
Appendix A SIP Compliance
RFC 2543 and RFC 3261
•5xx 
•6xx 
Table   | SIP Responses  | 
SIP Response
Meaning
Supported?
Cisco SPS Action
1xx   | 
  | 
  | ||
  | 
  | 
  | 
  | 
  | 
100  | Trying  | Action is being taken on behalf of the  | Yes  | Generates and forwards this  | 
  | 
  | caller, but the called party is not yet  | 
  | response for an incoming  | 
  | 
  | located.  | 
  | INVITE. Upon receiving this  | 
  | 
  | 
  | 
  | response, waits for a 180  | 
  | 
  | 
  | 
  | Ringing, 183 Session progress,  | 
  | 
  | 
  | 
  | or 200 OK response.  | 
  | 
  | 
  | 
  | 
  | 
180  | Ringing  | Called party is located and is being  | Yes  | Forwards this response.  | 
  | 
  | notified of the call.  | 
  | 
  | 
  | 
  | 
  | 
  | 
  | 
181  | Call is being forwarded  | Call is being rerouted to another  | Yes  | 
  | 
  | 
  | destination.  | 
  | 
  | 
  | 
  | 
  | 
  | 
  | 
182  | Queued  | Called party is not currently available or  | Yes  | 
  | 
  | 
  | elects to queue the call rather than reject  | 
  | 
  | 
  | 
  | it.  | 
  | 
  | 
  | 
  | 
  | 
  | 
  | 
183  | Session progress  | System performs inband alerting for the  | Yes  | 
  | 
  | 
  | caller.  | 
  | 
  | 
  | 
  | 
  | 
  | 
  | 
2xx 
200 OK
Request has been successfully processed. The action taken depends on the request made.
Yes
Generates this response to a REGISTER or CANCEL request. Otherwise forwards this response.
3xx 
300  | Multiple choices  | Address resolves to more than one  | Yes  | 
  | 
  | location. All locations are provided and  | 
  | 
  | 
  | the user or UA can select which location  | 
  | 
  | 
  | to use.  | 
  | 
  | 
  | 
  | 
  | 
301  | Moved permanently  | User is no longer available at the  | Yes  | 
  | 
  | specified location. An alternate location  | 
  | 
  | 
  | is included in the header.  | 
  | 
  | 
  | 
  | 
  | 
302  | Moved temporarily  | User is temporarily unavailable at the  | Yes  | 
  | 
  | specified location. An alternate location  | 
  | 
  | 
  | is included in the header.  | 
  | 
  | 
  | 
  | 
  | 
305  | Use proxy  | Caller must use a proxy to contact the  | Yes  | 
  | 
  | called party.  | 
  | 
  | 
  | 
  | 
  | 
380  | Alternative service  | Call is unsuccessful, but alternative  | Yes  | 
  | 
  | services are available.  | 
  | 
  | 
  | 
  | 
  | 
Does not generate this response. If recursive is enabled, recurses on all contacts; otherwise forwards this response.
In redirect mode, generates this response when it locates one or more contacts. In proxy mode, if recursive is enabled, recurses on all contacts; otherwise forwards this response.
Does not generate this response. If recursive is enabled, recurses on all contacts; otherwise forwards this response.
Cisco SIP Proxy Server Administrator Guide