Administrator’s Guide for SIP-T2 Series/T19(P) E2/T4 Series/T5 Series/CP860/CP920 IP Phones 
1056 
  draft-levy -sip-diversion-08.txt—Diversion Indication in SIP 
  draft-ietf-sipping-cc-conferencing-03.txt—SIP Call Control - Conferencing for User Agents 
  draft-ietf-sipping-cc-conferencing-05.txt—Connection Reuse in the Session Initiation 
Protocol (SIP) 
  draft-ietf-sipping-rtcp-summary-02.txt—Session Initiation Protocol Package for Voice 
Quality Reporting Event 
  draft-ietf-sip-connect-reuse-06.txt—Connection Reuse in the Session Initiation Protocol 
(SIP) 
  draft-ietf-bliss-shared-appearances-15.txt—Shared Appearances of a Session Initiation 
Protocol (SIP) Address of Record (AOR) 
To find the applicable Request for Comments (RFC) document, go to 
http://www.ietf.org/rfc.html and enter the RFC number. 
SIP Request 
The following SIP request messages are supported: 
Yealink IP phones support 
mid-call changes such as 
placing a call on hold as 
signaled by a new INVITE 
that contains an existing 
Call-ID.