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Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
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 TWSM7vrzLADbmYQaionwg5sDW3P6oaM5D3tdezXMm7z1T+B+twIDAQAB
MIC-Info: RSA-MD5,RSA,
 NsgexSO94GgqqQFRsaTA5km8atkB/wml2ZN5EvdupFOsfFw2exCapNe722io3Oi0
 VHemtbTITwbylsKwfzLO3Q==

<SEC-DOCUMENT>0001237622-03-000001.txt : 20031231
<SEC-HEADER>0001237622-03-000001.hdr.sgml : 20031231
<ACCEPTANCE-DATETIME>20031231160830
ACCESSION NUMBER:		0001237622-03-000001
CONFORMED SUBMISSION TYPE:	3
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20031229
FILED AS OF DATE:		20031231

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			ASPEN PARTNERS SERIES A
		CENTRAL INDEX KEY:			0001237622
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		3
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-25853
		FILM NUMBER:		031080684

	MAIL ADDRESS:	
		STREET 1:		C/O ASPEN ADVISORS LLC
		STREET 2:		152 W 57TH ST
		CITY:			NEW YORK
		STATE:			NY
		ZIP:			10019

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			REDBACK NETWORKS INC
		CENTRAL INDEX KEY:			0001081290
		STANDARD INDUSTRIAL CLASSIFICATION:	SERVICES-COMPUTER INTEGRATED SYSTEMS DESIGN [7373]
		IRS NUMBER:				770438443
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		300 HOLGER WAY
		CITY:			SAN JOSE
		STATE:			CA
		ZIP:			95134
		BUSINESS PHONE:		4087505000

	MAIL ADDRESS:	
		STREET 1:		300 HOLGER WAY
		CITY:			SAN JOSE
		STATE:			CA
		ZIP:			95134
</SEC-HEADER>
<DOCUMENT>
<TYPE>3
<SEQUENCE>1
<FILENAME>primary_doc.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
<XML>
<?xml version="1.0"?>

<ownershipDocument>

    <schemaVersion>X0201</schemaVersion>

    <documentType>3</documentType>

    <periodOfReport>2003-12-29</periodOfReport>


    <noSecuritiesOwned>0</noSecuritiesOwned>

    <issuer>
        <issuerCik>0001081290</issuerCik>
        <issuerName>REDBACK NETWORKS INC</issuerName>
        <issuerTradingSymbol>RBAKQ</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001237622</rptOwnerCik>
            <rptOwnerName>ASPEN PARTNERS SERIES A</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O ASPEN ADVISORS LLC</rptOwnerStreet1>
            <rptOwnerStreet2>152 WEST 57TH STREET, 46TH FLOOR</rptOwnerStreet2>
            <rptOwnerCity>NEW YORK</rptOwnerCity>
            <rptOwnerState>NY</rptOwnerState>
            <rptOwnerZipCode>10019</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>

        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>19424700</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeHolding>

    </nonDerivativeTable>



    <ownerSignature>
        <signatureName>Aspen Partners Series A, Aspen Capital LLC, General Partner, Nikos Hecht, Managing Member</signatureName>
        <signatureDate>2003-12-31</signatureDate>
    </ownerSignature>

</ownershipDocument>

</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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