<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0202</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2005-03-11</periodOfReport>

    <issuer>
        <issuerCik>0001120295</issuerCik>
        <issuerName>IXIA</issuerName>
        <issuerTradingSymbol>XXIA</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001134221</rptOwnerCik>
            <rptOwnerName>TECHNOLOGY CAPITAL GROUP SA</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>5, BOULEVARD DE LA FOIRE</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>L-1528 LUXEMBOURG</rptOwnerCity>
            <rptOwnerState>N4</rptOwnerState>
            <rptOwnerZipCode></rptOwnerZipCode>
            <rptOwnerStateDescription>LUXEMBOURG</rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001317318</rptOwnerCik>
            <rptOwnerName>Compagnie Fiduciaire Trustees Limited, as Trustee of the Capital Group Trust under Trust Deed dated February 8, 2005</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>P.O. BOX 801</rptOwnerStreet1>
            <rptOwnerStreet2>VICTORIA CHAMBERS, 1-3 ESPLANADE</rptOwnerStreet2>
            <rptOwnerCity>ST HELIER, JERSEY CHANNEL ISL</rptOwnerCity>
            <rptOwnerState></rptOwnerState>
            <rptOwnerZipCode>JE4 0SZ</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2005-03-11</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>S</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>50000</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>18.9000</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>24097000</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value></value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <footnotes></footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>Pierre Lentz, as a Director of Technology Capital Group S.A.</signatureName>
        <signatureDate>2005-03-15</signatureDate>
    </ownerSignature>

    <ownerSignature>
        <signatureName>John Seil, as a Director of Technology Capital Group S.A.</signatureName>
        <signatureDate>2005-03-15</signatureDate>
    </ownerSignature>

    <ownerSignature>
        <signatureName>Paul W. Elliott, as Director of Compagnie Fiduciaire Trustees Limited, Trustee of the Capital Group under Trust Deed Dated February 8, 2005</signatureName>
        <signatureDate>2005-03-15</signatureDate>
    </ownerSignature>
</ownershipDocument>
