SIP 204 No Notification vs 305 Use Proxy
SIP 204 (No Notification) is a 2xx Success response, while 305 (Use Proxy) is a 3xx Redirection response. 204 indicates that the request was successful but the server has decided not to send a NOTIFY for this SUBSCRIBE request. In contrast, 305 means that the requested resource must be accessed through the proxy given by the Contact header field.
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 requested resource must be accessed through the proxy given by the Contact header field.
When You See It
When the request must be routed through a specific outbound proxy server.
How to Fix
Resend the request through the proxy specified in the Contact header of this response.
Key Differences
204 is a 2xx Success response, while 305 is a 3xx Redirection response.
SIP 204: The request was successful but the server has decided not to send a NOTIFY for this SUBSCRIBE request.
SIP 305: The requested resource must be accessed through the proxy given by the Contact header field.
You encounter 204 when when subscribing to event packages that may not generate immediate notifications, such as dialog or presence packages.
You encounter 305 when when the request must be routed through a specific outbound proxy server.
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 305 (Use Proxy): Resend the request through the proxy specified in the Contact header of this response.