SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549

                                    FORM 8-K

                                 CURRENT REPORT
                     Pursuant to Section 13 or 15(d) of the
                         Securities Exchange Act of 1934


                                November 11, 2003
                Date of Report (Date of earliest event reported)

                             SYCAMORE NETWORKS, INC.
             (Exact name of registrant as specified in its charter)


        Delaware                  000-27273                  04-3410558
----------------------------     -----------             -------------------
(State or other jurisdiction     (Commission               (IRS Employer
    of incorporation)            file number)            Identification No.)

                                  220 Mill Road
                        Chelmsford, Massachusetts 01824
                    (Address of principal executive offices)
                                   (Zip code)

       Registrant's telephone number, including area code: (978) 250-2900

                                 Not Applicable
          (Former name or former address, if changed since last report)

<PAGE>



Item 12: Results of Operations and Financial Condition

On November 11, 2003, the Registrant reported its first quarter results for the
period ended October 25, 2003. A copy of the press release issued by the
Registrant on November 11, 2003 concerning the foregoing results is furnished
herewith as Exhibit 99.1 and is incorporated herein by reference and the
transcript for the conference call with respect thereto is furnished herewith
as Exhibit 99.2 and is incorporated herein by reference.

The information contained herein and in the accompanying exhibits shall not be
incorporated by reference into any filing of the Registrant, whether made
before or after the date hereof, regardless of any general incorporation
language in such filing, unless expressly incorporated by specific reference
into such filing. The information in this report, including the exhibits
hereto, shall not be deemed to be "filed" for purposes of Section 18 of the
Securities Exchange Act of 1934, as amended, or otherwise subject to the
liabilities of that section or Sections 11 and 12(a)(2) of the Securities Act
of 1933, as amended.

The Registrant provides pro forma financial data in addition to providing
financial results in accordance with generally accepted accounting principles
(GAAP). These measures are not in accordance with, or an alternative for GAAP,
and may be different from pro forma measures used by other companies. The
reconciliation between GAAP results and the pro forma results is provided in a
table immediately following the Unaudited Consolidated Statements of Operations
included with Exhibit 99.1. The items excluded from pro forma results have one
or more of the following characteristics: their magnitude and timing is largely
outside of the Registrant's control; they are unrelated to the ongoing
operation of the business in the ordinary course; they are unusual, and the
Registrant does not expect them to occur in the ordinary course of business; or
they are non-operational, non-cash expenses involving stock option grants
primarily in connection with the Registrant's initial public offering and
acquisitions.

The non-GAAP financial data is provided to enhance the user's overall
understanding of the Registrant's current financial performance and its
prospects for the future. Specifically, the Registrant believes the non-GAAP
results provide useful information to both management and investors by excluding
certain expense and income items that the Registrant believes are not indicative
of the Registrant's core operating results because such charges are associated
with past events and are not related to current operations. In addition, since
the Registrant has historically reported non-GAAP results to the investment
community, the Registrant believes the inclusion of non-GAAP numbers provides
consistency in its financial reporting. Further, these non-GAAP results are one
of the primary indicators management uses for planning and forecasting in future
periods. The non-GAAP financial data should be considered in addition to, not as
a substitute for or as being superior to, operating losses, cash flows, or other
measures of financial performance prepared in accordance with GAAP.
<PAGE>



                                   SIGNATURES


Pursuant to the requirements of the Securities Exchange Act of 1934, the
Registrant has duly caused this report to be signed on its behalf by the
undersigned thereunto duly authorized.



Sycamore Networks, Inc.


/s/ Frances M. Jewels
--------------------------------------
Frances M. Jewels
Chief Financial Officer
(Duly Authorized Officer and Principal
Financial and Accounting Officer)

Dated: November 12, 2003
<PAGE>


                                  EXHIBIT INDEX

Exhibit
Number        Description
-------       -----------

99.1          Press Release of the Registrant, dated November 11, 2003,
              reporting the Registrant's first quarter results for the period
              ended October 25, 2003.

99.2          Transcript for the conference call held by the Registrant on
              November 11, 2003 with respect to the Registrant's first quarter
              results for the period ended October 25, 2003.
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{"company-data": {"conformed-name": "SYCAMORE NETWORKS INC", "cik": "0001092367", "assigned-sic": "3661", "irs-number": "043410558", "state-of-incorporation": "DE", "fiscal-year-end": "0731"}, "filing-values": {"form-type": "8-K", "act": "34", "file-number": "000-27273", "film-number": "03995000"}, "business-address": {"street1": "220 MILL ROAD", "city": "CHELMSFORD", "state": "MA", "zip": "01824", "phone": "9782502900"}, "mail-address": {"street1": "220 MILL ROAD", "city": "CHELMSFORD", "state": "MA", "zip": "01824"}}
SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549

                                    FORM 8-K

                                 CURRENT REPORT
                     Pursuant to Section 13 or 15(d) of the
                         Securities Exchange Act of 1934

                                November 11, 2003
                Date of Report (Date of earliest event reported)

                             SYCAMORE NETWORKS, INC.
             (Exact name of registrant as specified in its charter)

        Delaware                  000-27273                  04-3410558
----------------------------     -----------             -------------------
(State or other jurisdiction     (Commission               (IRS Employer
    of incorporation)            file number)            Identification No.)

                                  220 Mill Road
                        Chelmsford, Massachusetts 01824
                    (Address of principal executive offices)
                                   (Zip code)

       Registrant's telephone number, including area code: (978) 250-2900

                                 Not Applicable
          (Former name or former address, if changed since last report)
Item 12: Results of Operations and Financial Condition

On November 11, 2003, the Registrant reported its first quarter results for the
period ended October 25, 2003. A copy of the press release issued by the
Registrant on November 11, 2003 concerning the foregoing results is furnished
herewith as Exhibit 99.1 and is incorporated herein by reference and the
transcript for the conference call with respect thereto is furnished herewith
as Exhibit 99.2 and is incorporated herein by reference.

The information contained herein and in the accompanying exhibits shall not be
incorporated by reference into any filing of the Registrant, whether made
before or after the date hereof, regardless of any general incorporation
language in such filing, unless expressly incorporated by specific reference
into such filing. The information in this report, including the exhibits
hereto, shall not be deemed to be "filed" for purposes of Section 18 of the
Securities Exchange Act of 1934, as amended, or otherwise subject to the
liabilities of that section or Sections 11 and 12(a)(2) of the Securities Act
of 1933, as amended.

The Registrant provides pro forma financial data in addition to providing
financial results in accordance with generally accepted accounting principles
(GAAP). These measures are not in accordance with, or an alternative for GAAP,
and may be different from pro forma measures used by other companies. The
reconciliation between GAAP results and the pro forma results is provided in a
table immediately following the Unaudited Consolidated Statements of Operations
included with Exhibit 99.1. The items excluded from pro forma results have one
or more of the following characteristics: their magnitude and timing is largely
outside of the Registrant's control; they are unrelated to the ongoing
operation of the business in the ordinary course; they are unusual, and the
Registrant does not expect them to occur in the ordinary course of business; or
they are non-operational, non-cash expenses involving stock option grants
primarily in connection with the Registrant's initial public offering and
acquisitions.

The non-GAAP financial data is provided to enhance the user's overall
understanding of the Registrant's current financial performance and its
prospects for the future. Specifically, the Registrant believes the non-GAAP
results provide useful information to both management and investors by excluding
certain expense and income items that the Registrant believes are not indicative
of the Registrant's core operating results because such charges are associated
with past events and are not related to current operations. In addition, since
the Registrant has historically reported non-GAAP results to the investment
community, the Registrant believes the inclusion of non-GAAP numbers provides
consistency in its financial reporting. Further, these non-GAAP results are one
of the primary indicators management uses for planning and forecasting in future
periods. The non-GAAP financial data should be considered in addition to, not as
a substitute for or as being superior to, operating losses, cash flows, or other
measures of financial performance prepared in accordance with GAAP.
SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the
Registrant has duly caused this report to be signed on its behalf by the
undersigned thereunto duly authorized.

Sycamore Networks, Inc.

/s/ Frances M. Jewels
--------------------------------------
Frances M. Jewels
Chief Financial Officer
(Duly Authorized Officer and Principal
Financial and Accounting Officer)

Dated: November 12, 2003
EXHIBIT INDEX

Exhibit
Number        Description
-------       -----------

99.1          Press Release of the Registrant, dated November 11, 2003,
              reporting the Registrant's first quarter results for the period
              ended October 25, 2003.

99.2          Transcript for the conference call held by the Registrant on
              November 11, 2003 with respect to the Registrant's first quarter
              results for the period ended October 25, 2003.