> RFC 3515 specifies that Contact Header is mandatory > in REFER message. > > If Contact Header is missing in REFER, can we populate > its value from the "From" Header?
The REFER is malformed; thus you can basically be as strict or lenient as you desire. If the REFER was within a dialog and you don't want to return a 400 response, you can process the REFER as though there was no Contact modification. If the REFER was outside of dialog, returning a 400 response is best. However if you want to be lenient and assume Contact rules similar to rfc2543 (I don't recommend it), yes you can assume the sender didn't provide a Contact because the From's uri was adequate for routing and use as request-uri for the corresponding NOTIFY. _______________________________________________ Sip-implementors mailing list [email protected] https://lists.cs.columbia.edu/cucslists/listinfo/sip-implementors
