Say I want to transfer someone's call. I send a REFER, establishing an implicit subscription with the transferee. The transferee tells me "Subscription-State: pending;expires=60". The transferee takes longer than, say, 45 seconds to transfer, and so I try to refresh the subscription.
RFC 3515 says The agent issuing the REFER may extend its subscription using the subscription refresh mechanisms described in [2]. [2] here is RFC 3265, which says 3.1.4.2. Refreshing of Subscriptions At any time before a subscription expires, the subscriber may refresh the timer on such a subscription by sending another SUBSCRIBE request on the same dialog as the existing subscription, and with the same "Event" header "id" parameter (if one was present in the initial subscription). The handling for such a request is the same as for the initial creation of a subscription except as described below. Does this mean that I send a SUBSCRIBE to refresh a REFER's subscription? That seems wrong, since RFC 3515 also says (section 2.4.4) REFER is the only mechanism that can create a subscription to event refer. If a SUBSCRIBE request for event refer is received for a subscription that does not already exist, it MUST be rejected with a 403. So does that mean that I follow the procedure laid out in RFC 3265, with the word "SUBSCRIBE" scratched out and "REFER" written in in crayon? frank _______________________________________________ Sip-implementors mailing list [email protected] https://lists.cs.columbia.edu/cucslists/listinfo/sip-implementors
