SIP 204 No Notification vs 436 Bad Identity-Info
SIP 204 (No Notification) is a 2xx Success response, while 436 (Bad Identity-Info) is a 4xx Client Failure response. 204 indicates that the request was successful but the server has decided not to send a NOTIFY for this SUBSCRIBE request. In contrast, 436 means that the Identity-Info header contains a URI that the server cannot dereference to obtain the signing certificate.
Description
The request was successful but the server has decided not to send a NOTIFY for this SUBSCRIBE request.
When You See It
When subscribing to event packages that may not generate immediate notifications, such as dialog or presence packages.
How to Fix
No fix needed. The subscription was accepted but there is no state change to notify about yet.
Description
The Identity-Info header contains a URI that the server cannot dereference to obtain the signing certificate.
When You See It
When the Identity-Info URI in the request points to an unreachable or invalid certificate location.
How to Fix
Ensure the Identity-Info URI is reachable and points to a valid certificate. Check DNS resolution and TLS configuration.
Key Differences
204 is a 2xx Success response, while 436 is a 4xx Client Failure response.
SIP 204: The request was successful but the server has decided not to send a NOTIFY for this SUBSCRIBE request.
SIP 436: The Identity-Info header contains a URI that the server cannot dereference to obtain the signing certificate.
You encounter 204 when when subscribing to event packages that may not generate immediate notifications, such as dialog or presence packages.
You encounter 436 when when the Identity-Info URI in the request points to an unreachable or invalid certificate location.
When to Use Which
For 204 (No Notification): No fix needed. The subscription was accepted but there is no state change to notify about yet. For 436 (Bad Identity-Info): Ensure the Identity-Info URI is reachable and points to a valid certificate. Check DNS resolution and TLS configuration.