SIP 200 OK vs 504 Server Time-out
SIP 200 (OK) is a 2xx Success response, while 504 (Server Time-out) is a 5xx Server Failure response. 200 indicates that the request has succeeded. For INVITE, the call has been answered. For other methods, the action has been completed successfully. In contrast, 504 means that the server did not receive a timely response from an external server it accessed while attempting to process the request. Different from 408 (client timeout).
Descrição
The request has succeeded. For INVITE, the call has been answered. For other methods, the action has been completed successfully.
Quando você o vê
When a call is answered (INVITE 200 OK), a registration succeeds (REGISTER 200 OK), or a subscription is accepted (SUBSCRIBE 200 OK).
Como corrigir
No fix needed — this is a success response. The caller should send an ACK to complete the three-way handshake for INVITE transactions.
Descrição
The server did not receive a timely response from an external server it accessed while attempting to process the request. Different from 408 (client timeout).
Quando você o vê
When a proxy's request to a downstream server times out. The proxy itself is working, but the next hop is unresponsive.
Como corrigir
Check the downstream server's availability. Verify DNS resolution for the next-hop domain. Consider adjusting transaction timeout values.
Diferenças principais
200 is a 2xx Success response, while 504 is a 5xx Server Failure response.
SIP 200: The request has succeeded. For INVITE, the call has been answered. For other methods, the action has been completed successfully.
SIP 504: The server did not receive a timely response from an external server it accessed while attempting to process the request. Different from 408 (client timeout).
You encounter 200 when when a call is answered (INVITE 200 OK), a registration succeeds (REGISTER 200 OK), or a subscription is accepted (SUBSCRIBE 200 OK).
You encounter 504 when when a proxy's request to a downstream server times out. The proxy itself is working, but the next hop is unresponsive.
Quando usar qual
For 200 (OK): No fix needed — this is a success response. The caller should send an ACK to complete the three-way handshake for INVITE transactions. For 504 (Server Time-out): Check the downstream server's availability. Verify DNS resolution for the next-hop domain. Consider adjusting transaction timeout values.