Cisco Systems RFC 2543 and RFC 3261 SIP Transport Layer Protocols, Header Field Supported?

Appendix A SIP Compliance

RFC 2543 and RFC 3261

Table A-4	SIP Header Fields
Header Field		Supported?	Header Field	Supported?
Accept		Yes	Organization	Yes
Accept-Encoding		Yes	MIME-Version	Yes
Accept-Language		Yes	Priority	Yes
Alert-Info		Yes	Proxy-Authenticate	Yes
Allow		Yes	Proxy Authorization	Yes
Also		Yes	Proxy-Require	Yes
Authorization		Yes	Record-Route	Yes
Call-ID		Yes	Require	Yes
Call-Info		Yes	Response-Key	Yes
Contact		Yes	Retry-After	Yes
Content-Disposition		Yes	Route	Yes
Content-Encoding		Yes	Server	Yes
Content-Length		Yes	Subject	Yes
Content-Type		Yes	Supported	Yes
Cseq		Yes	Timestamp	Yes
Date		Yes	To	Yes
Encryption1		No	Unsupported	Yes
Error-Info		Yes	User-Agent	Yes
Expires		Yes	Via	Yes
From		Yes	Warning	Yes
In-Reply-To		Yes	WWW-Authenticate	Yes
Max-Forwards		Yes

1. When a SIP message is received that contains this header field, the message is processed with the field ignored.

SIP Transport Layer Protocols

Table A-5	SIP Transport Layer Protocols
Transport Layer Protocol		Supported?
Unicast UDP		Yes
Multicast UDP		No
TCP		Yes
TLS		Yes

Cisco SIP Proxy Server Administrator Guide

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