SIP 100 Trying vs 485 Ambiguous
SIP 100 (Trying) is a 1xx Provisional response, while 485 (Ambiguous) 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, 485 means that the Request-URI was ambiguous. The response body may contain a list of possible unambiguous addresses.
คำอธิบาย
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.
เมื่อคุณพบเห็น
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.
วิธีแก้ไข
No fix needed — this is normal call setup behavior. If stuck on 100 Trying for too long, check network connectivity and proxy configuration.
คำอธิบาย
The Request-URI was ambiguous. The response body may contain a list of possible unambiguous addresses.
เมื่อคุณพบเห็น
When the destination address matches multiple users and the server cannot determine which one is intended.
วิธีแก้ไข
Use a more specific SIP URI. Check the response body for a list of possible matches and select the correct one.
ความแตกต่างหลัก
100 is a 1xx Provisional response, while 485 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 485: The Request-URI was ambiguous. The response body may contain a list of possible unambiguous addresses.
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 485 when when the destination address matches multiple users and the server cannot determine which one is intended.
ควรใช้อันไหนเมื่อไร
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 485 (Ambiguous): Use a more specific SIP URI. Check the response body for a list of possible matches and select the correct one.