SIP 302 Moved Temporarily vs 486 Busy Here
SIP 302 (Moved Temporarily) is a 3xx Redirection response, while 486 (Busy Here) is a 4xx Client Failure response. 302 indicates that the callee has temporarily moved to a different address. The client should retry the request at the Contact address but continue using the original URI for future requests. In contrast, 486 means that the callee's end system was contacted successfully but the callee is currently not willing or able to take additional calls at this end system.
Description
The callee has temporarily moved to a different address. The client should retry the request at the Contact address but continue using the original URI for future requests.
When You See It
When a user is temporarily reachable at a different location, such as when traveling or using a different device.
How to Fix
Redirect the current call to the Contact URI provided, but keep the original URI for future requests.
Description
The callee's end system was contacted successfully but the callee is currently not willing or able to take additional calls at this end system.
When You See It
When the callee is already on a call and does not have call waiting. The user explicitly rejected the call, or all lines are in use.
How to Fix
Wait and try again later. The callee may become available when their current call ends. Consider leaving a voicemail if available.
Key Differences
302 is a 3xx Redirection response, while 486 is a 4xx Client Failure response.
SIP 302: The callee has temporarily moved to a different address. The client should retry the request at the Contact address but continue using the original URI for future requests.
SIP 486: The callee's end system was contacted successfully but the callee is currently not willing or able to take additional calls at this end system.
You encounter 302 when when a user is temporarily reachable at a different location, such as when traveling or using a different device.
You encounter 486 when when the callee is already on a call and does not have call waiting. The user explicitly rejected the call, or all lines are in use.
When to Use Which
For 302 (Moved Temporarily): Redirect the current call to the Contact URI provided, but keep the original URI for future requests. For 486 (Busy Here): Wait and try again later. The callee may become available when their current call ends. Consider leaving a voicemail if available.