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                                                                   Exhibit 10.19

                         EXECUTIVE SEPARATION AGREEMENT


        This Executive Separation Agreement (the Agreement) is entered into this
15th day of March, 2001, between Advanced Switching Communications, Inc. ("ASC")
and Lisa Adams (the "Executive") (sometimes collectively referred to as the
"Parties").

        WHEREAS:

        A. Executive was employed by ASC as a Sr. Vice President of Sales and by
mutual agreement, Executive's employment with ASC shall be deemed terminated
effective as of March 15, 2001 through Executive's resignation of employment.

        B. Company and Executive now desire to resolve all disputes, claims or
charges that may exist between them in any way relating to or arising out of
Executive's hire, employment, remuneration or termination from ASC, in
accordance with the terms and conditions set forth herein.

                                    AGREEMENT

        Now, therefore, in consideration of the mutual promises, conditions and
covenants set forth below, the parties hereto agree as follows:

1       Executive's Termination of Employment

        1.1     By virtue of ASC waiving the required two week notice period for
                resignation of employment, Executive hereby acknowledges that
                her employment with ASC shall be deemed terminated effective as
                of March 15, 2001 and she is providing a resignation letter
                simultaneously with the execution of this Agreement (the
                Termination Date).

2       Separation Payments

        2.1     ASC shall provide Executive with separation payments equal to
                her base pay less statutory withholdings on ASC's normal payroll
                schedule until September 15, 2001, (the Separation Payments)
                once this agreement is irrevocable.

        2.2     Vacation pay accrued but not taken by Executive as of the
                Termination Date shall be paid to Executive following March 15,
                2001.

        2.3     The Separation Payment shall be paid by check made payable to
                Executive and shall be mailed to Executive at 6521 NW 39th
                Terrace, Boca Raton, FL 33496 unless ASC is otherwise notified
                in writing.


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3       Medical Insurance and Other Benefits

        3.1     Executive acknowledges that, subject to her rights under the
                CONSOLIDATED OMNIBUS BUDGET RECONCILIATION ACT (COBRA), she may
                continue to remain covered under ASC's medical and dental
                insurance plans at her own expense for up to eighteen (18)
                months. During the six month period from March 15, 2001 through
                September 15, 2001 that ASC is providing separation payments as
                described in article 2.1 above, ASC contemporaneously will
                underwrite the costs of Executive's COBRA coverage if she elects
                to continue her health insurance coverage under COBRA.

        3.2     As of the termination date, Executive's vested options as of
                March 15, 2001 for 125,000 shares of company common stock shall
                be exercisable in accordance with Exhibit A attached hereto. All
                other options previously granted to employee shall expire and
                terminate on the Termination Date.

        3.3     ASC is willing to reimburse you for reasonable business expenses
                incurred by you on behalf of the company within 14 days after
                they have been submitted as long as they have been submitted
                within 30 days of your termination date and are submitted in
                accordance with company policy including, any appropriate
                documentation that may reasonably be requested by the company.

4       No Other Amounts Owed

        4.1     The payments and items provided for in articles 2 and 3 above
                shall constitute the entire, maximum, and only financial or
                other obligation of ASC to Executive under this Agreement or
                otherwise.

        4.2     Executive expressly acknowledges and agrees that the payments
                provided for in this Agreement are in lieu of and exceed any
                other compensation or payments to which she may be entitled by
                virtue of her employment with and/or termination from ASC.

5       No Admission

        5.1     Neither the payment of the above-referenced amounts, nor the
                execution or performance of any terms of this Agreement shall
                constitute or be construed as an admission of any liability
                whatsoever by ASC to Executive.

6       Employment Reference and Nondisparagement

        6.1     If ASC receives any inquiries from prospective future employers
                of Executive, ASC shall confirm only dates of employment and
                position held.



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        6.2     ASC, through the officers named below, and Executive will not
                orally or in writing defame, criticize or willfully disparage,
                or in any manner undermine the reputation of the other, and in
                the case of ASC, includes any subsidiary or affiliated
                corporation of ASC itself, or any employee, officer or director
                of the Company or any subsidiary or affiliate of the Company,
                except as required by compulsion of law to truthfully testify. A
                disparaging statement is any communication, oral or written,
                which is intended, or would tend, to cause the recipient of the
                communication to question the business condition, quality of
                products and services, legal compliance, integrity, competence,
                fairness or good character of ASC or the person to whom the
                communication relates. The ASC officers bound by this provision
                are Harry D'Andrea, Asghar Mostafa, Larry Kraft, Robert Stewart,
                Jim Loehndorf, Ron Westernik, Jeffrey Range, Glen Hunt, Alex
                Dobson, and Tom Ma.



7       Release

        7.1     For the valuable consideration set out in this Agreement, the
                receipt and adequacy of which are hereby acknowledged, and
                except as specifically set forth in paragraph 7.5 below:

                7.1.1   Executive, on behalf of herself, and each of her heirs,
                        executors, administrators, successors and assigns, does
                        hereby release and forever discharge ASC, and any of its
                        parent companies, subsidiaries, affiliates, divisions,
                        predecessors, successors, agents, representatives,
                        officers, directors, employees, shareholders, heirs,
                        assigns, past and present, and their attorneys, and all
                        persons acting by, through, under or in concert with
                        them or any of them (the ASC Releasees), of and from any
                        and all manner of action or actions, cause or causes of
                        action, in law or in equity for indemnity or otherwise,
                        suits, grievances, arbitrations, complaints, debts,
                        liens, contracts, agreements, promises, liabilities,
                        claims, demands, damages, losses, costs, or expenses, of
                        any nature whatsoever, known or unknown, fixed or
                        contingent (hereinafter called Claims), which the
                        Executive now has or may hereafter have against the ASC
                        Releasees, by reason of any matter, cause or thing
                        whatsoever occurring or existing up to and inclusive of
                        the Effective Date of this Agreement, including but not
                        limited to those claims arising out of:

                        7.1.1.1 the contract of employment between Executive and
                                ASC;

                        7.1.1.2 the termination of the contract of employment
                                between Executive and ASC;

                        7.1.1.3 Executive's loss of position, status, future job
                                opportunity, or reputation;

                        7.1.1.4 losses related to the timing of Executive's
                                conclusion of employment or the manner in which
                                it was effected;



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                        7.1.1.5 the loss of benefits, benefits eligibility, or
                                benefits insurance coverage previously provided
                                to Executive by ASC or available to Executive in
                                connection with her employment with ASC ,
                                including but not limited to benefits, benefits
                                eligibility or benefits insurance coverage
                                relating to or arising from the following
                                matters: medical fees, charges, or expenses;
                                extended health fees, charges, or expenses;
                                dental fees, charges, or expenses; sick pay or
                                sick leave; life insurance (including life
                                insurance conversion privileges); 401(k)
                                contributions; pension contributions or
                                benefits; short term disability; long term
                                disability; the Stock Option Plan; and any other
                                type of loss or damages.

        7.2     Without limiting the generality of the foregoing, the Claims
                released herein include any Claims arising out of, based upon or
                in any way related to:

                7.2.1   any property, contract or tort claims, including
                        wrongful discharge, breach of employment contract,
                        breach of the covenant of good faith and fair dealing,
                        retaliation, intentional or negligent infliction of
                        emotional distress, tortious interference with existing
                        or prospective economic advantage, negligence,
                        misrepresentation, breach of privacy, defamation, loss
                        of consortium, breach of fiduciary duty, violation of
                        public policy or any other common law claim of any kind;

                7.2.2   any violation or alleged violation of Title VII of the
                        CIVIL RIGHTS ACT OF 1964, as amended, the AGE
                        DISCRIMINATION IN EMPLOYMENT ACT, as amended, the OLDER
                        WORKERS BENEFIT PROTECTION ACT OF 1990, the EQUAL PAY
                        ACT, as amended, the FAIR LABOR STANDARDS ACT, the
                        EMPLOYEE RETIREMENT INCOME SECURITY ACT, the AMERICANS
                        WITH DISABILITIES ACT, the CALIFORNIA FAIR EMPLOYMENT
                        AND HOUSING ACT, the CALIFORNIA LABOR CODE, the
                        CALIFORNIA UNEMPLOYMENT INSURANCE ACT, the CALIFORNIA
                        WORKERS COMPENSATION ACT, the CIVIL RIGHTS ACT OF 1866,
                        the CONSOLIDATED OMNIBUS BUDGET RECONCILIATION ACT,
                        CALIFORNIA LABOR CODE SECTION 1102.5, the CALIFORNIA
                        FAMILY RIGHTS ACT, OR the FAMILY AND MEDICAL LEAVE ACT
                        OF 1993;

                7.2.3   any claims for severance pay, bonus, sick leave,
                        vacation or holiday pay, life insurance, health,
                        disability or medical insurance or any other fringe
                        benefit; and

                7.2.4   any claim relating to or arising under any other local,
                        state or federal statute or principle of common law
                        (whether in contract or in tort) governing the
                        employment of individuals, discrimination in employment
                        and/or the payment of wages or benefits.

        7.3     IN ACCORDANCE WITH THE OLDER WORKERS BENEFIT PROTECTION ACT OF
                1990, EXECUTIVE SHOULD BE AWARE OF THE FOLLOWING:

                7.3.1   You have the right to consult with an attorney before
                        signing this Agreement;

                7.3.2   You have twenty-one (21) days to consider this
                        Agreement; and



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                7.3.3   You have seven (7) days after signing this Agreement to
                        revoke this Agreement, and this Agreement shall not be
                        effective until that revocation period has expired. ASC
                        reserves the right to withdraw this Agreement prior to
                        its acceptance by you.

                        Executive agrees that if she signs this Agreement but
                        then chooses to revoke this Agreement pursuant to
                        subparagraph 7..3.3 above, this Agreement and all of its
                        terms shall immediately terminate including payments
                        thereunder.

        7.4     Executive acknowledges that she has been advised of and is
                familiar with the provisions of the CALIFORNIA CIVIL CODE
                SECTION 1542 which provides as follows:

                A GENERAL RELEASE DOES NOT EXTEND TO CLAIMS WHICH THE CREDITOR
                DOES NOT KNOW OR SUSPECT TO EXIST IN HER FAVOR AT THE TIME OF
                EXECUTING THE RELEASE, WHICH IF KNOWN BY HER MUST HAVE
                MATERIALLY AFFECTED HER SETTLEMENT WITH THE DEBTOR.

                Executive, being aware of said Code section, hereby expressly
                waives any rights she may have thereunder, as well as under any
                other statutes or common law principles of similar effect.

        7.5     Notwithstanding anything to the contrary set forth above, the
                Parties expressly acknowledge and agree that the releases
                contained in this article 7 are not intended to apply to:

                7.5.1   the obligations and representations of the Parties set
                        forth in this Agreement;

                7.5.2   Executive's rights, if any, to indemnity pursuant to
                        CALIFORNIA LABOR CODE 2802 and/or the CALIFORNIA
                        CORPORATIONS CODE 317.

        7.6     Executive represents and warrants that there has been and there
                shall be no assignment or other transfer of any interest in any
                claim that she may have against ASC Releasees, or any of them.

        7.7     ASC agrees to release Executive from any and all civil claims
                arising out of or in the course of her employment with ASC with
                the exception of a release of claims constituting criminal
                conduct. ASC further acknowledges that Executive's only
                post-employment restrictions are contained within this Executive
                Separation Agreement and that all restrictive covenants and
                agreements not to compete previously agreed to by parties
                (including those set forth in Section 7(b) of the September 22,
                2000 Employment Agreement between the parties) are hereby
                cancelled and unenforceable.

        7.8     The Parties agree that if any of them hereafter commences, joins
                in, or in any manner seeks relief against any of their
                respective releases through any suit arising out of, based upon,
                or relating to any of the Claims releases hereunder or in any
                manner asserts against their respective Releasees, or any of
                them, any of the claims released hereunder, then that party
                shall pay in addition to any other damages caused thereby, all
                attorneys' fees



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                and costs incurred by the affected Releasees in defending or
                otherwise responding to said suit or claim.

8       Solicitation of Employees

        8.1     Executive shall not under any circumstances solicit any
                employees of ASC, its subsidiaries, affiliates, divisions,
                predecessors, successors, agents, or representatives, to leave
                their employment for a period of twenty-four (24) months after
                the Termination Date.

        8.2     Executive shall not:

                8.2.1   solicit or otherwise encourage any employee or former
                        employee of ASC, it subsidiaries, affiliates, divisions,
                        predecessors, successors, agents, or representatives, to
                        file or assert any claim, charge or litigation against
                        ASC, its subsidiaries, affiliates, divisions,
                        predecessors, successors, agents, or representatives, in
                        any way relating to their employment; or

                8.2.2   voluntarily cooperate or otherwise offer assistance of
                        any kind to any employee or former employee of ASC, its
                        subsidiaries, affiliates, divisions, predecessors,
                        successors, agents, or representatives, in the
                        employees' or former employee's filing or prosecution of
                        any claim, charge or litigation against ASC, its
                        subsidiaries, affiliates, divisions, predecessors,
                        successors, agents, or representatives, in any way
                        relating to their employment, unless compelled to do so
                        by law.

9       Confidential Business Information and Tangible Property

        9.1     Executive shall hold in strictest confidence and not disclose,
                directly or indirectly, to any person, firm or corporation,
                without the express prior written consent of ASC, any trade
                secrets or any confidential business information, including, but
                not limited to, corporate planning, production, distribution or
                marketing processes; manufacturing techniques; customer lists or
                customer leads; marketing information or procedures; development
                work; work in process; financial statements or notes, schedules
                or supporting financial data; or any other secret or
                confidential matter relating to the products, sales or business
                of company, its subsidiaries, affiliates, divisions,
                predecessors, successors, agents, or representatives. Trade
                Secrets include information not generally known to the public
                regarding ASC's engineering capabilities, products, designs and
                prototypes in development.

        9.2     Executive agrees that within ten (10) days after the signing of
                this Agreement she shall deliver to ASC and shall not keep in
                her possession or deliver to anyone else, any and all company
                credit cards, notes, memoranda, specifications, financial
                statements, customer lists, product surveys, data, documents,
                other material containing or disclosing any of the matters
                referred to in paragraph 9.1 above and all other items of ASC
                property in her possession.



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        9.3     Executive acknowledges that any breach of the provisions of this
                article 9 by her shall cause irreparable injury to ASC, for
                which the available remedies at law shall not be adequate.
                Accordingly, in the event of any such breach or threatened
                breach of any provision of this article in addition to any other
                remedy provided by law or in equity, ASC shall be entitled to
                appropriate injunctive relief, in any court of competent
                jurisdiction, restraining Executive from any such actual or
                threatened breach of this article. Executive stipulates to the
                entry against Executive of any such temporary, preliminary or
                permanent injunction and agrees not to resist ASC's application
                for such equitable relief, except on the grounds that the acts
                or omissions alleged by ASC did not violate any of the
                provisions of this article.

10      Confidentiality

        10.1    In addition to the confidentiality provisions of article 9,
                Executive shall keep confidential and not disclose any of the
                terms of this Agreement to any person whatsoever (including, but
                not limited to, any current or former employees of ASC except
                her attorneys, tax advisors, immediate family and significant
                other) unless required to do so by law.

11      Miscellaneous

        11.1    This Agreement shall be governed by the law of the Commonwealth
                of Virginia, Company's principal place of business, without
                giving effect to Virginia's conflict of laws. The parties hereto
                agree that the proper venue for any dispute shall be the Fairfax
                County Circuit Court or the United States District Court for the
                Eastern District of Virginia, Alexandria Division and in the
                event that there is no other manner of service hereby appoint
                the Secretary of the Commonwealth of Virginia.

        11.2    This Agreement shall not be subject to attack on the ground that
                any or all of the legal theories or factual assumptions used for
                negotiating purposes are for any reason inaccurate or
                inappropriate.

        11.3    This Agreement represents the sole and entire agreement among
                the Parties and supersedes all prior agreements, negotiations,
                and discussions between the Parties hereto and/or their
                representatives. Any amendment to this Agreement must be in
                writing specifically referring to this Agreement and signed by
                duly authorized representatives of all of the Parties hereto.

        11.4    The Parties agree that the language of this Agreement shall not
                be construed for or against any particular party.

        11.5    The provisions of this Agreement are severable. If any provision
                is held to be invalid or unenforceable, it shall not affect the
                validity or enforceability of any other provision.

        11.6    Executive acknowledges and agrees that (i) ASC has advised her
                of her right to consult an attorney before signing this
                Agreement, (ii) she has consulted an attorney to the extent she
                deems advisable, (iii) she fully understands the provisions of
                this Agreement and their effect, and (iv) she is signing this
                Agreement voluntarily and free from duress.

        11.7    All monetary sums in this Agreement are in United States
                currency.



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        11.8    This Agreement may be executed in one or more counterparts, each
                of which is deemed an original, and all of which constitute one
                instrument.

        11.9    This Agreement shall be considered executed and delivered when
                either:

                11.9.1  an originally executed copy has been delivered to each
                        party; or

                11.9.2  when a facsimile of the Agreement evidencing this
                        signatures of all the Parties has been transmitted by
                        facsimile to each party and each party has acknowledged
                        receipt by return facsimile.

        11.10   The Effective Date of this Agreement shall be that date which is
                seven (7) days after the date on which Executive signs this
                Agreement, provided that Executive has not exercised her right
                to revoke this Agreement pursuant to subparagraph 7.3.3 above.


        Witness our signatures and seals as of the date written below.

Advanced Switching Communications, Inc.      Employee

By:                             (SEAL)                                    (SEAL)
   -----------------------------                    ----------------------
Title:                                              Lisa Adams

Date:                                               Date:
     ---------------------------                          ----------------------



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                                                                       Exhibit A

                    ADVANCED SWITCHING COMMUNICATIONS, INC.
                        NOTICE OF GRANT OF STOCK OPTIONS
                                    ADDENDUM


<TABLE>
<S>                                         <C>
Name of Participant:                        Lisa Adams
Address of the Participant:                 6321 NW 39th Terrace, Boca Raton, FL  33496
Non-Qualified Stock Option Grant No:        00000300
Date of Grant:                              September 25, 2000
Total Number of Shares Granted:             500,000
</TABLE>


Effective in accordance with the date your Executive Separation Agreement become
irrevocable, your stock grant No. 300, dated October 10, 2000 and referenced
above is amended such that you may exercise your vested options (125,000) at the
granted exercise price of $13.00 for up to six months after termination of your
employment on March 15, 2001. Therefore, all your unvested options will expire
upon termination of employment on March 15, 2001 and your vested options will
expire and all rights thereunder shall terminate on September 15, 2001 to the
extent they have not been exercised. All other provisions of the Advanced
Switching Communications, Inc. 2000 Stock Incentive Plan ("Plan") remain
unchanged and continue in full force and effect.

This amendment is made by the authority and with the approval of the Committee
appointed by the Board of Directors charged with administering the Plan.

By your signature and Advanced Switching Communications, Inc.'s signature by its
agent below, you agree that this option amendment and the initial option grant
are governed by the terms and conditions of Advanced Switching Communication's
2000 Stock Incentive Plan. Optionee represents that she is familiar with the
terms and conditions of the Grant Agreement and accepts the option and option
amendment subject to all the terms and conditions thereof. Optionee agrees to
accept as binding, conclusive and final all decisions or interpretations of the
Board of Directors of Advanced Switching Communications, Inc. upon any questions
arising under this agreement.

----------------------------------------------------------------

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For Advanced Switching Communications, Inc.               Date

-----------------------------------------     -------------------
Optionee                                                     Date


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