SIP 181 Call Is Being Forwarded vs 493 Undecipherable
SIP 181 (Call Is Being Forwarded) is a 1xx Provisional response, while 493 (Undecipherable) 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, 493 means that the request body was encrypted with S/MIME but the server cannot decrypt it. The server may lack the necessary key or certificate.
描述
A proxy server may send this to indicate that the call is being forwarded to a different set of destinations.
何时出现
When the callee has call forwarding enabled and the request is being redirected to another number or device.
如何修复
No action needed. The call is being redirected. If forwarding is unintended, the callee should update their forwarding settings.
描述
The request body was encrypted with S/MIME but the server cannot decrypt it. The server may lack the necessary key or certificate.
何时出现
When using S/MIME encryption for SIP message bodies and the recipient does not have the corresponding decryption key.
如何修复
Ensure the recipient has the correct S/MIME certificate and private key. Consider using TLS for transport-layer encryption instead.
主要区别
181 is a 1xx Provisional response, while 493 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 493: The request body was encrypted with S/MIME but the server cannot decrypt it. The server may lack the necessary key or certificate.
You encounter 181 when when the callee has call forwarding enabled and the request is being redirected to another number or device.
You encounter 493 when when using S/MIME encryption for SIP message bodies and the recipient does not have the corresponding decryption key.
何时使用哪个
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 493 (Undecipherable): Ensure the recipient has the correct S/MIME certificate and private key. Consider using TLS for transport-layer encryption instead.