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                                                                  Exhibit 10.16A

                   KEY EMPLOYEE EMPLOYMENT AGREEMENT ADDENDUM

This ADDENDUM to the KEY EMPLOYEE EMPLOYMENT AGREEMENT (executed on June 21,
1999) ("Agreement") entered into this ______ day of February, 2001 by and
between ADVANCED SWITCHING COMMUNICATIONS, INC., a Delaware corporation
("Employer") and Harry D'Andrea ("Employee"), an individual resident of Potomac,
MD is effective as of the 31st day of December 2000.

SECTION 3 e is hereby added as follows:

STOCK OPTIONS: A new hire stock option grant of 180,000 shares of ASC's common
stock is awarded with Board approval subject to the Second 1998 Nonqualified
Stock Option Plan. The vesting period for the options is 45,000 (25%) shares on
June 21, 2000 which is the 1-year anniversary of the effective date of the
grant, 45,000 (25%) shares on June 21, 2001, 45,000 (25%) shares on June 21,
2002, and the remaining 45,000 (25%) shares on June 21, 2003 provided the
employee is employed on these dates. In case of Change of Control as described
within the Stock Option Plan, all remaining options will fully vest.

SECTION 10 b is amended as follows:

b.       WITHOUT CAUSE: Without cause, the Employee may terminate this Agreement
upon two (2) weeks written notice to the Employer. In such event, Employee shall
continue to render his services up to the date of termination. Without cause,
the Employer may terminate this agreement at any time by paying one year's base
salary. Termination without cause by Employee shall mean the voluntary
termination of the Agreement by Employee. In such event, Employee, if requested
by the Employer, shall continue to render his services and shall be paid his
regular compensation, including any declared but unpaid bonuses, up to the date
of termination.

SECTION 10 c is hereby added as follows:

c.       CONSTRUCTIVE DISMISSAL: If one of the following events occur during
Employee's employment, then Employee may resign his ASC employment as being
constructively dismissed and receive payment of one year's base salary.

                  1.       If Employee is demoted from the position of Chief
                           Financial Officer (which title may be changed)
                           without his consent.

                  2.       If Employee's duties are materially reduced or the
                           level of his job responsibilities is materially
                           reduced without his consent.

                  3.       If Employee's base salary is reduced.

The remainder of the KEY EMPLOYEE EMPLOYMENT AGREEMENT dated June 21, 1999 will
remain in full force and effect. In WITNESS WHEREOF, the parties have executed
this Agreement on the day and year first above written.


EMPLOYER:                                  EMPLOYEE:
ASC, INC.
BY:  _______________________               BY:      _____________________

Title: _____________________



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


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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.

         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



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                  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.

         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:



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                  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,              Employee
Inc.

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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