SIP 181 Call Is Being Forwarded vs 406 Not Acceptable
SIP 181 (Call Is Being Forwarded) is a 1xx Provisional response, while 406 (Not Acceptable) is a 4xx Client Failure response. 181 indicates that a proxy server may send this to indicate that the call is being forwarded to a different set of destinations. In contrast, 406 means that the resource identified by the request is only capable of generating responses with content characteristics not acceptable according to the Accept header.
Mô tả
A proxy server may send this to indicate that the call is being forwarded to a different set of destinations.
Khi bạn thấy mã này
When the callee has call forwarding enabled and the request is being redirected to another number or device.
Cách khắc phục
No action needed. The call is being redirected. If forwarding is unintended, the callee should update their forwarding settings.
Mô tả
The resource identified by the request is only capable of generating responses with content characteristics not acceptable according to the Accept header.
Khi bạn thấy mã này
When content negotiation fails — the server cannot produce a response matching the Accept header fields in the request.
Cách khắc phục
Review the Accept headers in your request and broaden the acceptable content types.
Sự khác biệt chính
181 is a 1xx Provisional response, while 406 is a 4xx Client Failure response.
SIP 181: A proxy server may send this to indicate that the call is being forwarded to a different set of destinations.
SIP 406: The resource identified by the request is only capable of generating responses with content characteristics not acceptable according to the Accept header.
You encounter 181 when when the callee has call forwarding enabled and the request is being redirected to another number or device.
You encounter 406 when when content negotiation fails — the server cannot produce a response matching the Accept header fields in the request.
Khi nào dùng cái nào
For 181 (Call Is Being Forwarded): No action needed. The call is being redirected. If forwarding is unintended, the callee should update their forwarding settings. For 406 (Not Acceptable): Review the Accept headers in your request and broaden the acceptable content types.