SIP 183 Session Progress vs 200 OK
SIP 183 (Session Progress) is a 1xx Provisional response, while 200 (OK) is a 2xx Success response. 183 indicates that used to convey information about the progress of the call that is not otherwise classified. Often carries early media (ringback tones, announcements) via SDP. In contrast, 200 means that the request has succeeded. For INVITE, the call has been answered. For other methods, the action has been completed successfully.
説明
Used to convey information about the progress of the call that is not otherwise classified. Often carries early media (ringback tones, announcements) via SDP.
このコードが表示される場合
During call setup, especially in PSTN interworking scenarios. The response may contain SDP for early media like custom ringback tones or IVR prompts.
解決方法
No fix needed — this is informational. If early media is not playing, check codec negotiation and SDP handling in your UA.
説明
The request has succeeded. For INVITE, the call has been answered. For other methods, the action has been completed successfully.
このコードが表示される場合
When a call is answered (INVITE 200 OK), a registration succeeds (REGISTER 200 OK), or a subscription is accepted (SUBSCRIBE 200 OK).
解決方法
No fix needed — this is a success response. The caller should send an ACK to complete the three-way handshake for INVITE transactions.
主な違い
183 is a 1xx Provisional response, while 200 is a 2xx Success response.
SIP 183: Used to convey information about the progress of the call that is not otherwise classified. Often carries early media (ringback tones, announcements) via SDP.
SIP 200: The request has succeeded. For INVITE, the call has been answered. For other methods, the action has been completed successfully.
You encounter 183 when during call setup, especially in PSTN interworking scenarios. The response may contain SDP for early media like custom ringback tones or IVR prompts.
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).
どちらをいつ使うか
For 183 (Session Progress): No fix needed — this is informational. If early media is not playing, check codec negotiation and SDP handling in your UA. 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.