TEAMFORREST

The Session Initiation Protocol (SIP) is widely used to control VoIP, Video Calls, and other multimedia communication over a newtork. SIP uses design elements similar to HTTP requests/responses (although they are not 1 to 1).

Following is a list of SIP Response Codes:

Information SIP Responses – 1xx

Informational responses, indicate that the server contacted is performing some further action and does not yet have a definitive response. A server sends a 1xx response if it expects to take more than 200 ms to obtain a final response.

• 100 Trying
• 180 Ringing
• 181 Call Is Being Forwarded
• 182 Queued
• 183 Session Progress

Successful SIP Responses – 2xx

The action was successfully received, understood, and accepted.

• 200 OK
• 202 Accepted (request understood, but cannot be processed)

Redirection SIP Responses – 3xx

Further action needs to be taken in order to complete the request.

• 300 Multiple Choices
• 301 Moved Permanently
• 302 Moved Temporarily
• 305 Use Proxy
• 380 Alternative Service

Client Error SIP Responses – 4xx

The request contains bad syntax or cannot be fulfilled at the server.

• 400 Bad Request
• 401 Unauthorized (Used only by registrars or user agents. Proxies will/should use 407)
• 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 (The user is not available here but once was)
• 412 Conditional Request Failed
• 413 Request Entity Too Large
• 414 Request-URI Too Long
• 415 Unsupported Media Type
• 416 Unsupported URI Scheme
• 417 Unknown Resource-Priority
• 420 Bad Extension
• 421 Extension Required
• 422 Session Interval Too Small
• 423 Interval Too Brief
• 424 Bad Location Information
• 428 Use Identity Header
• 429 Provide Referrer Identity
• 433 Anonymity Disallowed
• 436 Bad Identity-Info
• 437 Unsupported Certificate
• 438 Invalid Identity Header
• 480 Temporarily Unavailable
• 481 Call Leg/Transaction Does Not Exist
• 482 Loop Detected
• 483 Too Many Hops
• 484 Address Incomplete
• 485 Ambiguous
• 486 Busy Here
• 487 Request Terminated
• 488 Not Acceptable Here
• 489 Bad Event
• 491 Request Pending
• 493 Undecipherable (Could not decrypt S/MIME body part)
• 494 Security Agreement Required

Server Error SIP Responses – 5xx

The server failed to fulfill an apparently valid request.

• 500 Server Internal Error
• 501 Not Implemented (SIP request method is not implemented at the server)
• 502 Bad Gateway
• 503 Service Unavailable
• 504 Server Time-out
• 505 Version Not Supported (The server does not support the version of the SIP protocol used)
• 513 Message Too Large
• 580 Precondition Failure

Global Failure SIP Responses – 6xx

The request cannot be fulfilled at any server.

• 600 Busy Everywhere
• 603 Decline
• 604 Does Not Exist Anywhere
• 606 Not Acceptable