Cisco Systems RFC 2543 and RFC 3261 Manual De Usuario

100

Trying

Action is being taken on behalf of the 
caller, but the called party is not yet 
located.

Yes

Generates and forwards this 
response for an incoming 
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 
notified of the call.

Yes

Forwards this response.

181

Call is being forwarded

Call is being rerouted to another 
destination.

Yes

182

Queued

Called party is not currently available or 
elects to queue the call rather than reject 
it.

Yes

183

Session  progress

System performs inband alerting for the 
caller.

Yes

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.

300

Multiple choices

Address resolves to more than one 
location. All locations are provided and 
the user or UA can select which location 
to use.

Yes

Does not generate this response. 
If recursive is enabled, recurses 
on all contacts; otherwise 
forwards this response.

301

Moved permanently

User is no longer available at the 
specified location. An alternate location 
is included in the header.

Yes

302

Moved temporarily

User is temporarily unavailable at the 
specified location. An alternate location 
is included in the header.

Yes

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.

305

Use proxy

Caller must use a proxy to contact the 
called party.

Yes

Does not generate this response. 
If recursive is enabled, recurses 
on all contacts; otherwise 
forwards this response.

380

Alternative service

Call is unsuccessful, but alternative 
services are available.

Yes