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                                                                   EXHIBIT 10.19

                      REDBACK NETWORKS INC. 2001 NON PLAN

                          NOTICE OF STOCK OPTION GRANT

     Kevin DeNuccio ("Optionee") has been granted the following option to
purchase Common Stock of Redback Networks Inc. (the "Company"):

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     Total Number of Shares Granted:     6,500,000

     Type of Option:                     Nonstatutory Stock Option

     Exercise Price Per Share:           $ 4.17

     Date of Grant:                      August 29, 2001

     Date Exercisable:                   This option may be exercised, in whole or in part, for
                                         1,625,000 of the Shares subject to this option at any
                                         time after the Date of Grant.

     Vesting Commencement Date:          August 29, 2001

     Vesting Schedule:                   The Pro Rata Return Portion of the 1,625,000 shares will be
                                         subject to the Right of Repurchase by the company at the
                                         exercise price if, before you complete 12 months continuous
                                         employment with the Company, your employment ends due to the
                                         occurance of a Pay-back event (as defined in your employment
                                         agreement).

                                         This option becomes exercisable with respect to the remaining
                                         4,875,000 of the Shares subject to this option in equal monthly
                                         installments of 2.777% over your first 36 months of continuous
                                         employment from the Vesting Commencement Date. If you are subject to
                                         an Involuntary Termination, then the exercisable portion of the
                                         remaining 4,875,000 shares will be determined by adding 12 months to
                                         the actual period of employment that you have completed with the
                                         Company.

     Expiration Date:                    August 29, 2011

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In the event a Change in Control occurs (as defined in the attached Stock Option
Agreement) before your employment terminates then your stock option granted
hereunder will immediately be fully vested and exercisable with respect to all
shares and the Company's right to repurchase shares hereunder will lapse in
full.

By your signature and the signature of the Company's representative below, you
and the Company agree that this option is granted under and governed by the
terms and conditions of the attached Stock Option Agreement, which is attached
to and made a part of this document.

OPTIONEE:                               REDBACK NETWORKS INC.

/s/ Kevin A. DeNuccio                   By: /s/ Dennis P. Wolf
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                      REDBACK NETWORKS INC. 2001 NON-PLAN

                             STOCK OPTION AGREEMENT
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Tax Treatment                This option is intended to be a nonstatutory option, as provided in the Notice of
                             Stock Option Grant.

Vesting                      This option becomes exercisable in installments, as shown in the
                             Notice of Stock Option Grant.

                             In addition, this option becomes exercisable in full if your service
                             as an employee, consultant or director of the Company or a
                             subsidiary of the Company terminates because of death. If your
                             service as an employee, consultant or director of the Company
                             (or a subsidiary of the Company) terminates because of total and permanent
                             disability, then the exercisable portion of this option will be
                             determined by adding 12 months to your actual period of service.

                             Except for the acceleration provisions specified in the grant, no
                             additional shares become exercisable after your service as an
                             employee, consultant or director of the Company or a subsidiary of the
                             Company has terminated for any reason.

Term                         This option expires in any event at the close of business at Company
                             headquarters on the day before the 10th anniversary of the Date of Grant,
                             as shown in the Notice of Stock Option Grant. (It will expire earlier if
                             your service terminates, as described below.)

Regular                      If your service as an employee, consultant or director of
Termination                  the Company or a subsidiary of the Company terminates for any reason except
                             death or total and permanent disability, then this option will expire at
                             the close of business at Company headquarters on the date three months
                             after your termination date. The Company determines when your service
                             terminates for this purpose.

Death                        If you die as an employee, consultant or director of the Company or a
                             subsidiary of the Company, then this option will expire at the close
                             of business at Company headquarters on the date 12 months after
                             the date of death.

Disability                   If your service as an employee, consultant or director of the Company
                             or a subsidiary of the Company terminates because of your total and
                             permanent disability, then this option will expire at the close of business
                             at Company headquarters on the date six months after your termination date.
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                             For all purposes under this Agreement, "total and permanent disability" means
                             that you are unable to engage in any substantial gainful activity by reason
                             of any medically determinable physical or mental impairment which can be
                             expected to result in death or which has lasted, or can be expected to
                             last, for a continuous period of not less than one year.

Leaves of Absence            For purposes of this option, your service does not terminate
                             when you go on a military leave, a sick leave or another bona fide leave of
                             absence, if the leave was approved by the Company in writing and if
                             continued crediting of service is required by the terms of the leave or by
                             applicable law. But your service terminates when the approved leave ends,
                             unless you immediately return to active work.

Restrictions on Exercise     The Company will not permit you to exercise this option if the issuance of shares at
                             that time would violate any law or regulation.

Notice of Exercise           When you wish to  exercise  this  option,  you must  notify the  Company by filing the
                             proper  "Notice of Exercise"  form at the address given on the form.  Your notice must
                             specify how many shares you wish to  purchase.  Your notice must also specify how your
                             shares should be registered  (in your name only or in your and your spouse's  names as
                             community  property or as joint tenants with right of  survivorship).  The notice will
                             be effective when it is received by the Company.

                             If someone else wants to exercise this option after your death, that person
                             must prove to the Company's satisfaction that he or she is entitled to do so.


Form of Payment              When you submit your notice of exercise, you must include payment of the
                             option exercise price for the shares you are purchasing. Payment may be made
                             in one (or a combination of two or more) of the following forms:

                             .    Your personal check, a cashier's check or a money order

                             .    Certificates for shares of Company stock that you own, along with
                                  any forms needed to effect a transfer of those shares to the
                                  Company. The value of the shares, determined as of the effective
                                  date of the option exercise, will be applied to the option
                                  exercise price. Instead of surrendering shares of Company stock,
                                  you may attest to the ownership of those shares on a form
                                  provided by the Company and have the same number of shares
                                  subtracted from the option shares issued to you. However, you may
                                  not surrender, or attest to the ownership of, shares of Company
                                  stock in payment of the exercise price if your action would cause
                                  the Company to recognize compensation expense (or additional
                                  compensation expense) with respect to this option for financial
                                  reporting purposes.
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                             .    Irrevocable directions to a securities broker
                                  approved by the Company to sell all or part of
                                  your option shares and to deliver to the
                                  Company from the sale proceeds an amount
                                  sufficient to pay the option exercise price
                                  and any withholding taxes. (The balance of the
                                  sale proceeds, if any, will be delivered to
                                  you.) The directions must be given by signing
                                  a special "Notice of Exercise" form provided
                                  by the Company.

                             .    Irrevocable directions to a securities broker
                                  or lender approved by the Company to pledge
                                  option shares as security for a loan and to
                                  deliver to the Company from the loan proceeds
                                  an amount sufficient to pay the option
                                  exercise price and any withholding taxes. The
                                  directions must be given by signing a special
                                  "Notice of Exercise" form provided by the
                                  Company.

Withholding Taxes and        You will not be allowed to exercise this option
Stock Withholding            unless you make arrangements acceptable to the
                             Company to pay any withholding taxes that may be
                             due as a result of the option exercise. These
                             arrangements may include withholding shares of
                             Company stock that otherwise would be issued to you
                             when you exercise this option. The value of these
                             shares, determined as of the effective date of the
                             option exercise, will be applied to the withholding
                             taxes.

Restrictions on Resale       By signing this Agreement, you agree not to sell
                             any option shares at a time when applicable laws,
                             Company policies or an agreement between the
                             Company and its underwriters prohibit a sale. This
                             restriction will apply as long as you are an
                             employee, consultant or director of the Company or
                             a subsidiary of the Company.

Transfer of Option           Prior to your death, only you may exercise this
                             option. You cannot transfer or assign this option.
                             For instance, you may not sell this option or use
                             it as security for a loan. If you attempt to do any
                             of these things, this option will immediately
                             become invalid. You may, however, dispose of this
                             option in your will or a beneficiary designation.

                             Regardless of any marital property settlement
                             agreement, the Company is not obligated to honor a
                             notice of exercise from your former spouse, nor is
                             the Company obligated to recognize your former
                             spouse's interest in your option in any other way.

Retention Rights             Neither your option nor this Agreement give you the
                             right to be retained by the Company or a subsidiary
                             of the Company in any capacity. The Company and its
                             subsidiaries reserve the right to terminate your
                             service at any time, with or without cause.

Committee                    This Agreement  shall be  administered  by the
                             Committee.  The Committee shall consist exclusively
                             of two or more directors of the Company, who shall
                             be appointed by the Board. In addition, the
                             composition of the Committee shall satisfy:
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                         (a) Such requirements as the Securities and Exchange
                    Commission may establish for administrators acting under
                    plans intended to qualify for exemption under Rule 16b-3 (or
                    its successor) under the Exchange Act; and

                         (b) Such requirements as the Internal Revenue Service
                    may establish for outside directors acting under plans
                    intended to qualify for exemption under section 162(m)(4)(C)
                    of the Code.

                    The Committee's determinations under the Plan shall be final
                    and binding on all persons.

Stockholder         You, or your estate or heirs, have no rights as a
Rights              stockholder of the Company until you have exercised this
                    option by giving the required notice to the Company and
                    paying the exercise price. No adjustments are made for
                    dividends or other rights if the applicable record date
                    occurs before you exercise this option, except as described
                    below.

Adjustments         In the event of a subdivision of the outstanding Common
                    Shares, a declaration of a dividend payable in Common
                    Shares, a declaration of a dividend payable in a form other
                    than Common Shares in an amount that has a material effect
                    on the price of Common Shares, a combination or
                    consolidation of the outstanding Common Shares (by
                    reclassification or otherwise) into a lesser number of
                    Common Shares, a recapitalization, a spin-off or a similar
                    occurrence, the Committee shall make such adjustments as it,
                    in its sole discretion, deems appropriate in one or more of
                    (a) the number of Common Shares covered by each outstanding
                    Option or (b) the Exercise Price under each outstanding
                    Option. Except as provided in this paragraph, an Optionee
                    shall have no rights by reason of any issue by the Company
                    of stock of any class or securities convertible into stock
                    of any class, any subdivision or consolidation of shares of
                    stock of any class, the payment of any stock dividend or any
                    other increase or decrease in the number of shares of stock
                    of any class. To the extent not previously exercised,
                    Options shall terminate immediately prior to the dissolution
                    or liquidation of the Company.

                    In the event that the Company is a party to a merger or
                    other reorganization, outstanding Options and Restricted
                    Shares shall be subject to the agreement of merger or
                    reorganization. Such agreement shall provide for (a) the
                    continuation of the outstanding Awards by the Company, if
                    the Company is a surviving corporation, (b) the assumption
                    of the outstanding Awards by the surviving corporation or
                    its parent or subsidiary, (c) the substitution by the
                    surviving corporation or its parent or subsidiary of its own
                    awards for the outstanding Awards, (d) full
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                    exercisability or vesting and accelerated expiration of the
                    outstanding Awards or (e) settlement of the full value of
                    the outstanding Awards in cash or cash equivalents followed
                    by cancellation of such Awards.

 Modification       Within the limitations of this Agreement, the Committee may
 or Assumption      modify, extend or assume outstanding options or may accept
 of Options         the cancellation of outstanding options (whether granted by
                    the Company or by another issuer) in return for the grant of
                    new options for the same or a different number of shares and
                    at the same or a different exercise price. The foregoing
                    notwithstanding, no modification of an Option shall, without
                    the consent of the Optionee, alter or impair his or her
                    rights or obligations under such Option. The Committee may
                    at any time (a) offer to buy out for a payment in cash or
                    cash equivalents an Option previously granted or (b)
                    authorize an Optionee to elect to cash out an Option
                    previously granted, in either case at such time and based
                    upon such terms and conditions as the Committee shall
                    establish.

Deferral of         The Committee (in its sole discretion) may permit or require
Delivery of         an Optionee to have Common Shares that otherwise would be
Shares              delivered to such Optionee as a result of the exercise of an
                    Option converted into amounts credited to a deferred
                    compensation account established for such Optionee by the
                    Committee as an entry on the Company's books. Such amounts
                    shall be determined by reference to the Fair Market Value of
                    such Common Shares as of the date when they otherwise would
                    have been delivered to such Optionee. A deferred
                    compensation account established under this paragraph may be
                    credited with interest or other forms of investment return,
                    as determined by the Committee. An Optionee for whom such an
                    account is established shall have no rights other than those
                    of a general creditor of the Company. Such an account shall
                    represent an unfunded and unsecured obligation of the
                    Company and shall be subject to the terms and conditions of
                    the applicable agreement between such Optionee and the
                    Company. If the conversion of Options is permitted or
                    required, the Committee (in its sole discretion) may
                    establish rules, procedures and forms pertaining to such
                    conversion, including (without limitation) the settlement of
                    deferred compensation accounts established under this
                    paragraph.

Definitions         .    Affiliate" means any entity other than a Subsidiary, if
                         the Company and/or one or more Subsidiaries own not
                         less than 50% of such entity.

                    .    "Award" means any award of an Option or a Restricted
                         Share under the Plan.

                    .    "Board" means the Company's Board of Directors, as
                         constituted from time to time.

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               . "Change in Control" shall mean:

                         (a) The consummation of a merger or consolidation of
                    the Company with or into another entity or any other
                    corporate reorganization, if persons who were not
                    stockholders of the Company immediately prior to such
                    merger, consolidation or other reorganization own
                    immediately after such merger, consolidation or other
                    reorganization 50% or more of the voting power of the
                    outstanding securities of each of (i) the continuing or
                    surviving entity and (ii) any direct or indirect parent
                    corporation of such continuing or surviving entity;

                         (b) The sale, transfer or other disposition of all or
                    substantially all of the Company's assets;

                         (c) A change in the composition of the Board, as a
                    result of which 50% or fewer of the incumbent directors are
                    directors who either (i) had been directors of the Company
                    on the date 24 months prior to the date of the event that
                    may constitute a Change in Control (the "original
                    directors") or (ii) were elected, or nominated for election,
                    to the Board with the affirmative votes of at least a
                    majority of the aggregate of the original directors who were
                    still in office at the time of the election or nomination
                    and the directors whose election or nomination was
                    previously so approved; or

                         (d) Any transaction as a result of which any person is
                    the "beneficial owner" (as defined in Rule 13d-3 under the
                    Exchange Act), directly or indirectly, of securities of the
                    Company representing at least 50% of the total voting power
                    represented by the Company's then outstanding voting
                    securities. For purposes of this Subsection (d), the term
                    "person" shall have the same meaning as when used in
                    sections 13(d) and 14(d) of the Exchange Act but shall
                    exclude (i) a trustee or other fiduciary holding securities
                    under an employee benefit plan of the Company or of a Parent
                    or Subsidiary and (ii) a corporation owned directly or
                    indirectly by the stockholders of the Company in
                    substantially the same proportions as their ownership of the
                    common stock of the Company.

               A transaction shall not constitute a Change in Control if its
               sole purpose is to change the state of the Company's
               incorporation or to create a holding company that will be owned
               in substantially the same

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               proportions by the persons who held the Company's securities
               immediately before such transaction.

               o    "Code" means the Internal Revenue Code of 1986, as amended.

               o    "Committee" means a committee of the Board, as described in
                    Article 2.

               o    "Common Share" means one share of the common stock of the
                    Company.

               o    "Company" means Redback Networks Inc., a Delaware
                    corporation.

               o    "Consultant" means a consultant or adviser who provides bona
                    fide services to the Company, a Parent, a Subsidiary or an
                    Affiliate as an independent contractor. Service as a
                    Consultant shall be considered employment for all purposes
                    of this Agreement.

               o    "Employee" means a common-law employee of the Company, a
                    Parent, a Subsidiary or an Affiliate.

               o    "Exchange Act" means the Securities Exchange Act of 1934, as
                    amended.

               o    "Exercise Price" means the amount for which one Common Share
                    may be purchased upon exercise of such Option, as specified
                    in the applicable Stock Option Agreement.

               o    "Fair Market Value" means the market price of Common Shares,
                    determined by the Committee in good faith on such basis as
                    it deems appropriate. Whenever possible, the determination
                    of Fair Market Value by the Committee shall be based on the
                    prices reported in The Wall Street Journal. Such
                                       -----------------------
                    determination shall be conclusive and binding on all
                    persons.

               o    "NSO" means a stock option not described in sections 422 or
                    423 of the Code.

               o    "Option" means an NSO granted under this Agreement and
                    entitling the holder to purchase Common Shares.

               o    "Optionee" means an individual or estate who holds an
                    Option.

               o    "Outside Director" shall mean a member of the Board who is
                    not an Employee. Service as an Outside Director shall be

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                         considered employment for all purposes of this
                         Agreement.

                    o    "Parent" means any corporation (other than the Company)
                         in an unbroken chain of corporations ending with the
                         Company, if each of the corporations other than the
                         Company owns stock possessing 50% or more of the total
                         combined voting power of all classes of stock in one of
                         the other corporations in such chain. A corporation
                         that attains the status of a Parent on a date after the
                         adoption of this Agreement shall be considered a Parent
                         commencing as of such date.

                    o    "Subsidiary" means any corporation (other than the
                         Company) in an unbroken chain of corporations beginning
                         with the Company, if each of the corporations other
                         than the last corporation in the unbroken chain owns
                         stock possessing 50% or more of the total combined
                         voting power of all classes of stock in one of the
                         other corporations in such chain.

Applicable Law      This Agreement will be interpreted and enforced under the
                    laws of the State of Delaware (without regard to their
                    choice-of-law provisions).

The Plan            This Agreement constitutes the entire understanding between
and Other           you and the Company regarding this option. Any prior
Agreements          agreements, commitments or negotiations concerning this
                    option are superseded. This agreement, signed by both
                    parties.

     BY SIGNING THE COVER SHEET OF THIS AGREEMENT, YOU AGREE TO ALL OF THE
             TERMS AND CONDITIONS DESCRIBED ABOVE AND IN THE PLAN.

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