may decline to
recognize the transferee as a stockholder with respect to the Shares for any
purpose.

        10.     ABSENCE OF OBLIGATIONS

        Nothing in this Agreement shall confer on Key Employee any right to
continue on Company's employment for any stated period of time.

        11.     NOTICES

        Any notice permitted or required to be given under this Agreement shall
be in writing, shall be sent by overnight courier service, or by telecopy
followed immediately by first class mail, or by any other means reasonably
certain to result in overnight



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delivery, and shall be effective when given. Any notice given to Company shall
be delivered to its principal place of business in the United States, to the
attention of its chief executive officer. Any notice given to Key Employee or to
any transferee of the Shares shall be delivered to his/her last known address as
shown by Company's records.

        12.     GOVERNING LAW

        This Agreement shall be construed under and governed in accordance with
the laws of the Commonwealth of Virginia.

        13.     AMENDMENTS

        This Agreement may be modified, amended, or supplemented only by an
instrument in writing signed by the parties.

        Executed as of the date set forth above:



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                             ADVANCED SWITCHING COMMUNICATIONS,
                               INC., a Delaware corporation

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


                             KEY EMPLOYEE


                             -----------------------------------
                             Name:
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