All you need to know about IP Phone Systems · Which SIP Status Codes do exist?

Which SIP Status Codes do exist?

The Session Initiation Protocol (SIP) is a widly used protocol for IP-telephony. It manages the data transfer during a call as well as building up and termination of the connection. To do all this management there are several status codes, used by the SIP standard to open, control or close sessions. You can find a list off those codes below to know, how your PBX is communicating.

Scheme of SIP status codes

Basic Information -> 1XY

100 – Trying
180 – Ringing
181 – Call is being forwarded
182 – Queued
183 – Session progress

Success -> 2XY

200 – OK
202 – Accepted
204 – No notification

Redirection -> 3XY

300 – Multiple choices
301 – Moved permanently
302 – Moved temporarily
305 – Use proxy
380 – Alternative service

System Failures -> 4XY

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
410 – Gone
412 – Conditional request failed
413 – Request entity too large
414 – Request URI too long
415 – Unsupported media type
416 – Unsupported URI scheme
417 – Unsupported resource priority
420 – Bad extension
421 – Extension required
422 – Session interval too small
423 – Interval too brief
428 – Use identity header
429 – Provide referrer identity
430 – Flow failed
433 – Anonymity not allowed
436 – Bad identity information
437 – Unsupported certificate
438 – Invalid identity header
439 – First hop lacks outbound support
440 – Maximal breadth exceeded
469 – Bad information package
470 – Consent needed
480 – Temporarily unavailable
481 – Call/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
494 – Security agreement required

Server errors -> 5XY

500 – Server internal error
501 – Not implemented
502 – Bad gateway
503 – Service unavailable
504 – Server time out
505 – Version not supported
513 – Message too large
580 – Precondition failure

Global errors -> 6XY

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


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