-----BEGIN PRIVACY-ENHANCED MESSAGE-----
Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
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MIC-Info: RSA-MD5,RSA,
 NSroDo3wpnhLrDWStZEek0CJy6g0jPOuGPhm/KlNtqm2dXNHnVC33bA7+2yM0Kdb
 XKv4G59Y+CVaRBjKjTsBLg==

<SEC-DOCUMENT>0001209191-07-000790.txt : 20070103
<SEC-HEADER>0001209191-07-000790.hdr.sgml : 20070101
<ACCEPTANCE-DATETIME>20070103175739
ACCESSION NUMBER:		0001209191-07-000790
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20061229
FILED AS OF DATE:		20070103
DATE AS OF CHANGE:		20070103

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			OYE KEVIN
		CENTRAL INDEX KEY:			0001208456

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-27273
		FILM NUMBER:		07506231

	BUSINESS ADDRESS:	
		STREET 1:		SYCAMORE NETWORKS INC
		STREET 2:		220 MILL ROAD
		CITY:			CHELMSFORD
		STATE:			MA
		ZIP:			01824

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			SYCAMORE NETWORKS INC
		CENTRAL INDEX KEY:			0001092367
		STANDARD INDUSTRIAL CLASSIFICATION:	TELEPHONE & TELEGRAPH APPARATUS [3661]
		IRS NUMBER:				043410558
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			0731

	BUSINESS ADDRESS:	
		STREET 1:		220 MILL ROAD
		CITY:			CHELMSFORD
		STATE:			MA
		ZIP:			01824
		BUSINESS PHONE:		9782502900

	MAIL ADDRESS:	
		STREET 1:		220 MILL ROAD
		CITY:			CHELMSFORD
		STATE:			MA
		ZIP:			01824
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>doc4.xml
<DESCRIPTION>FORM 4 SUBMISSION
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0202</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2006-12-29</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0001092367</issuerCik>
        <issuerName>SYCAMORE NETWORKS INC</issuerName>
        <issuerTradingSymbol>SCMR</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001208456</rptOwnerCik>
            <rptOwnerName>OYE KEVIN</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O SYCAMORE NETWORKS</rptOwnerStreet1>
            <rptOwnerStreet2>220 MILL ROAD</rptOwnerStreet2>
            <rptOwnerCity>CHELMSFORD</rptOwnerCity>
            <rptOwnerState>MA</rptOwnerState>
            <rptOwnerZipCode>01824</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>VP, Systems and Technology</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <derivativeTable>
        <derivativeTransaction>
            <securityTitle>
                <value>Non-Qualified Stock Option (right to buy)</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>3.40</value>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2006-12-29</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>166667</value>
                </transactionShares>
                <transactionPricePerShare>
                    <footnoteId id="F1"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <value>2005-01-29</value>
            </exerciseDate>
            <expirationDate>
                <value>2012-04-29</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>166667</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>0</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeTransaction>
        <derivativeTransaction>
            <securityTitle>
                <value>Non-Qualified Stock Option (right to buy)</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>3.34</value>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2006-12-29</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>D</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>166667</value>
                </transactionShares>
                <transactionPricePerShare>
                    <footnoteId id="F1"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <value>2005-01-29</value>
            </exerciseDate>
            <expirationDate>
                <value>2012-04-29</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>166667</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>166667</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">The reported transaction involved an increase in the exercise price of an existing option originally granted on April 29, 2002 to increase the exercise price of such option to equal the best currently available estimate of the fair market value of the option on the original date of grant.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/ Kevin Oye</signatureName>
        <signatureDate>2007-01-03</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
-----END PRIVACY-ENHANCED MESSAGE-----