Yealink SIP-T48G Administrator's Manual

Also see for Yealink SIP-T48G: Developer's guide Administrator's guide Manual Auto provisioning guide Getting started

Contents

Yealink SIP-T48G Administrator's Manual Manual pdf 285 page image

Appendix273Step Action Descriptionready to receive is specified. The port on which User B isprepared to receive the RTP data isspecified.F2 INVITE—Proxy Server to UserBThe proxy server maps the SIP URI in theTo field to User B. Proxy server forwardsthe INVITE message to User B.F3180 Ringing—User B to ProxyServerUser B sends a SIP 180 Ringing responseto the proxy server. The 180 Ringingresponse indicates that the user is beingalerted.F4180 Ringing—Proxy Server toUser AThe proxy server forwards the 180Ringing response to User A. User Ahears the ring-back tone indicating thatUser B is being alerted.F5CANCEL—User A to ProxyServerUser A sends a SIP CANCEL request tothe proxy server after not receiving anappropriate response within the timeallocated in the INVITE request. The SIPCANCEL request indicates that User Awants to disconnect the call.F6CANCEL—Proxy Server toUser BThe proxy server forwards the SIPCANCEL request to notify User B thatUser A wants to disconnect the call.F7200 OK—User B to ProxyServerUser B sends a SIP 200 OK response tothe proxy server. The SIP 200 OKresponse indicates that User B hasreceived the CANCEL request.F8200 OK—Proxy Server to UserAThe proxy server forwards the SIP 200OK response to notify User A that theCANCEL request has been processedsuccessfully.The following figure illustrates a successful call setup and call hold. In this scenario, thetwo end users are User A and User B. User A and User B are located at Yealink SIP IPphones.