# 電話 SIP 代碼

## 代碼狀態

| 代碼  | 名稱                                      | 描述                                                                                                                                                                                                                                                                                                                                                               |
| --- | --------------------------------------- | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| 100 | Trying                                  | Extended search is being performed so a forking proxy must send a 100 Trying response.                                                                                                                                                                                                                                                                           |
| 180 | Ringing                                 | The Destination User Agent has received the INVITE message and is alerting the user of call.                                                                                                                                                                                                                                                                     |
| 181 | Call Is Being Forwarded                 | Optional, send by Server to indicate a call is being forwarded.                                                                                                                                                                                                                                                                                                  |
| 182 | Queued                                  | Destination was temporarily unavailable, the server has queued the call until the destination is available.                                                                                                                                                                                                                                                      |
| 183 | Session Progress                        | This response may be used to send extra information for a call which is still being set up.                                                                                                                                                                                                                                                                      |
| 199 | Early Dialog Terminated                 | Send by the User Agent Server to indicate that an early dialogue has been terminated.                                                                                                                                                                                                                                                                            |
| 200 | OK                                      | Shows that the request was successful                                                                                                                                                                                                                                                                                                                            |
| 202 | accepted                                | Indicates that the request has been accepted for processing, mainly used for referrals.                                                                                                                                                                                                                                                                          |
| 204 | No Notification                         | Indicates that the request was successful but no response will be received.                                                                                                                                                                                                                                                                                      |
| 300 | Multiple Choices                        | The address resolved to one of several options for the user or client to choose between.                                                                                                                                                                                                                                                                         |
| 301 | Moved Permanently                       | The original Request URI is no longer valid, the new address is given in the Contact header.                                                                                                                                                                                                                                                                     |
| 302 | Moved Temporarily                       | The client should try at the address in the Contact field.                                                                                                                                                                                                                                                                                                       |
| 305 | Use Proxy                               | The Contact field details a proxy that must be used to access the requested destination.                                                                                                                                                                                                                                                                         |
| 380 | Alternative Service                     | The call failed, but alternatives are detailed in the message body.                                                                                                                                                                                                                                                                                              |
| 400 | Bad Request                             | The request could not be understood due to malformed syntax.                                                                                                                                                                                                                                                                                                     |
| 401 | Unauthorized                            | The request requires user authentication. This response is issued by UASs and registrars.                                                                                                                                                                                                                                                                        |
| 402 | Payment Required                        | (Reserved for future use).                                                                                                                                                                                                                                                                                                                                       |
| 403 | Forbidden                               | The server understood the request, but is refusing to fulfil it.                                                                                                                                                                                                                                                                                                 |
| 404 | Not Found                               | The server has definitive information that the user does not exist at the (User not found).                                                                                                                                                                                                                                                                      |
| 405 | Method Not Allowed                      | The method specified in the Request-Line is understood, but not allowed.                                                                                                                                                                                                                                                                                         |
| 406 | Not Acceptable                          | The resource is only capable of generating responses with unacceptable content.                                                                                                                                                                                                                                                                                  |
| 407 | Proxy Authentication Required           | The request requires user authentication.                                                                                                                                                                                                                                                                                                                        |
| 408 | Request Timeout                         | Couldn’t find the user in time.                                                                                                                                                                                                                                                                                                                                  |
| 409 | Conflict                                | User already registered (deprecated)                                                                                                                                                                                                                                                                                                                             |
| 410 | Gone                                    | The user existed once but is not available here any more.                                                                                                                                                                                                                                                                                                        |
| 411 | Length Required                         | The server will not accept the request without a valid content length (deprecated).                                                                                                                                                                                                                                                                              |
| 412 | Conditional Request Failed              | The given precondition has not been met.                                                                                                                                                                                                                                                                                                                         |
| 413 | Request Entity Too Large                | Request body too large.                                                                                                                                                                                                                                                                                                                                          |
| 414 | Request URI Too Long                    | Server refuses to service the request, the Req-URI is longer than the server can interpret.                                                                                                                                                                                                                                                                      |
| 415 | Unsupported Media Type                  | Request body is in a non-supported format.                                                                                                                                                                                                                                                                                                                       |
| 416 | Unsupported URI Scheme                  | Request-URI is unknown to the server.                                                                                                                                                                                                                                                                                                                            |
| 417 | Uknown Resource-Priority                | There was a resource-priority option tag, but no Resource-Priority header.                                                                                                                                                                                                                                                                                       |
| 420 | Bad Extension                           | Bad SIP Protocol Extension used, not understood by the server.                                                                                                                                                                                                                                                                                                   |
| 421 | Extension Required                      | The server needs a specific extension not listed in the Supported header.                                                                                                                                                                                                                                                                                        |
| 422 | Session Interval Too Small              | The request contains a Session-Expires header field with a duration below the minimum.                                                                                                                                                                                                                                                                           |
| 423 | Interval Too Brief                      | Expiration time of the resource is too short.                                                                                                                                                                                                                                                                                                                    |
| 424 | Bad Location Information                | The request’s location content was malformed or otherwise unsatisfactory.                                                                                                                                                                                                                                                                                        |
| 428 | Use Identity Header                     | The server policy requires an Identity header, and one has not been provided.                                                                                                                                                                                                                                                                                    |
| 429 | Provide Referrer Identity               | The server did not receive a valid Referred-By token on the request.                                                                                                                                                                                                                                                                                             |
| 430 | Flow Failed                             | A specific flow to a user agent has failed, although other flows may succeed.                                                                                                                                                                                                                                                                                    |
| 433 | Anonymity Disallowed                    | The request has been rejected because it was anonymous.                                                                                                                                                                                                                                                                                                          |
| 436 | Bad Identity Info                       | The request has an Identity-Info header and the   URI scheme contained cannot be de-referenced.                                                                                                                                                                                                                                                                  |
| 437 | Unsupported Certificate                 | The server was unable to validate a certificate for the domain that signed the request.                                                                                                                                                                                                                                                                          |
| 438 | Invalid Identity Header                 | Server obtained a valid certificate used to sign a request, was unable to verify the signature.                                                                                                                                                                                                                                                                  |
| 439 | First Hop Lacks Outbound Support        | The first outbound proxy doesn’t support the “outbound” feature.                                                                                                                                                                                                                                                                                                 |
| 440 | Max-Breadth Exceeded                    | If a SIP proxy determined a response context had insufficient Incoming Max-Breadth to carry out a desired parallel fork, and the proxy is unwilling/unable to compensate by forking serially or sending a redirect, that proxy MUST return a 440 response. A client receiving a 440 response can infer that its request did not reach all possible destinations. |
| 469 | Bad Info Package                        | If a SIP UA receives an INFO request associated with an Info Package that the UA has not indicated willingness to receive, the UA MUST send a 469 response, which contains a Recv-Info header field with Info Packages for which UA is willing to receive INFO requests.                                                                                         |
| 470 | Consent Needed                          | The source of the request did not have the permission of the recipient to make such a request.                                                                                                                                                                                                                                                                   |
| 480 | Temporarily Unavailable                 | Callee currently unavailable.                                                                                                                                                                                                                                                                                                                                    |
| 481 | Call/Transaction Does Not Exist         | Server received a request that does not match any dialogue or transaction.                                                                                                                                                                                                                                                                                       |
| 482 | Loop Detected                           | Server has detected a loop.                                                                                                                                                                                                                                                                                                                                      |
| 483 | Too Many Hops                           | Max-Forwards header has reached the value ‘0’.                                                                                                                                                                                                                                                                                                                   |
| 484 | Address Incomplete                      | Request-URI incomplete.                                                                                                                                                                                                                                                                                                                                          |
| 485 | Ambiguous                               | Request-URI is ambiguous.                                                                                                                                                                                                                                                                                                                                        |
| 486 | Busy Here                               | Callee is busy.                                                                                                                                                                                                                                                                                                                                                  |
| 487 | Request Terminated                      | Request has terminated by bye or cancel.                                                                                                                                                                                                                                                                                                                         |
| 488 | Not Acceptable Here                     | Some aspects of the session description of the Request-URI are not acceptable.                                                                                                                                                                                                                                                                                   |
| 489 | Bad Event                               | The server did not understand an event package specified in an Event header field.                                                                                                                                                                                                                                                                               |
| 491 | Request Pending                         | Server has some pending request from the same dialogue.                                                                                                                                                                                                                                                                                                          |
| 493 | Undecipherable                          | UndecipherableRequest contains an encrypted MIME body, which recipient can not decrypt.                                                                                                                                                                                                                                                                          |
| 494 | Security Agreement Required             | The server has received a request that requires a negotiated security mechanism.                                                                                                                                                                                                                                                                                 |
| 500 | Server Internal Error                   | The server could not fulfill the request due to some unexpected condition.                                                                                                                                                                                                                                                                                       |
| 501 | Not Implemented                         | The SIP request method is not implemented here.                                                                                                                                                                                                                                                                                                                  |
| 502 | Bad Gateway                             | The server, received an invalid response from a downstream server while trying  to fulfill a request.                                                                                                                                                                                                                                                            |
| 503 | Service Unavailable                     | The server is in maintenance or is temporarily overloaded and cannot process the request.                                                                                                                                                                                                                                                                        |
| 504 | Server Time-out                         | The server tried to access another server while trying  to process a request, no timely response.                                                                                                                                                                                                                                                                |
| 505 | Version Not Supported                   | The SIP protocol version in the request is not supported by the server.                                                                                                                                                                                                                                                                                          |
| 513 | Message Too Large                       | The request message length is longer than the server can process.                                                                                                                                                                                                                                                                                                |
| 555 | Push Notification Service Not Supported | The server does not support the push notification serviced specified in the pn-provider SIP URI parameter.                                                                                                                                                                                                                                                       |
| 580 | Precondition Failure                    | The server is unable or unwilling to meet some constraints specified in the offer.                                                                                                                                                                                                                                                                               |
| 600 | Busy Everywhere                         | All possible destinations are busy.                                                                                                                                                                                                                                                                                                                              |
| 603 | Decline                                 | Destination cannot/doen’t wish to participate in the call,  no alternative destinations.                                                                                                                                                                                                                                                                         |
| 604 | Does Not Exist Anywhere                 | The server has authoritative information that the requested user does not exist anywhere.                                                                                                                                                                                                                                                                        |
| 606 | Not Acceptable                          | The user’s agent was contacted successfully but some aspects of the session description were not acceptable.                                                                                                                                                                                                                                                     |
| 607 | Unwanted                                | The called party did not want his call from the calling party. Future attempts from the calling party are likely to be similarly rejected.                                                                                                                                                                                                                       |


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