Yealink SIP-T2XP Administrator's Manual page 444

Administrator's Guide for SIP-T2xP and SIP-T19P IP Phones
2xx Response
200 OK
202 Accepted
3xx Response—Redirection Responses
3xx Response
300 Multiple Choices
301 Moved Permanently
302 Moved Temporarily
4xx Response—Request Failure Responses
4xx Response
400 Bad Request
401 Unauthorized
402 Payment Required
403 Forbidden
404 Not Found
405 Method Not Allowed
406 Not Acceptable
407 Proxy Authentication
Required
408 Request Timeout
409 Conflict
410 Gone
411 Length Required
413 Request Entity Too Large
414 Request-URI Too Long
415 Unsupported Media Type
416 Unsupported URI Scheme
420 Bad Extension
421 Extension Required
428
Supported
Yes
Yes In REFER transfer.
Supported
Yes
Yes
Yes
Supported
Yes
Yes
Yes
Yes
Yes
Yes
No
Yes
Yes
No
No
No
No
Yes
Yes
No
No
No
Notes
Notes
Notes