> Is this mandatory to have support for replaces parameter to support > REFER request?
No; RFC 3515 does not madate support for Replaces. And RFC 3861 section 2 indicates the following. "Although the Replaces header is frequently used in combination with the REFER [8] method as used in a Transfer [12], they may be used independently." > Means If Supported: replaces is not present in the User Agent side . Then > that user will not support REFER request. The REFER request is containing > Replaces-to header having Replaces parameter. So in this case the Use Agent > will not support that REFER request? I assume that you mean Refer-To instead of Replaces-to. RFC 3515 section 2.1 shows an example of a Refer-To with a Replaces header embedded within the sip-uri. RFC 3261 section 19 discusses what should occur. " An implementation SHOULD treat the presence of any headers or body parts in the URI as a desire to include them in the message, and choose to honor the request on a per-component basis." Notice that the party that received the Refer-To does not need to support Replaces. However, it is possible that it won't honor the request to include unknown headers within the resulting INVITE. Thus the Replaces might not be received by the Refer-To target. _______________________________________________ Sip-implementors mailing list Sip-implementors@lists.cs.columbia.edu https://lists.cs.columbia.edu/mailman/listinfo/sip-implementors
