Transient Name Identifier

Transient name identifiers have the following properties:

Property

Value

longevity

transient, configurable lifetime

transparency

opaque

targeted

no

revokable

yes, ID automatically revoked after a defined number of minutes

reassignable

yes

Define the Attribute

Transient name identifier attributes are created in two steps:

  1. Create a TransientId or CryptoTransientId attribute definition that generates the transient ID value.
  2. Attach SAML 1 Name Identifier and SAML 2 NameID attribute encoder to the attribute.
<resolver:AttributeDefinition id="transientId" xsi:type="TransientId"
                              xmlns="urn:mace:shibboleth:2.0:resolver:ad">

    <resolver:AttributeEncoder xsi:type="SAML1StringNameIdentifier"
                               xmlns="urn:mace:shibboleth:2.0:attribute:encoder"
                               nameFormat="urn:mace:shibboleth:1.0:nameIdentifier" />

    <resolver:AttributeEncoder xsi:type="SAML2StringNameID"
                               xmlns="urn:mace:shibboleth:2.0:attribute:encoder"
                               nameFormat="urn:oasis:names:tc:SAML:2.0:nameid-format:transient" />
</resolver:AttributeDefinition>

The name format for a transient ID in SAML 1 is urn:mace:shibboleth:1.0:nameIdentifier and in SAML 2 is urn:oasis:names:tc:SAML:2.0:nameid-format:transient

Release the Attribute

Finally, define an attribute filter policy that releases the transient ID to the intended relying parties. Since transient IDs are opaque, and thus not personally identifiable, they are safe to release to anyone. Therefore the following attribute filter policy is suggested but others may be used at the deployer's discretion.

<AttributeFilterPolicy id="releaseTransientIdToAnyone">

    <PolicyRequirementRule xsi:type="basic:ANY" />

    <AttributeRule attributeID="transientId">
        <PermitValueRule xsi:type="basic:ANY" />
    </AttributeRule>

</AttributeFilterPolicy>