SIP 100 Trying vs 437 Unsupported Certificate
SIP 100 (Trying) is a 1xx Provisional response, while 437 (Unsupported Certificate) is a 4xx Client Failure response. 100 indicates that the request has been received by the next-hop server and an unspecified action is being taken to process it. The UAC should expect additional responses. In contrast, 437 means that the server was unable to validate the certificate referenced by the Identity-Info header. The certificate may be self-signed or from an untrusted CA.
Description
The request has been received by the next-hop server and an unspecified action is being taken to process it. The UAC should expect additional responses.
Quand vous le voyez
Immediately after sending an INVITE. The proxy has received the call and is searching for the callee. This is the SIP equivalent of a dial tone.
Comment résoudre
No fix needed — this is normal call setup behavior. If stuck on 100 Trying for too long, check network connectivity and proxy configuration.
Description
The server was unable to validate the certificate referenced by the Identity-Info header. The certificate may be self-signed or from an untrusted CA.
Quand vous le voyez
When the signing certificate for SIP Identity validation is not trusted by the verifying server.
Comment résoudre
Use a certificate from a trusted Certificate Authority. Ensure the certificate chain is complete and not expired.
Différences clés
100 is a 1xx Provisional response, while 437 is a 4xx Client Failure response.
SIP 100: The request has been received by the next-hop server and an unspecified action is being taken to process it. The UAC should expect additional responses.
SIP 437: The server was unable to validate the certificate referenced by the Identity-Info header. The certificate may be self-signed or from an untrusted CA.
You encounter 100 when immediately after sending an INVITE. The proxy has received the call and is searching for the callee. This is the SIP equivalent of a dial tone.
You encounter 437 when when the signing certificate for SIP Identity validation is not trusted by the verifying server.
Quand utiliser lequel
For 100 (Trying): No fix needed — this is normal call setup behavior. If stuck on 100 Trying for too long, check network connectivity and proxy configuration. For 437 (Unsupported Certificate): Use a certificate from a trusted Certificate Authority. Ensure the certificate chain is complete and not expired.