Yealink SIP-T2 SERIES Administrator's Manual page 994

Administrator's Guide for SIP-T2 Series/T19(P) E2/T4 Series/CP860 IP Phones
Method
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
Subscription-State
Supported
To
User-Agent
Via
972
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
Notes