Yealink SIP-T2xP Administrator's Manual page 454

Administrator's Guide for SIP-T2xP and SIP-T19P IP Phones
Method
Allow
Allow-Events
Authorization
Call-ID
Call-Info
Contact
Content-Length
Content-Type
CSeq
Diversion
History-Info
Event
Expires
From
Max-Forwards
Min-SE
P-Asserted-Identity
P-Preferred-Identity
Proxy-Authenticate
Proxy-Authorization
RAck
Record-Route
Refer-To
Referred-By
Remote-Party-ID
Replaces
Require
Route
RSeq
Session-Expires
438
Supported
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Notes