SIP Responses
SIP responses generated by the UAS or SIP servers. SIP Response Classes: 1xx - Informational - Indicates the status of call prior to the completion. 2xx - Success - Request has succeeded. 3xx - Redirection - The client should try to complete the request at another server. 4xx - Client Error - The request has failed due to error due to the client. The client may retry. 5xx - Server failure - The request has failed due to server error. request may retry to another server. 6xx - Global failure - the request has failed and can not retry to any server. 1xx --Informational : 100 Trying : This response is used to indicate the next node receives the request and stop the retransmission. This response is sent if there is delay in sending the final response more the 200ms. 180 Ringing: The response is generated if UA receives the INVITE and started the ringing. It may used to initiate local ring back. 181 Call is being Forwarded: This response is indicat...