> I had a doubt on History-info header present in Sip 18x Responses. > > Are the History-info headers UAC received in 18x response useful to an > application or user ? > > If yes can you please quote an example where its useful to an > application/user . > > How should the UAC's treat these HI headers? > > Thanks, > Divya.
RFC 4244 Section 4.3.1. User Agent Client (UAC) Behavior With the exception of the processing of a 3xx response described above, the processing of the History-Info header received in the Response is application specific and outside the scope of this document. However, the validity of the information SHOULD be ensured prior to any application usage. For example, the entries MAY be evaluated to determine gaps in indices, which could indicate that an entry has been maliciously removed or removed for privacy reasons. Either way, an application MAY want to be aware of potentially missing information. The original draft (draft-ietf-sip-history-info-00) talked about 183 responses, this was removed in the subsequent versions: 2.3.3.2 Processing History-Info in Responses A proxy that receives a Request with the HistInfo option tag in the Supported header, and depending upon a local policy supporting the capture of History-Info, SHOULD return captured History-Info in subsequent, provisional and final responses to the Request. A 183 response MAY be sent explicitly for the purposes of conveying History-Info prior to the final response. Regards, Bhaskar _______________________________________________ Sip-implementors mailing list Sip-implementors@lists.cs.columbia.edu https://lists.cs.columbia.edu/cucslists/listinfo/sip-implementors
