SIP 204 No Notification vs 604 Does Not Exist Anywhere
SIP 204 (No Notification) is a 2xx Success response, while 604 (Does Not Exist Anywhere) is a 6xx Global 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, 604 means that the server has authoritative information that the user indicated in the Request-URI does not exist anywhere. Unlike 404, this is a definitive, global statement.
Descripción
The request was successful but the server has decided not to send a NOTIFY for this SUBSCRIBE request.
Cuándo lo verás
When subscribing to event packages that may not generate immediate notifications, such as dialog or presence packages.
Cómo solucionarlo
No fix needed. The subscription was accepted but there is no state change to notify about yet.
Descripción
The server has authoritative information that the user indicated in the Request-URI does not exist anywhere. Unlike 404, this is a definitive, global statement.
Cuándo lo verás
When the user definitively does not exist on any server in the network. The server has authoritative knowledge, not just local.
Cómo solucionarlo
The user does not exist. Verify the SIP URI or phone number. Unlike 404, retrying on other servers will not help.
Diferencias clave
204 is a 2xx Success response, while 604 is a 6xx Global Failure response.
SIP 204: The request was successful but the server has decided not to send a NOTIFY for this SUBSCRIBE request.
SIP 604: The server has authoritative information that the user indicated in the Request-URI does not exist anywhere. Unlike 404, this is a definitive, global statement.
You encounter 204 when when subscribing to event packages that may not generate immediate notifications, such as dialog or presence packages.
You encounter 604 when when the user definitively does not exist on any server in the network. The server has authoritative knowledge, not just local.
Cuándo usar cada uno
For 204 (No Notification): No fix needed. The subscription was accepted but there is no state change to notify about yet. For 604 (Does Not Exist Anywhere): The user does not exist. Verify the SIP URI or phone number. Unlike 404, retrying on other servers will not help.