From: Robert Sparks <[EMAIL PROTECTED]> Here's a really interesting one.
Lots of people are sending REFER with a Refer-To URI that has an embedded Replaces header. This is what we're specifying in cc-transfer. Nobody puts Require: replaces in the REFER request (and I don't think they should - does anybody disagree?) However, very few implementations are putting Require: replaces in the triggered INVITE. They're copying the Replaces header into the INVITE though. That's OK, the UA that processes the REFER isn't *supposed* to put a "Require: replaces" header into the generated INVITE unless there is a "?Require=replaces" header parameter in the Refer-To URI. (Because otherwise the sender of the REFER couldn't specify "I want you to send an INVITE with a Replaces header but without a 'Require: replaces' header. Such an INVITE is clearly legal and its effects are well-defined, although not very useful.) This will cause very wrong things to happen if that triggered INVITE forks. Or if the intended destination of the INVITE doesn't happen to support Replaces. Hence, the sender of the REFER should always include "?Refer=replaces" in the Refer-To URI. Dale _______________________________________________ Sip mailing list https://www1.ietf.org/mailman/listinfo/sip This list is for NEW development of the core SIP Protocol Use [EMAIL PROTECTED] for questions on current sip Use [EMAIL PROTECTED] for new developments on the application of sip
