%% You should probably cite rfc6809 instead of this I-D. @techreport{ietf-sipcore-proxy-feature-02, number = {draft-ietf-sipcore-proxy-feature-02}, type = {Internet-Draft}, institution = {Internet Engineering Task Force}, publisher = {Internet Engineering Task Force}, note = {Work in Progress}, url = {https://datatracker.ietf.org/doc/draft-ietf-sipcore-proxy-feature/02/}, author = {Christer Holmberg and Ivo Sedlacek and Hadriel Kaplan}, title = {{Indication of features supported by proxy}}, pagetotal = 18, year = 2012, month = may, day = 9, abstract = {This specification creates a new IANA registry, "SIP Feature Cap Registry", which is used to register indicators, "SIP feature caps", used by SIP entities to indicate support of features and capabilities, in cases where the Contact header field contains a URI that does not represent the SIP entity that wants to indicate support of its features and capabilities. This specification also defines a new SIP header field, Feature-Caps, that can be used by SIP entities to convey information about supported features and capabilities, using SIP feature caps.}, }