EXHIBIT (a)(8)

            [FORM OF IRREVOCABLE STANDING ORDER TO SELL SHARES]

                  I, __________________________, have been granted
_____________ shares of restricted stock by Sycamore Networks, Inc.
("Sycamore"), that are evidenced by a restricted stock agreement between me
and Sycamore (the "Agreement"), a copy of which is attached. Provided that
I remain employed by Sycamore or one of its subsidiaries and do not have a
change in service, the shares vest according to the vesting schedule set
forth on the restricted stock agreement attached hereto.

                  Pursuant to the terms of the Agreement and as a condition
of my receipt of the Shares (as defined below), I understand that on each
vesting date I will recognize taxable ordinary income on the entire
installment of shares of restricted stock vesting on that date (the
"Shares") and that a sufficient number of the Shares will be deposited into
my account at [broker] to be sold to fulfill my withholding tax obligations
and applicable broker commission. Therefore, I HEREBY DIRECT [BROKER] TO
SELL, AT THE MARKET PRICE AND ON EACH VESTING DATE SET FORTH ON THE
RESTRICTED STOCK AGREEMENT ATTACHED HERETO (OR THE FIRST BUSINESS DAY
THEREAFTER IF A VESTING DATE SHOULD FALL ON A DAY WHEN THE NASDAQ STOCK
MARKET, OR OTHER EXCHANGE UPON WHICH SYCAMORE'S COMMON STOCK IS THEN
TRADED, IS CLOSED), THE NUMBER OF SHARES THAT SYCAMORE INFORMS [BROKER] IS
SUFFICIENT TO SATISFY THE APPLICABLE WITHHOLDING TAXES AND BROKER
COMMISSION, IF NECESSARY, WHICH SHALL BE CALCULATED BASED ON THE CLOSING
PRICE OF SYCAMORE'S COMMON STOCK ON EACH VESTING DATE. I understand that
[broker] will remit the proceeds, net of broker commissions, to Sycamore
for payment of the withholding taxes due.

                  I understand that if I make a timely election under
Section 83(b) of the Internal Revenue Code, to recognize tax with respect
to this grant of restricted stock and provide Sycamore with (1) a copy of
such election, (2) proof of filing such election and (3) a cash payment in
the amount Sycamore anticipates is required to fulfill the tax withholding
obligations with respect to the restricted stock, Sycamore shall not
enforce its rights under this Irrevocable Standing Order to Sell Shares.

                  I hereby agree to indemnify and hold [broker] harmless
from and against all losses, liabilities, damages, claims and expenses,
including reasonable attorneys' fees and court costs, arising out of any
(i) negligent act, omission or willful misconduct by Sycamore in carrying
out actions pursuant to the third sentence of the second preceding
paragraph and (ii) any action taken or omitted by [broker] in good faith
reliance upon instructions herein or upon instructions or information
transmitted to [broker] by Sycamore pursuant to the third sentence of the
second preceding paragraph.

                  I understand and agree that by signing below, I am making
an Irrevocable Standing Order to Sell Shares that will remain in effect
until all of the shares of restricted stock held by me have vested. I
intend this Irrevocable Standing Order to sell shares to be irrevocable,
and will take such further action and execute such other instruments as may
be necessary to effectuate the intent of this Irrevocable Standing Order to
sell Shares. I also agree that this Irrevocable Standing Order to Sell
Shares is in addition to and subject to the terms and conditions of any
Account Agreement that I enter into with [broker].

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Signature                                Signature (Additional Account Holder)

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Print Name                               Print Name

Dated:  ______, 2001                     Dated:  ______, 2001