SIP 204 No Notification vs 403 Forbidden
SIP 204 (No Notification) is a 2xx Success response, while 403 (Forbidden) 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, 403 means that the server understood the request but is refusing to fulfill it. Authorization will not help. The request should not be repeated.
説明
The request was successful but the server has decided not to send a NOTIFY for this SUBSCRIBE request.
このコードが表示される場合
When subscribing to event packages that may not generate immediate notifications, such as dialog or presence packages.
解決方法
No fix needed. The subscription was accepted but there is no state change to notify about yet.
説明
The server understood the request but is refusing to fulfill it. Authorization will not help. The request should not be repeated.
このコードが表示される場合
When the server policy denies the request regardless of credentials. Common for blocked numbers, restricted routes, or ACL violations.
解決方法
Check server ACLs and routing policies. Verify the caller is permitted to make this type of call. Contact the server administrator if the block is unexpected.
主な違い
204 is a 2xx Success response, while 403 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 403: The server understood the request but is refusing to fulfill it. Authorization will not help. The request should not be repeated.
You encounter 204 when when subscribing to event packages that may not generate immediate notifications, such as dialog or presence packages.
You encounter 403 when when the server policy denies the request regardless of credentials. Common for blocked numbers, restricted routes, or ACL violations.
どちらをいつ使うか
For 204 (No Notification): No fix needed. The subscription was accepted but there is no state change to notify about yet. For 403 (Forbidden): Check server ACLs and routing policies. Verify the caller is permitted to make this type of call. Contact the server administrator if the block is unexpected.