%% You should probably cite draft-ietf-sipping-sip-offeranswer instead of this I-D. @techreport{sawada-sipping-sip-offeranswer-01, number = {draft-sawada-sipping-sip-offeranswer-01}, type = {Internet-Draft}, institution = {Internet Engineering Task Force}, publisher = {Internet Engineering Task Force}, note = {Work in Progress}, url = {https://datatracker.ietf.org/doc/draft-sawada-sipping-sip-offeranswer/01/}, author = {Takuya Sawada and Paul Kyzivat}, title = {{SIP (Session Initiation Protocol) Usage of Offer/Answer Model}}, pagetotal = 14, year = 2006, month = jun, day = 12, abstract = {SIP utilizes offer/answer model to establish and update multimedia sessions. The descriptions on how to use offer/answer in SIP are dispersed in the multiple RFCs. This document summarizes all the current usage of offer/answer model in SIP communication.}, }