SIP 200 OK vs 500 Server Internal Error
SIP 200 (OK) is a 2xx Success response, while 500 (Server Internal Error) 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, 500 means that the server encountered an unexpected condition that prevented it from fulfilling the request.
Description
The request has succeeded. For INVITE, the call has been answered. For other methods, the action has been completed successfully.
When You See It
When a call is answered (INVITE 200 OK), a registration succeeds (REGISTER 200 OK), or a subscription is accepted (SUBSCRIBE 200 OK).
How to Fix
No fix needed — this is a success response. The caller should send an ACK to complete the three-way handshake for INVITE transactions.
Description
The server encountered an unexpected condition that prevented it from fulfilling the request.
When You See It
When the SIP server has an internal error — database failure, unhandled exception, or resource exhaustion.
How to Fix
Check server logs for the specific error. Common causes include database connectivity issues, configuration errors, or memory exhaustion.
Key Differences
200 is a 2xx Success response, while 500 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 500: The server encountered an unexpected condition that prevented it from fulfilling the request.
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 500 when when the SIP server has an internal error — database failure, unhandled exception, or resource exhaustion.
When to Use Which
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 500 (Server Internal Error): Check server logs for the specific error. Common causes include database connectivity issues, configuration errors, or memory exhaustion.