Exhibit 10.5

Execution Version

CANADIAN GUARANTEE

CANADIAN GUARANTEE (as amended, modified, restated and/or supplemented from time
to time, this “Guarantee”), dated as of October 28, 2019, made by and among each
of the undersigned guarantors (each, a “Guarantor” and, together with any other
entity that becomes a guarantor hereunder pursuant to Section 23 hereof,
collectively, the “Guarantors”) in favour of Bank of America, N.A., as
administrative agent (together with any successor administrative agent, the
“Administrative Agent”), for the benefit of the Secured Parties (as defined
below). Certain capitalized terms as used herein are defined in Section 1
hereof. Except as otherwise defined herein, all capitalized terms used herein
and defined in the Credit Agreement (as defined below) shall be used herein as
therein defined.

W I T N E S S E T H:

WHEREAS, Ciena Corporation, a Delaware corporation (the “Company”, together with
the Domestic Subsidiaries of the Company that are or become a U.S. Borrower
pursuant to the terms of the Credit Agreement, the “U.S. Borrowers”), Ciena
Canada, Inc., a corporation incorporated under the laws of Canada (together with
the other Canadian Subsidiaries of the Company that are or become a Canadian
Borrower pursuant to the terms of the Credit Agreement, the “Borrowers” and each
a “Borrower”), the lenders from time to time party thereto (the “Lenders”) and
Bank of America, N.A., as administrative agent and collateral agent have entered
into that certain ABL Credit Agreement, dated as of October 28, 2019 (as
amended, modified, restated and/or supplemented from time to time, the “Credit
Agreement”), providing for the making of Loans to the Borrowers and the U.S.
Borrowers as contemplated therein (the Lenders, the Administrative Agent and the
other “Secured Parties” (as defined in the Credit Agreement) are herein called
the “Secured Parties”);

WHEREAS, it is a condition precedent to the making of Loans to the Borrowers and
the U.S. Borrowers under the Credit Agreement that each Guarantor shall have
executed and delivered to the Administrative Agent this Guarantee; and

WHEREAS, each Guarantor will benefit from the incurrence of Loans by the
Borrowers and the U.S. Borrowers and, accordingly, desires to execute this
Guarantee in order to (i) satisfy the condition described in the preceding
paragraph and (ii) induce the Lenders to make Loans to the Borrowers and the
U.S. Borrowers;

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NOW, THEREFORE, in consideration of the foregoing and other benefits accruing to
each Guarantor, the receipt and sufficiency of which are hereby acknowledged,
each Guarantor hereby makes the following representations and warranties to the
Administrative Agent for the benefit of the Secured Parties and hereby covenants
and agrees with each other Guarantor and the Administrative Agent for the
benefit of the Secured Parties as follows:

1. GUARANTEE. (a) Each Guarantor, jointly and severally, irrevocably, absolutely
and unconditionally guarantees as a primary obligor and not merely as surety: to
the Secured Parties the full and prompt payment when due (whether at the stated
maturity, by required prepayment, declaration, acceleration, demand or
otherwise) of (x) all Canadian Obligations and (y) all other obligations
(including, without limitation, obligations which, but for the automatic or any
other stay under applicable Debtor Relief Laws, would become due), liabilities
and indebtedness owing by the Borrowers to the Secured Parties under the Credit
Agreement and each other Loan Document to which any Borrower is a party
(including, without limitation, indemnities, fees and interest thereon
(including, without limitation, in each case any interest, fees or expenses
accruing after the commencement of any bankruptcy, insolvency, receivership,
arrangement, reorganization or similar proceeding at the rate provided for in
the Credit Agreement, whether or not such interest, fees or expenses are an
allowed claim in any such proceeding)), whether now existing or hereafter
incurred under, arising out of or in connection with each such Loan Document
(all such principal, premium, interest, liabilities, indebtedness and
obligations under this clause (a), being herein collectively called the
“Guaranteed Obligations”).

Each Guarantor understands, agrees and confirms that the Secured Parties may
enforce this Guarantee up to the full amount of the Guaranteed Obligations
against such Guarantor without proceeding against any other Guarantor or any
Borrower, or against any security for the Guaranteed Obligations, or under any
other guarantee covering all or a portion of the Guaranteed Obligations. This
Guarantee is a guarantee of prompt payment and performance and not of
collection. For purposes of this Guarantee, the term “Guarantor” as applied to
any Borrower or any other Guarantor shall refer to such Borrower or such other
Guarantor as a guarantor of indebtedness incurred by another Borrower, and not
indebtedness directly incurred by such Guarantor, in its capacity as Borrower or
otherwise.

The following capitalized terms used herein shall have the definitions specified
below:

“Guarantee Supplement” shall mean a guarantee supplement, in a form reasonably
satisfactory to the Administrative Agent and attached hereto as Exhibit A,
signed and delivered to the Administrative Agent for the purpose of adding a
Subsidiary as a party hereto pursuant to Section 23.

“Termination Date” shall mean the date upon which Payment in Full occurs.

(b) Additionally, each Guarantor, jointly and severally, unconditionally,
absolutely and irrevocably, guarantees the payment of any and all Guaranteed
Obligations whether or not due and payable by any Borrower upon the occurrence,
in respect of any Borrower, of any of the events specified in Section 8.01(f) of
the Credit Agreement, and unconditionally, absolutely and irrevocably, jointly
and severally, promises to pay such Guaranteed Obligations to the Secured
Parties, or order, on demand.

2. LIABILITY OF GUARANTORS ABSOLUTE. The liability of each Guarantor hereunder
is primary, absolute, joint and several, and unconditional and is exclusive and
independent of any security for or other guarantee of the indebtedness of any
Borrower whether executed by such Guarantor, any other Guarantor, any other
guarantor or by any other party, and the liability of each Guarantor hereunder
shall not be affected or impaired by any circumstance or occurrence whatsoever,
including, without limitation: (a) any direction as to application of

 

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payment by any Borrower or any other party, (b) any other continuing or other
guarantee, undertaking or maximum liability of a Guarantor or of any other party
as to the Guaranteed Obligations, (c) any payment on or in reduction of any such
other guarantee or undertaking, (d) any dissolution, termination or increase,
decrease or change in personnel by any Borrower, (e) the failure of a Guarantor
to receive any benefit from or as a result of its execution, delivery and
performance of this Guarantee, (f) any payment made to any Secured Party on the
indebtedness which any Secured Party repays any Borrower pursuant to court order
in any bankruptcy, reorganization, arrangement, moratorium or other debtor
relief proceeding, and each Guarantor waives any right to the deferral or
modification of its obligations hereunder by reason of any such proceeding,
(g) any action or inaction by the Secured Parties as contemplated in Section 5
hereof or (h) any invalidity, rescission, irregularity or unenforceability of
all or any part of the Guaranteed Obligations or of any security therefor.

3. OBLIGATIONS OF GUARANTORS INDEPENDENT. The obligations of each Guarantor
hereunder are independent of the obligations of any other Guarantor, any other
guarantor or any Borrower, and a separate action or actions may be brought and
prosecuted against each Guarantor whether or not action is brought against any
other Guarantor, any other guarantor or any Borrower and whether or not any
other Guarantor, any other guarantor or any Borrower is joined in any such
action or actions. Each Guarantor waives (to the fullest extent permitted by
applicable law) the benefits of any statute of limitations affecting its
liability hereunder or the enforcement thereof. Any payment by any Borrower or
other circumstance which operates to toll any statute of limitations as to any
Borrower shall operate to toll the statute of limitations as to each Guarantor.

4. WAIVERS BY GUARANTORS. (a) Each Guarantor hereby waives (to the fullest
extent permitted by applicable law) notice of acceptance of this Guarantee and
notice of the existence, creation or incurrence of any new or additional
liability to which it may apply, and waives promptness, diligence, presentment,
demand of payment, demand for performance, protest, notice of dishonor or
nonpayment of any such liabilities, suit or taking of other action by the
Administrative Agent or any other Secured Party against, and any other notice
to, any party liable thereon (including such Guarantor, any other Guarantor, any
other guarantor or any Borrower) and each Guarantor further hereby waives any
and all notice of the creation, renewal, extension or accrual of any of the
Guaranteed Obligations and notice or proof of reliance by any Secured Party upon
this Guarantee, and the Guaranteed Obligations shall conclusively be deemed to
have been created, contracted or incurred, or renewed, extended, amended,
modified, supplemented or waived, in reliance upon this Guarantee.

(b) Each Guarantor waives any right (except as shall be required by applicable
statute and cannot be waived) to require the Secured Parties to: (i) proceed
against any Borrower, any other Guarantor, any other guarantor of the Guaranteed
Obligations or any other party; (ii) proceed against or exhaust any security
held from any Borrower, any other Guarantor, any other guarantor of the
Guaranteed Obligations or any other party; or (iii) pursue any other remedy in
the Secured Parties’ power whatsoever. Each Guarantor waives any defense based
on or arising out of any defense of any Borrower, any other Guarantor, any other
guarantor of the Guaranteed Obligations or any other party other than the
occurrence of the Termination Date, including, without limitation, any defense
based on or arising out of the disability of any Borrower, any other Guarantor,
any other guarantor of the Guaranteed Obligations or any other

 

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party, or the unenforceability of the Guaranteed Obligations or any part thereof
from any cause, or the cessation from any cause of the liability of any Borrower
other than the occurrence of the Termination Date. The Secured Parties may, at
their election, upon the occurrence and during the continuance of an Event of
Default, foreclose on any collateral serving as security held by the
Administrative Agent or the other Secured Parties by one or more judicial or
nonjudicial sales, whether or not every aspect of any such sale is commercially
reasonable (to the extent such sale is permitted by applicable law), or exercise
any other right or remedy the Secured Parties may have against any Borrower, or
any other party, or any security, without affecting or impairing in any way the
liability of any Guarantor hereunder except to the extent the Termination Date
has occurred. Each Guarantor waives any defense arising out of any such election
by the Secured Parties, even though such election may operate to impair or
extinguish any right of reimbursement, contribution, indemnification or
subrogation or other right or remedy of such Guarantor against any Borrower, any
other guarantor of the Guaranteed Obligations or any other party or any
security.

(c) Each Guarantor has knowledge and assumes all responsibility for being and
keeping itself informed of each Borrower’s and each other Guarantor’s financial
condition, affairs and assets, and of all other circumstances bearing upon the
risk of nonpayment of the Guaranteed Obligations and the nature, scope and
extent of the risks which such Guarantor assumes and incurs hereunder, and has
adequate means to obtain from each Borrower and each other Guarantor on an
ongoing basis information relating thereto and each Borrower’s and each other
Guarantor’s ability to pay and perform its respective Guaranteed Obligations,
and agrees to assume the responsibility to keep so informed for so long as such
Guarantor is a party to this Guarantee. Each Guarantor acknowledges and agrees
that (x) the Secured Parties shall have no obligation to investigate the
financial condition or affairs of any Borrower or any other Guarantor for the
benefit of such Guarantor nor to advise such Guarantor of any fact respecting,
or any change in, the financial condition, assets or affairs of any Borrower or
any other Guarantor that might become known to any Secured Party at any time,
whether or not such Secured Party knows or believes or has reason to know or
believe that any such fact or change is unknown to such Guarantor, or might (or
does) increase the risk of such Guarantor as guarantor hereunder, or might (or
would) affect the willingness of such Guarantor to continue as a Guarantor
hereunder and (y) the Secured Parties shall have no duty to advise any Guarantor
of information known to them regarding any of the aforementioned circumstances
or risks.

(d) Each Guarantor hereby acknowledges and agrees that no Secured Party nor any
other Person shall be under any obligation (a) to marshal any assets in favour
of such Guarantor or in payment of any or all of the liabilities of any Borrower
under the Loan Documents or the obligation of such Guarantor hereunder or (b) to
pursue any other remedy that such Guarantor may or may not be able to pursue
itself any right to which such Guarantor hereby waives.

(e) Each Guarantor warrants and agrees that each of the waivers set forth in
Section 3 hereof and in this Section 4 is made with full knowledge of its
significance and consequences and that if any of such waivers are determined to
be contrary to any applicable law or public policy, such waivers shall be
effective only to the maximum extent permitted by applicable law.

 

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5. RIGHTS OF SECURED PARTIES. Any Secured Party may (except as shall be required
by applicable statute and cannot be waived) at any time and from time to time
without the consent of, or notice to, any Guarantor, without incurring
responsibility to such Guarantor, without impairing or releasing the obligations
or liabilities of such Guarantor hereunder, upon or without any terms or
conditions and in whole or in part:

(a) change the manner, place or terms of payment of, and/or change, increase or
extend the time of payment of, renew, increase, accelerate or alter, any of the
Guaranteed Obligations (including, without limitation, any increase or decrease
in the rate of interest thereon or the principal amount thereof), any security
therefor, or any liability incurred directly or indirectly in respect thereof,
and the guarantee herein made shall apply to the Guaranteed Obligations as so
changed, extended, increased, accelerated, renewed or altered;

(b) take and hold security for the payment of the Guaranteed Obligations and
sell, exchange, release, surrender, impair, realize upon or otherwise deal with
in any manner and in any order any property or other collateral by whomsoever at
any time pledged or mortgaged to secure, or howsoever securing, the Guaranteed
Obligations or any liabilities (including any of those hereunder) incurred
directly or indirectly in respect thereof or hereof, and/or any offset
thereagainst;

(c) exercise or refrain from exercising any rights against any Borrower, any
other Loan Party, any Subsidiary thereof, any other guarantor of any Borrower or
others or otherwise act or refrain from acting;

(d) release or substitute any one or more endorsers, Guarantors, other
guarantors, any Borrower or other obligors;

(e) settle or compromise any of the Guaranteed Obligations, any security
therefor or any liability (including any of those hereunder) incurred directly
or indirectly in respect thereof or hereof, and may subordinate the payment of
all or any part thereof to the payment of any liability (whether due or not) of
any Borrower to creditors of any Borrower other than the Secured Parties;

(f) apply any sums by whomsoever paid or howsoever realized to any liability or
liabilities of any Borrower to the Secured Parties regardless of what
liabilities of such Borrower remain unpaid;

(g) consent to or waive any breach of, or any act, omission or default under,
any of the Loan Documents or any of the instruments or agreements referred to
therein, or otherwise amend, modify or supplement any of the Loan Documents or
any of such other instruments or agreements;

(h) act or fail to act in any manner which may deprive such Guarantor of its
right to subrogation against any Borrower to recover full indemnity for any
payments made pursuant to this Guarantee; and/or

 

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(i) take any other action or omit to take any other action which would, under
otherwise applicable principles of common law, give rise to a legal or equitable
discharge of such Guarantor from its liabilities under this Guarantee
(including, without limitation, any action or omission whatsoever that might
otherwise vary the risk of such Guarantor or constitute a legal or equitable
defense to or discharge of the liabilities of a guarantor or surety or that
might otherwise limit recourse against such Guarantor).

No invalidity, illegality, irregularity or unenforceability of all or any part
of the Guaranteed Obligations, the Loan Documents or any other agreement or
instrument relating to the Guaranteed Obligations or of any security or
guarantee therefor shall affect, impair or be a defense to this Guarantee, and
this Guarantee shall be primary, absolute and unconditional notwithstanding the
occurrence of any event or the existence of any other circumstances which might
constitute a legal or equitable discharge of a surety or guarantor except the
occurrence of the Termination Date.

6. CONTINUING GUARANTEE. This Guarantee is a continuing one and all liabilities
to which it applies or may apply under the terms hereof shall be conclusively
presumed to have been created in reliance hereon. No failure or delay on the
part of any Secured Party in exercising any right, power or privilege hereunder
shall operate as a waiver thereof, nor shall any single or partial exercise of
any right, power or privilege hereunder preclude any other or further exercise
thereof or the exercise of any other right, power or privilege. The rights and
remedies herein expressly specified are cumulative and not exclusive of any
rights or remedies which any Secured Party would otherwise have. No notice to or
demand on any Guarantor in any case shall entitle such Guarantor to any other
further notice or demand in similar or other circumstances or constitute a
waiver of the rights of any Secured Party to any other or further action in any
circumstances without notice or demand. It is not necessary for any Secured
Party to inquire into the capacity or powers of any Borrower or the officers,
directors, partners or agents acting or purporting to act on its behalf, and any
indebtedness made or created in reliance upon the professed exercise of such
powers shall be guaranteed hereunder.

7. SUBORDINATION OF INDEBTEDNESS HELD BY GUARANTORS. Any indebtedness of any
Borrower now or hereafter held by any Guarantor is hereby subordinated to the
Guaranteed Obligations of such Borrower to the Secured Parties; and the
indebtedness of such Borrower to any Guarantor, if the Administrative Agent,
after an Event of Default has occurred and is continuing, so requests, shall be
collected, enforced and received by such Guarantor as trustee for the Secured
Parties and be paid over to the Secured Parties on account of the Guaranteed
Obligations of such Borrower to the Secured Parties, but without affecting or
impairing in any manner the liability of such Guarantor under the other
provisions of this Guarantee. Without limiting the generality of the foregoing,
each Guarantor hereby agrees with the Secured Parties that it will not exercise
any right of subrogation which it may at any time otherwise have as a result of
this Guarantee (whether contractual or under any applicable Debtor Relief Law,
or otherwise) until the Termination Date; provided, that if any amount shall be
paid to such Guarantor on account of such subrogation rights at any time prior
to the Termination Date, such amount shall be held in trust for the benefit of
the Secured Parties and shall promptly be paid to the Secured Parties to be
credited and applied upon the Guaranteed Obligations, whether matured or
unmatured, in accordance with the terms of the Loan Documents or, if the Loan
Documents do not provide for the application of such amount, to be held by the
Secured Parties as collateral security for any Guaranteed Obligations thereafter
existing.

 

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8. GUARANTEE ENFORCEABLE BY THE ADMINISTRATIVE AGENT. Notwithstanding anything
to the contrary contained elsewhere in this Guarantee, the Secured Parties agree
(by their acceptance of the benefits of this Guarantee) that this Guarantee may
be enforced only by the action of the Administrative Agent, acting upon the
instructions of the Required Lenders and that no other Secured Party shall have
any right individually to seek to enforce or to enforce this Guarantee or to
realize upon the security to be granted by the Collateral Documents, it being
understood and agreed that such rights and remedies may be exercised by the
Administrative Agent, for the benefit of the Secured Parties upon the terms of
this Guarantee and the Collateral Documents. The Secured Parties further agree
that this Guarantee may not be enforced against any director, officer, employee,
partner, member or stockholder of any Guarantor (except to the extent such
partner, member or stockholder is also a Guarantor hereunder). It is understood
and agreed that the agreement in this Section 8 is among and solely for the
benefit of the Secured Parties and that, if the Required Lenders so agree
(without requiring the consent of any Guarantor), this Guarantee may be directly
enforced by any Secured Party.

9. REPRESENTATIONS, WARRANTIES AND COVENANTS OF GUARANTORS. In order to induce
the Lenders to make Loans to the Borrowers pursuant to the Credit Agreement each
Guarantor represents, warrants and covenants that:

(a) such Guarantor (i) is duly organized or formed, validly existing and, as
applicable, in good standing under the Laws of the jurisdiction of its
incorporation or organization (to the extent such concept is applicable in the
relevant jurisdiction), (ii) has all requisite power and authority and all
requisite governmental licenses, authorizations, consents and approvals to
(A) own or lease its assets and carry on its business and (B) execute, deliver
and perform its obligations hereunder, and (iii) is duly qualified and is
licensed and, as applicable, in good standing (to the extent such concept is
applicable in the relevant jurisdiction) under the Laws of each jurisdiction
where its ownership, lease or operation of properties or the conduct of its
business requires such qualification or license; except in each case referred to
in clause (ii)(A) or (iii), to the extent that failure to do so could not
reasonably be expected to have a Material Adverse Effect;

(b) the execution, delivery and performance by such Guarantor of each Loan
Document to which such Guarantor is a party has been duly authorized by all
necessary corporate or other organizational action, and do not and will not
(i) contravene the terms of any of such Guarantor’s Organization Documents;
(ii) conflict with or result in any breach or contravention of, or the creation
of any Lien (other than Liens created under the Loan Documents) under, or
require any payment to be made under (A) any material Contractual Obligation to
which such Guarantor is a party or affecting such Guarantor or the properties of
such Guarantor or any of its Subsidiaries or (B) any order, injunction, writ or
decree of any Governmental Authority or any arbitral award to which such
Guarantor or its property is subject; or (iii) violate any Law;

 

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(c) such Guarantor has duly executed and delivered each of the Loan Documents
that it is party thereto. This Agreement constitutes, and each other Loan
Document when so delivered will constitute, a legal, valid and binding
obligation of such Guarantor, enforceable against such Guarantor that is party
thereto in accordance with its terms, subject to applicable bankruptcy,
insolvency, reorganization, moratorium or other laws affecting creditors’ rights
generally and subject to general principles of equity, regardless of whether
considered in a proceeding in equity or at law;

(d) no approval, consent, exemption, authorization, or other action by, or
notice to, or filing with, any Governmental Authority or any other Person is
necessary or required in connection with (i) the execution, delivery or
performance by such Guarantor of this Agreement or any other Loan Document, or
for the consummation of the Transaction, (ii) the grant by such Guarantor of the
Liens granted by it pursuant to the Collateral Documents, or (iii) the
perfection or maintenance of the Liens created under the Collateral Documents
(including, subject to the Intercreditor Agreement, the first priority nature
thereof) other than (A) those that have already been obtained and are now in
full force and effect, (B) filings to perfect the Liens created by the
Collateral Documents, and (C) those actions as contemplated by Section 2.1 of
the Canadian Security Agreement;

(e) there are no actions, suits, proceedings, investigations, claims or disputes
pending or, to the knowledge of any Responsible Officer of such Guarantor,
threatened or contemplated in writing, at law, in equity, in arbitration or
before any Governmental Authority, by or against such Guarantor or against any
of its properties or revenues that (i) purport to affect or pertain to this
Agreement, any other Loan Document or the consummation of the Transaction, or
(ii) either individually or in the aggregate could reasonably be expected to
have a Material Adverse Effect; and

(f) until the Termination Date, such Guarantor will comply, and will cause each
of its Subsidiaries to comply, with all of the applicable provisions, covenants
and agreements contained in Articles 6 and 7 of the Credit Agreement which are
expressly applicable to such Guarantor and/or such Guarantor’s Subsidiaries, and
will take, or will refrain from taking, as the case may be, all actions that are
necessary to be taken or not taken so that no violation of any provision,
covenant or agreement contained in Articles 6 and 7 of the Credit Agreement
which are expressly applicable to such Guarantor and/or such Guarantor’s
Subsidiaries, and so that no Default or Event of Default, is caused by the
actions of such Guarantor or any of its Subsidiaries.

10. EXPENSES. The Guarantors hereby jointly and severally agree to pay (i) all
reasonable and documented out-of-pocket expenses incurred by the Administrative
Agent and its Affiliates (including the reasonable fees, charges and
disbursements of counsel for the Administrative Agent), in connection with any
amendment, waiver or consent relating hereto and (ii) all reasonable and
documented out-of-pocket expenses incurred by the Administrative Agent or any
Secured Party (including the reasonable fees, charges and disbursements of
(x) one counsel to the Administrative Agent (plus one local counsel in each
applicable jurisdiction and one specialty counsel in each applicable specialty),
(y) one counsel to the Secured Parties (plus one local counsel in each
applicable jurisdiction and one specialty counsel in each applicable

 

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specialty) and (z) in the case of an actual conflict of interest, one additional
counsel for each group of similarly situated affected persons, taken as a
whole), in connection with the enforcement or protection of its rights in
connection with this Guarantee and the other Loan Documents, including its
rights under this Section.

11. BENEFIT AND BINDING EFFECT. This Guarantee shall be binding upon each
Guarantor and its successors and assigns and shall inure to the benefit of the
Secured Parties and their successors and assigns.

12. AMENDMENTS; WAIVERS. Neither this Guarantee nor any provision hereof may be
changed, waived, discharged or terminated except with the written consent of
each Guarantor directly affected thereby (it being understood that the addition
or release of any Guarantor hereunder shall not constitute a change, waiver,
discharge or termination affecting any Guarantor other than the Guarantor so
added or released) and with the written consent of the Required Lenders (or, to
the extent required by Section 10.01 of the Credit Agreement, with the written
consent of each Lender) at all times prior to the Termination Date.

13. SET OFF. In addition to any rights now or hereafter granted under applicable
law (including, without limitation, applicable Debtor Relief Laws) and not by
way of limitation of any such rights, upon the occurrence and during the
continuance of an Event of Default, each Secured Party and each of their
respective Affiliates is hereby authorized, at any time or from time to time,
without notice to any Guarantor or to any other Person, any such notice being
expressly waived, to set off and to appropriate and apply any and all deposits
(general or special) and any other indebtedness at any time held or owing by
such Secured Party to or for the credit or the account of such Guarantor,
against and on account of the obligations and liabilities of such Guarantor to
such Secured Party under this Guarantee, irrespective of whether or not such
Secured Party shall have made any demand hereunder and although said
obligations, liabilities, deposits or claims, or any of them, shall be
contingent or unmatured.

14. NOTICE. Except as otherwise specified herein, all notices, requests, demands
or other communications to or upon the respective parties hereto shall be sent
or delivered by mail, telecopy or courier service and all such notices and
communications shall, when mailed, telecopied or sent by courier, be effective
when deposited in the mail, delivered to the overnight courier or sent by
telecopier, except that notices and communications to the Administrative Agent
or any Guarantor shall not be effective until received by the Administrative
Agent or such Guarantor, as the case may be. All notices and other
communications shall be in writing and addressed to such party at (i) in the
case of any Secured Party, as provided in the Credit Agreement and (ii) in the
case of any Guarantor, at its address set forth opposite its signature page
below; or in any case at such other address as any of the Persons listed above
may hereafter notify the others in writing.

15. REINSTATEMENT. Notwithstanding anything to the contrary contained herein, if
any claim is ever made upon any Secured Party for repayment or recovery of any
amount or amounts received in payment or on account of any of the Guaranteed
Obligations and any of the aforesaid payees repays all or part of said amount by
reason of (i) any judgment, decree or order of any court or administrative body
having jurisdiction over such payee or any of its property or (ii) any
settlement or compromise of any such claim effected by such payee with

 

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any such claimant (including, without limitation, any Borrower), then and in
such event each Guarantor agrees that any such judgment, decree, order,
settlement or compromise shall be binding upon such Guarantor, notwithstanding
any revocation hereof or the cancellation of any Note, any other Loan Document
or any other instrument evidencing any liability of any Borrower, and such
Guarantor shall be and remain liable to the aforesaid payees hereunder for the
amount so repaid or recovered to the same extent as if such amount had never
originally been received by any such payee.

16. CONSENT TO JURISDICTION; SERVICE OF PROCESS; AND WAIVER OF TRIAL BY JURY.
(a) THIS GUARANTEE AND ANY CLAIMS, CONTROVERSY, DISPUTE OR CAUSE OF ACTION
(WHETHER IN CONTRACT OR TORT OR OTHERWISE) BASED UPON, ARISING OUT OF OR
RELATING TO THIS GUARANTEE AND THE TRANSACTIONS CONTEMPLATED HEREBY SHALL BE
GOVERNED BY, AND CONSTRUED IN ACCORDANCE WITH, THE LAW OF THE PROVINCE OF
ONTARIO AND THE FEDERAL LAWS OF CANADA APPLICABLE THEREIN. EACH GUARANTOR
IRREVOCABLY AND UNCONDITIONALLY AGREES THAT IT WILL NOT COMMENCE ANY ACTION,
LITIGATION OR PROCEEDING OF ANY KIND OR DESCRIPTION, WHETHER IN LAW OR EQUITY,
WHETHER IN CONTRACT OR IN TORT OR OTHERWISE, AGAINST ANY SECURED PARTY, OR ANY
RELATED PARTY THEREOF IN ANY WAY RELATING TO THIS GUARANTEE OR THE TRANSACTIONS
RELATING HERETO, IN ANY FORUM OTHER THAN THE COURTS OF THE PROVINCE OF ONTARIO
SITTING IN TORONTO, AND ANY APPELLATE COURT THEREFROM, AND EACH OF THE PARTIES
HERETO IRREVOCABLY AND UNCONDITIONALLY SUBMITS TO THE JURISDICTION OF SUCH
COURTS AND AGREES THAT ALL CLAIMS IN RESPECT OF ANY SUCH ACTION, LITIGATION OR
PROCEEDING MAY BE HEARD AND DETERMINED IN SUCH ONTARIO COURT. EACH OF GUARANTORS
HEREBY AGREES THAT A FINAL JUDGMENT IN ANY SUCH ACTION, LITIGATION OR PROCEEDING
SHALL BE CONCLUSIVE AND MAY BE ENFORCED IN OTHER JURISDICTIONS BY SUIT ON THE
JUDGMENT OR IN ANY OTHER MANNER PROVIDED BY LAW. NOTHING IN THIS GUARANTEE OR IN
ANY OTHER LOAN DOCUMENT SHALL AFFECT ANY RIGHT THAT ANY SECURED PARTY MAY
OTHERWISE HAVE TO BRING ANY ACTION OR PROCEEDING RELATING TO THIS GUARANTEE OR
ANY OTHER LOAN DOCUMENT AGAINST EACH GUARANTOR OR ITS PROPERTIES IN THE COURTS
OF ANY JURISDICTION. EACH GUARANTOR IRREVOCABLY AND UNCONDITIONALLY WAIVES, TO
THE FULLEST EXTENT PERMITTED BY APPLICABLE LAW, ANY OBJECTION THAT IT MAY NOW OR
HEREAFTER HAVE TO THE LAYING OF VENUE OF ANY ACTION OR PROCEEDING ARISING OUT OF
OR RELATING TO THIS GUARANTEE OR ANY OTHER LOAN DOCUMENT IN ANY COURT REFERRED
TO IN SUBSECTION (a) OF THIS SECTION. EACH OF THE GUARANTORS HEREBY IRREVOCABLY
WAIVES, TO THE FULLEST EXTENT PERMITTED BY APPLICABLE LAW, THE DEFENSE OF AN
INCONVENIENT FORUM TO THE MAINTENANCE OF SUCH ACTION OR PROCEEDING IN ANY SUCH
COURT.

 

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(b) EACH GUARANTOR HEREBY IRREVOCABLY CONSENTS TO SERVICE OF PROCESS IN THE
MANNER PROVIDED FOR NOTICES IN SECTION 14. NOTHING IN THIS GUARANTEE WILL AFFECT
THE RIGHT OF ANY GUARANTOR TO SERVE PROCESS IN ANY OTHER MANNER PERMITTED BY
APPLICABLE LAW.

(c) EACH GUARANTOR HEREBY IRREVOCABLY WAIVES, TO THE FULLEST EXTENT PERMITTED BY
APPLICABLE LAW, ANY RIGHT IT MAY HAVE TO A TRIAL BY JURY IN ANY LEGAL PROCEEDING
DIRECTLY OR INDIRECTLY ARISING OUT OF OR RELATING TO THIS GUARANTEE OR ANY OTHER
LOAN DOCUMENT OR THE TRANSACTIONS CONTEMPLATED HEREBY OR THEREBY (WHETHER BASED
ON CONTRACT, TORT OR ANY OTHER THEORY). EACH GUARANTOR (A) CERTIFIES THAT NO
REPRESENTATIVE, AGENT OR ATTORNEY OF ANY OTHER PERSON HAS REPRESENTED, EXPRESSLY
OR OTHERWISE, THAT SUCH OTHER PERSON WOULD NOT, IN THE EVENT OF LITIGATION, SEEK
TO ENFORCE THE FOREGOING WAIVER AND (B) ACKNOWLEDGES THAT IT AND THE OTHER
PARTIES HERETO HAVE BEEN INDUCED TO ENTER INTO THIS GUARANTEE AND THE OTHER LOAN
DOCUMENTS BY, AMONG OTHER THINGS, THE MUTUAL WAIVERS AND CERTIFICATIONS IN THIS
SECTION.

17. RELEASE OF LIABILITY OF GUARANTOR. In the event that a Guarantor becomes an
Immaterial Subsidiary or all of the Equity Interests of one or more Guarantors
(other than the Company) is sold or otherwise disposed of or liquidated in
compliance with the requirements of Section 7.04 or 7.05 of the Credit Agreement
(or such sale, other disposition or liquidation has been approved in writing by
the Required Lenders (or all the Lenders if required by Section 10.01 of the
Credit Agreement)) and the proceeds of such sale, disposition or liquidation
will be applied in accordance with the provisions of the Credit Agreement, to
the extent applicable, such Immaterial Subsidiary, or such Guarantor, as
applicable, shall, or upon consummation of such sale or other disposition
(except to the extent that such sale or disposition is to the Company or another
Subsidiary thereof), as applicable, shall be released from this Guarantee
automatically and without further action and this Guarantee shall, as to each
such Guarantor or Guarantors, terminate, and have no further force or effect (it
being understood and agreed that the sale of one or more Persons that own,
directly or indirectly, all of the Equity Interests of any Guarantor shall be
deemed to be a sale of such Guarantor for the purposes of this Section 17).
Subject to Section 15, on the Termination Date this Guarantee shall terminate
(provided that all indemnities set forth herein shall survive such termination)
and each Guarantor shall be released from its obligations under this Guarantee.

18. CONTRIBUTION. At any time a payment in respect of the Guaranteed Obligations
is made under this Guarantee, the right of contribution of each Guarantor
against each other Guarantor shall be determined as provided in the immediately
following sentence, with the right of contribution of each Guarantor to be
revised and restated as of each date on which a payment (a “Relevant Payment”)
is made on the Guaranteed Obligations under this Guarantee. At any time that a
Relevant Payment is made by a Guarantor that results in the aggregate payments
made by such Guarantor in respect of the Guaranteed Obligations to and including
the date of the Relevant Payment exceeding such Guarantor’s Contribution
Percentage (as defined below) of the aggregate payments made by all Guarantors
in respect of the Guaranteed Obligations to and including the date of the
Relevant Payment (such excess, the “Aggregate Excess Amount”), each such
Guarantor shall have a right of contribution against each other Guarantor who
has made payments in respect of the Guaranteed Obligations to and

 

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including the date of the Relevant Payment in an aggregate amount less than such
other Guarantor’s Contribution Percentage of the aggregate payments made to and
including the date of the Relevant Payment by all Guarantors in respect of the
Guaranteed Obligations (the aggregate amount of such deficit, the “Aggregate
Deficit Amount”) in an amount equal to (x) a fraction the numerator of which is
the Aggregate Excess Amount of such Guarantor and the denominator of which is
the Aggregate Excess Amount of all Guarantors multiplied by (y) the Aggregate
Deficit Amount of such other Guarantor. A Guarantor’s right of contribution
pursuant to the preceding sentences shall arise at the time of each computation,
subject to adjustment to the time of each computation; provided that no
Guarantor may take any action to enforce such right until the Termination Date,
it being expressly recognized and agreed by all parties hereto that any
Guarantor’s right of contribution arising pursuant to this Section 18 against
any other Guarantor shall be expressly junior and subordinate to such other
Guarantor’s obligations and liabilities in respect of the Guaranteed Obligations
and any other obligations owing under this Guarantee. As used in this
Section 18: (i) each Guarantor’s “Contribution Percentage” shall mean the
percentage obtained by dividing (x) the Adjusted Net Worth (as defined below) of
such Guarantor by (y) the aggregate Adjusted Net Worth of all Guarantors;
(ii) the “Adjusted Net Worth” of each Guarantor shall mean the greater of
(x) the Net Worth (as defined below) of such Guarantor and (y) zero; and
(iii) the “Net Worth” of each Guarantor shall mean the amount by which the fair
saleable value of such Guarantor’s assets on the date of any Relevant Payment
exceeds its existing debts and other liabilities (including contingent
liabilities, but without giving effect to any Guaranteed Obligations arising
under this Guarantee or any guaranteed obligations arising under any guarantee
of any Permitted Additional Indebtedness) on such date. Notwithstanding anything
to the contrary contained above, any Guarantor that is released from this
Guarantee pursuant to Section 17 hereof shall thereafter have no contribution
obligations, or rights, pursuant to this Section 18, and at the time of any such
release, if the released Guarantor had an Aggregate Excess Amount or an
Aggregate Deficit Amount, same shall be deemed reduced to $0, and the
contribution rights and obligations of the remaining Guarantors shall be
recalculated on the respective date of release (as otherwise provided above)
based on the payments made hereunder by the remaining Guarantors. All parties
hereto recognize and agree that, except for any right of contribution arising
pursuant to this Section 18, each Guarantor who makes any payment in respect of
the Guaranteed Obligations shall have no right of contribution or subrogation
against any other Guarantor in respect of such payment until the Termination
Date. Each of the Guarantors recognizes and acknowledges that the rights to
contribution arising hereunder shall constitute an asset in favour of the party
entitled to such contribution. In this connection, each Guarantor has the right
to waive its contribution right against any Guarantor to the extent that after
giving effect to such waiver such Guarantor would remain solvent, in the
determination of the Required Lenders.

19. LIMITATION ON GUARANTEED OBLIGATIONS. Each Guarantor and each Secured Party
(by its acceptance of the benefits of this Guarantee) hereby confirms that it is
its intention that this Guarantee not constitute a transfer at undervalue or
fraudulent transfer or conveyance for purposes of any applicable Debtor Relief
Law. To effectuate the foregoing intention, each Guarantor and each Secured
Party (by its acceptance of the benefits of this Guarantee) hereby irrevocably
agrees that the Guaranteed Obligations guaranteed by such Guarantor shall be
limited to such amount as will, after giving effect to such maximum amount and
all other (contingent or otherwise) liabilities of such Guarantor that are
relevant under such laws and after giving effect to any rights to contribution
pursuant to any agreement providing for an equitable contribution among such
Guarantor and the other Guarantors, result in the Guaranteed Obligations of such
Guarantor in respect of such maximum amount not constituting a fraudulent
transfer or conveyance.

 

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20. COUNTERPARTS. This Guarantee may be executed in any number of counterparts
and by the different parties hereto on separate counterparts, each of which when
so executed and delivered shall be an original, but all of which shall together
constitute one and the same instrument. A set of counterparts executed by all
the parties hereto shall be lodged with the Company and the Administrative
Agent.

21. PAYMENTS. All payments made by any Guarantor hereunder will be made without
setoff, counterclaim or other defense and on the same basis as payments are made
by the applicable Borrowers under the Credit Agreement.

22. JUDGMENT CURRENCY.

The parties hereto agree that the terms of Section 1.11 of the Credit Agreement
are incorporated herein by reference, mutatis mutandis.

23. ADDITIONAL GUARANTORS. It is understood and agreed that any Wholly-Owned
Domestic Subsidiary of the Company that is required to execute a counterpart of
this Guarantee after the date hereof pursuant to the Credit Agreement shall
become a Guarantor hereunder by (x) executing and delivering a counterpart
hereof, a Joinder Agreement or a Guarantee Supplement in the form attached
hereto as Exhibit A, and delivering the same to the Administrative Agent
(provided such Guarantee Supplement shall not require the consent of any
Guarantor) and (y) taking all actions as specified in this Guarantee as would
have been taken by such Guarantor had it been an original party to this
Guarantee, in each case with all documents required above to be delivered to the
Administrative Agent and actions required to be taken above to be taken to the
reasonable satisfaction of the Administrative Agent.

24. HEADINGS DESCRIPTIVE. The headings of the several Sections of this Guarantee
are inserted for convenience only and shall not in any way affect the meaning or
construction of any provision of this Guarantee.

* * *

 

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IN WITNESS WHEREOF, each Guarantor has caused this Canadian Guarantee to be
executed and delivered as of the date first above written.

 

        

GUARANTORS:

7035 Ridge Road

Hanover, Maryland 21076

Attention: Treasurer’s Office

Facsimile:

   

CIENA CANADA, INC.

    By:  

/s/ Jiong Liu

with a copy to:       Name: Jiong Liu

 

7035 Ridge Road

Hanover, Maryland 21076

Attention: General Counsel’s Office

Facsimile:

      Title: Jiong Liu

 

[Signature Page to Canadian Guarantee]

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

Accepted and Agreed to:

BANK OF AMERICA, N.A.,

as Administrative Agent

By:  

/s/ John M. Olsen

  Name: John M. Olsen   Title: John M. Olsen

 

[Signature Page to Canadian Guarantee]