VoLTE SIP Requests | VoLTE SIP Codes with meaning

This page mentions tables with VoLTE SIP Requests and VoLTE SIP Codes along with descriptions.

VoLTE SIP Requests

Following table-1 mentions VoLTE SIP Requests.


VoLTE SIP Request Description
INVITE client is invited to participate in call session
ACK confirms reception of final response by client for INVITE request
BYE Indicates termination of a call, it is sent either by caller or by called party
CANCEL Indicates cancellation of any pending request
OPTIONS This message queries capabilities of servers.
PRACK Indicates provisional acknowledgement
SUBSCRIBE Indicates subscription to event notification
NOTIFY This message notifies subscriber if there are any new events.
PUBLISH This message publishes event to server.
INFO It carries mid-session information which does not modify session state.
REFER Asks recipient to issue SIP request i.e. call transfer
MESSAGE It transports instant messages using SIP.
UPDATE It modifies state of session without changing the state of dialog.

VoLTE SIP Codes

Following table-2 mentions VoLTE SIP Codes.


VoLTE SIP Code Description
1XX Provisional Responses
100 Trying
180 Ringing
181 call is being forwarded
181 Queued
183 session progress
199 Early dialog terminated
2XX Successful response
200 OK
202 Accepted
204 No notification
3XX Redirection response
300 Multiple choices
301 Moved permanently
302 Moved temporarily
305 Use proxy
380 Alternative service
4XX Client Failure Response
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 Unknown Resource Priority
420 Bad Extension
421 Extension required
422 Session interval too small
423 Interval too brief
428 Use identity Header
429 Provide Referer Identity
430 Flow Failed
433 Anonymity Disallowed
436 Bad Identity Info
437 Unsupported Certificate
438 Invalid Identity Header
439 First Hop Lacks Outbound Support
440 Max Breadth Exceeded
469 Bad Info 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
5XX Server Failure Response
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
6XX Global Failure Response
600 Busy Everywhere
603 Decline
604 Does not exist anywhere
606 Not acceptable


What is difference between

RF and Wireless Terminologies