SIP 204 No Notification vs 433 Anonymity Disallowed
SIP 204 (No Notification) is a 2xx Success response, while 433 (Anonymity Disallowed) 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, 433 means that the request has been rejected because the server policy requires caller identification and the request was anonymous.
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 request has been rejected because the server policy requires caller identification and the request was anonymous.
When You See It
When calling with caller ID suppressed (anonymous) to a server or destination that requires caller identification.
How to Fix
Remove the Privacy header or include proper caller identification. Some networks require valid From header identity.
Key Differences
204 is a 2xx Success response, while 433 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 433: The request has been rejected because the server policy requires caller identification and the request was anonymous.
You encounter 204 when when subscribing to event packages that may not generate immediate notifications, such as dialog or presence packages.
You encounter 433 when when calling with caller ID suppressed (anonymous) to a server or destination that requires caller identification.
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 433 (Anonymity Disallowed): Remove the Privacy header or include proper caller identification. Some networks require valid From header identity.