SIP 204 No Notification vs 407 Proxy Authentication Required
SIP 204 (No Notification) is a 2xx Success response, while 407 (Proxy Authentication Required) 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, 407 means that the client must first authenticate with the proxy. The proxy returns a Proxy-Authenticate header with a challenge.
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 client must first authenticate with the proxy. The proxy returns a Proxy-Authenticate header with a challenge.
When You See It
When a SIP proxy requires authentication before forwarding the request. Similar to 401 but for proxy servers.
How to Fix
Resend the request with a Proxy-Authorization header containing valid credentials for the proxy.
Key Differences
204 is a 2xx Success response, while 407 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 407: The client must first authenticate with the proxy. The proxy returns a Proxy-Authenticate header with a challenge.
You encounter 204 when when subscribing to event packages that may not generate immediate notifications, such as dialog or presence packages.
You encounter 407 when when a SIP proxy requires authentication before forwarding the request. Similar to 401 but for proxy servers.
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 407 (Proxy Authentication Required): Resend the request with a Proxy-Authorization header containing valid credentials for the proxy.