SIP 182 Queued vs 482 Loop Detected
SIP 182 (Queued) is a 1xx Provisional response, while 482 (Loop Detected) is a 4xx Client Failure response. 182 indicates that the called party is temporarily unavailable but the server has decided to queue the call rather than reject it. The call will be attempted when the callee becomes available. In contrast, 482 means that the server has detected a loop. The request was received with its own address in the Via header, indicating it has been forwarded back to itself.
Description
The called party is temporarily unavailable but the server has decided to queue the call rather than reject it. The call will be attempted when the callee becomes available.
When You See It
In call center or queuing scenarios where the callee is busy but the system holds the call in a queue.
How to Fix
Wait for the call to be dequeued. If queuing is not desired, configure the server to reject calls instead of queuing them.
Description
The server has detected a loop. The request was received with its own address in the Via header, indicating it has been forwarded back to itself.
When You See It
When routing configuration causes a request to cycle between two or more proxies without reaching the callee.
How to Fix
Review proxy routing tables and DNS records. Check for circular references in SIP routing. Fix the routing configuration to break the loop.
Key Differences
182 is a 1xx Provisional response, while 482 is a 4xx Client Failure response.
SIP 182: The called party is temporarily unavailable but the server has decided to queue the call rather than reject it. The call will be attempted when the callee becomes available.
SIP 482: The server has detected a loop. The request was received with its own address in the Via header, indicating it has been forwarded back to itself.
You encounter 182 when in call center or queuing scenarios where the callee is busy but the system holds the call in a queue.
You encounter 482 when when routing configuration causes a request to cycle between two or more proxies without reaching the callee.
When to Use Which
For 182 (Queued): Wait for the call to be dequeued. If queuing is not desired, configure the server to reject calls instead of queuing them. For 482 (Loop Detected): Review proxy routing tables and DNS records. Check for circular references in SIP routing. Fix the routing configuration to break the loop.