SIP 100 Trying vs 403 Forbidden
SIP 100 (Trying) is a 1xx Provisional response, while 403 (Forbidden) is a 4xx Client Failure response. 100 indicates that the request has been received by the next-hop server and an unspecified action is being taken to process it. The UAC should expect additional responses. 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.
विवरण
The request has been received by the next-hop server and an unspecified action is being taken to process it. The UAC should expect additional responses.
जब आप इसे देखें
Immediately after sending an INVITE. The proxy has received the call and is searching for the callee. This is the SIP equivalent of a dial tone.
कैसे ठीक करें
No fix needed — this is normal call setup behavior. If stuck on 100 Trying for too long, check network connectivity and proxy configuration.
विवरण
The server understood the request but is refusing to fulfill it. Authorization will not help. The request should not be repeated.
जब आप इसे देखें
When the server policy denies the request regardless of credentials. Common for blocked numbers, restricted routes, or ACL violations.
कैसे ठीक करें
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.
मुख्य अंतर
100 is a 1xx Provisional response, while 403 is a 4xx Client Failure response.
SIP 100: The request has been received by the next-hop server and an unspecified action is being taken to process it. The UAC should expect additional responses.
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 100 when immediately after sending an INVITE. The proxy has received the call and is searching for the callee. This is the SIP equivalent of a dial tone.
You encounter 403 when when the server policy denies the request regardless of credentials. Common for blocked numbers, restricted routes, or ACL violations.
कब किसका उपयोग करें
For 100 (Trying): No fix needed — this is normal call setup behavior. If stuck on 100 Trying for too long, check network connectivity and proxy configuration. 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.