@techreport{barnes-sip-rfc4244bis-00, number = {draft-barnes-sip-rfc4244bis-00}, type = {Internet-Draft}, institution = {Internet Engineering Task Force}, publisher = {Internet Engineering Task Force}, note = {Work in Progress}, url = {https://datatracker.ietf.org/doc/draft-barnes-sip-rfc4244bis/00/}, author = {Mary Barnes and Francois Audet}, title = {{An Extension to the Session Initiation Protocol (SIP) for Request History Information}}, pagetotal = 49, year = 2009, month = mar, day = 4, abstract = {This document defines a standard mechanism for capturing the history information associated with a Session Initiation Protocol (SIP) request. This capability enables many enhanced services by providing the information as to how and why a call arrives at a specific application or user. This document defines a new optional SIP header, History-Info, for capturing the history information in requests.}, }