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                                                                   EXHIBIT 10.26


                 RETIREMENT AND SEPARATION AGREEMENT AND RELEASE
                 -----------------------------------------------

TO:  RICHARD W. BARCUS

     The purpose of this Retirement and Separation Agreement and Release
(hereinafter "Agreement") is to specify and confirm the terms of your retirement
and separation from employment with TELLIUM, INC. (hereinafter, "TELLIUM").

     1. You acknowledge that: (a) you were advised by TELLIUM to consult with an
attorney of your choosing before you signed this Agreement; and (b) you were
afforded sufficient opportunity to so consult with an attorney.

     2. You also acknowledge you were advised by TELLIUM, and understand, that:

     (a) You had twenty-one (21) days from your receipt of this Agreement to
consider and execute this agreement; and

     (b) You can revoke this Agreement by delivering written notice to TELLIUM,
attention E. Thomas Biehl, Director, Human Resources, within a period of seven
(7) days following the day on which you sign this Agreement (the "Revocation
Period"), and this Agreement shall not become effective or enforceable until
after the Revocation Period has expired; and

     (c) IN SIGNING THIS AGREEMENT, YOU ARE GIVING UP ANY AND ALL RIGHTS AND
CLAIMS WHICH YOU HAD, HAVE OR MAY HAVE AGAINST TELLIUM AND/OR ANY OF ITS PAST
AND PRESENT DIVISIONS, AFFILIATES, SUBSIDIARIES, BRANCHES, PARENTS,
PREDECESSORS, SUCCESSORS, ASSIGNS, OFFICERS, DIRECTORS, TRUSTEES,
ADMINISTRATORS, STOCKHOLDERS, EMPLOYEES, AGENTS, REPRESENTATIVES, ATTORNEYS,
INSURERS OR FIDUCIARIES, IN THEIR INDIVIDUAL OR REPRESENTATIVE CAPACITIES
(COLLECTIVELY REFERRED TO HEREINAFTER AS RELEASEES), including, but not limited
to, claims under the Age Discrimination in Employment Act of 1967, as amended,
29 U.S.C. 621 et seq. ("ADEA"); Title VII of the Civil Rights
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of 1964, as amended, 42 U.S.C. 2000e et seq. 1981a et seq. ("Civil Rights Act");
                                     -- ---        -- ---
the Civil Rights Act of 1991, as amended, 42 U.S.C. 1981a et seq. ("CRA of
                                                          -- ---
1991"); the Equal Pay Act, 29 U.S.C. 206(d) et seq. ("EPA"); the Americans with
Disabilities Act, 42 U.S.C. 12101 et seq. ("ADA"); the Federal Family and
Medical Leave Act, 29 U.S.C. 2601 et seq. ("FMLA"); the Fair Labor Standards Act
                                  -- ---
29 U.S.C. 201 et seq. ("FLSA"); the Employee Retirement Income Security Act of
1974, as amended, 29 U.S.C. 1001 et seq. ("ERISA"); the New Jersey Law Against
                                 -- ---
Discrimination, N.J.S.A. 10:5-1 et seq. ("LAD"); the New Jersey Family Leave
                -------         -- ---
Act, N.J.S.A. 34:11B-1 et seq. ("FLA"); the New Jersey Conscientious Employee
     -------           -- ---
Protection Act, N.J.S.A. 34:19-1 et seq. ("CEPA") (also known as the
whistleblower Act); the New Jersey Workers' Compensation Act ("WCA"), N.J.S.A.
34:15-1 et seq.; the New Jersey State Wage and Hour Law, N.J.S.A. 34:11-4.1 et
seq. ("W-H Law"); the New Jersey Political Activities of Employees law, N.J.S.A.
19:34-27 et seq. ("PAAE); the New Jersey Jury Duty Employment Protection law,
N.J.S.A. 2B:20-17 ("JDE"); the New Jersey Lie Detector Test law, N.J.S.A. 2C:40A
("LDT"); the New Jersey Tobacco Use law, N.J.S.A. 34:6B-1 et seq. ("TUL"); the
New Jersey Genetic Testing law, N.J.S.A. 17B:30-12, et seq. ("GT"); and/or any
and all other federal, state or local statutes, laws, rules and regulations
pertaining to employment, as well as any and all claims under the state contract
or tort law.

     3. You acknowledge and agree that your employment with TELLIUM will
terminate effective December 15, 2001 (month/day/year) (referred to hereinafter
as the "Retirement Separation Date").

     4. TELLIUM agrees to pay you six (6) months of severance, at your regular
annual salary rate of $200,000.00, which will be paid to you on our semi-monthly
payroll cycle. TELLIUM also agrees to pay you in 2002 a payment for any unused
but earned vacation days. In the event that TELLIUM declares a bonus for the
time period of 2001 and before to executive management, you



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will be paid in the same manner and in the same amount as if you were still
President and COO. TELLIUM agrees to accelerate the vesting of the company match
portion of your 401-K retirement account so that all company matching amounts
are fully vested

     5. TELLIUM will continue your family's health insurance coverage for a
period of twelve months following your Retirement and Separation date as stated
in paragraph three, after which time you will be eligible for continued coverage
through COBRA.

     6. TELLIUM agrees to buy back a number of your currently vested restricted
shares that are subject to the loan from TELLIUM at the fair market value on or
about January 3, 2002 is no longer subject to cancellation or revocation by you.
The number of shares shall be sufficient to extinguish the outstanding note and
interest on the currently vested shares and any accelerated vesting of shares as
provided in the next sentence of this paragraph of this agreement. TELLIUM also
agrees that TELLIUM will accelerate the vesting of a number of your unvested
restricted shares equal to the number of shares the company is buying back as
described above in this paragraph. Any remaining unvested shares will be
repurchased by TELLIUM pursuant to the existing agreements between you and
TELLIUM.

     7. TELLIUM agrees to pay directly to Lipman, Selznick & Witkowski for the
purpose of completing your 2001 federal and state income tax returns. TELLIUM
agrees to reimburse reasonable and customary expenses for moving your household
goods to Virginia. TELLIUM agrees to assume all responsibilities and liabilities
for your Little Silver Townhouse, including utilities. TELLIUM agrees that you
will be allowed to keep your Palm Pilot device, your cell phone and your laptop
computer and associated accessories. TELLIUM agrees to reimburse you for any
usual and customary business expenses incurred on behalf of TELLIUM while you
were an employee and which have not yet been reimbursed.


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     8. In the event that any payment or benefit that is provided for hereunder
is determined or alleged to be subject to an excise or similar purpose tax or
other comparable federal, state, or local tax laws or any interest or penalties
incurred by you with respect to such excise or similar purpose tax TELLIUM shall
pay to you such additional compensation as is necessary to place you in the same
after-tax position that you would have been in had no such tax, interest, or
penalty been paid or incurred taking into account any federal, state, and local
income taxes or Excise Tax, payable by you as a result of the receipt of such
additional compensation (a "Gross-Up Payment").

     9. You understand and agree that the payments and/or benefits specified in
paragraphs 4, 5, 6 and 7 of this Agreement exceeds any payments and/or benefits
provided in any employment agreement, verbal or written, as well as any
employment or personnel policies, procedures or handbooks, which may be
applicable to you.

     10. TELLIUM confirms and agrees that you will be indemnified on a "pay on
behalf of" basis, to the fullest extent provided by TELLIUM's Certificates of
Incorporation and Bylaws, as provided by the General Corporations Law of the
State of Delaware, and TELLIUM's Executive Liability Insurance programs against
all liabilities and expenses with respect to all acts and omissions arising out
of your service as an officer of TELLIUM and/or it's subsidiaries

     11. The parties understand and agree that this Agreement is intended to
provide amicable terms for your retirement and separation from employment with
TELLIUM and that this Agreement is not an admission of any wrongdoing or
liability by TELLIUM or by you. You and TELLIUM agree not to disparage each
other in any way.

     12. For and in consideration of the payments made by TELLIUM pursuant to
paragraphs 4, 5, 6 and 7 of this Agreement and other good and valuable
consideration, you hereby release and forever discharge RELEASEES of and from
any and all actions, causes of action, suits, charges,


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complaints, grievances, claims, obligations, costs, losses, damages, injuries,
attorneys' fees, debts, dues, sums of money, accounts, reckonings, bonds, bills,
specialties, covenants, contracts, controversies, agreements, promises,
variances, trespasses, judgments, extents, executions, claims, demands, and/or
other legal responsibilities of any form whatsoever (collectively referred to
hereinafter as "claims"), including, but not limited to, any claims in law,
admiralty, equity, contract, tort, or any claims arising out of your employment
with and separation from TELLIUM including, but not limited to, any claims
arising under the ADEA, Title VII, the Civil Rights Act, the CRA of 1991, the
EPA, the ADA, the FMLA, the FLSA, ERISA, the LAD, the FLA, the CEPA, the WCA,
the W-H Law, the PAE, the JDE, the LDT, the TUL, the GT and/or any and all other
federal, state or local statutes, laws, rules, and regulations pertaining to
employment, as well as any and all claims under state contract or tort law or
public policy against RELEASEES, whether known or unknown, unforeseen,
unanticipated, unsuspected or latent which you, your heirs, executors,
administrators, successors and assigns ever had, now have or hereafter can,
shall or may have for, upon or by reason of any matter, cause or thing from the
beginning of the world to the date of execution of this Agreement, except to the
extent that any such claim concerns an allegation that TELLIUM has failed to
comply with any obligations created by this Agreement.

     13. In addition to your separately enforceable obligations under any
existing intellectual property and non-disclosure agreement(s) and at common
law, YOU WILL NOT, without the prior written consent of TELLIUM and for a period
of 12 (twelve) months after execution of this Agreement, directly or indirectly:

     (a)  engage in any employment or other business activities that resemble or
          are competitive with TELLIUM's business activities about which you
          gained any proprietary or confidential information; or


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     (b)  hire, employ, or attempt to hire or employ, any TELLIUM employee, or
          otherwise solicit, request, entice or induce any such employee to
          leave his or her employment, for the purpose of engaging in any
          business activity that is competitive with the business activities of
          TELLIUM.

     You recognize and agree that such restrictions are necessary and reasonable
to protect TELLIUM's highly confidential and proprietary information, valuable
goodwill, customer relationships and competitive position.

     You agree that during this 12 (twelve) month period after the execution of
this Agreement, you will inform TELLIUM of the identity of any new employer (or
the nature of self-employment) and of your new title and job description.
Further, you will provide such information as TELLIUM may form time-to-time
request, during this twelve month period, to determine your compliance with the
terms of this Agreement.

     The term "indirectly" as used in this Agreement includes acting as a paid
or unpaid director, officer, agent, representative, employee of, or consultant
or independent contractor to any enterprise, or acting as a proprietor of an
enterprise, or holding any direct or indirect participation in any enterprise as
an owner, partner, limited partner, joint venturer, shareholder, or creditor.

     14. You understand and agree that the existence and terms and conditions of
this Agreement are to be private and confidential, and you agree not to disclose
the existence or any of the terms and conditions of this Agreement to any person
except your immediate family, attorney, tax


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advisor or taxing authorities, or as otherwise required by law. You further
agree to immediately instruct your immediate family, attorney, tax advisor and
taxing authorities not to disclose the existence or terms and conditions of this
Agreement to anyone. In the event of any action concerning this Agreement, same
shall be submitted to the Court under seal to protect the confidentiality
thereof.

     15. This Agreement constitutes the entire agreement between you and TELLIUM
as to the subject matter contained in this Agreement, and supersedes all prior
understandings and agreements, if any between the parties. This Agreement may
not be changed except by an instrument in writing signed by the parties.

     16. The interpretation of this Agreement and the rights of the parties
under this Agreement shall be governed by the substantive laws of the State of
New Jersey.

     17. This Agreement may be signed in counterparts and, if so signed, this
Agreement shall have the same force and effect as if signed at the same time.

     18. You acknowledge that: (a) you have read and understand all of the
provisions of this Agreement and are fully aware of the content and legal effect
of this Agreement: (b) you are entering into this Agreement freely, voluntarily
and of your own will and that RELEASEES have not made any representation,
statement, promise, inducement, threat or suggestion to induce you to sign this
Agreement, except the statements expressly set forth herein; and (c) you have
not relied on any representation or statement not set forth in this Agreement

     BY SIGNING THIS RETIREMENT AND SEPARATION AGREEMENT AND RELEASE, I, RICHARD
     BARCUS, ACKNOWLEDGE THAT I HAVE READ IT, UNDERSTAND IT AND AGREE TO BE
     BOUND BY ALL OF ITS TERMS. FURTHER, IF I SIGN AND RETURN THIS AGREEMENT TO
     TELLIUM LESS THAN 21 DAYS AFTER I RECEIVE IT, I ACKNOWLEDGE THAT I DID SO
     VOLUNTARILY AND HAVE KNOWINGLY AND VOLUNTARILY WAIVED MY


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     RIGHT TO CONSIDER THIS AGREEMENT FOR THE FULL 21-DAY PERIOD.


Dated:     21 Dec 01                             By: /s/ Richard W. Barcus
      --------------------                           ---------------------
                                                     RICHARD W. BARCUS


                                                 TELLIUM INC.

Dated:     Jan. 2, 2002                          By: /s/Harry J. Carr
      ----------------------                         ---------------------
                                                     Chairman & CEO





STATE OF NEW JERSEY     )
                        )  ss.:
COUNTY OF __________    )


     On _____________, 2001, before me personally came RICHARD W. BARCUS to me
known and known to me be the individual described in, and who executed, the
foregoing Retirement & Separation Agreement and Release, and duly acknowledged
to me that he executed same.

     Sworn to and subscribed before me
     this ___ day of ________, 2001.


     ----------------------------
     NOTARY PUBLIC

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