SIP 183 Session Progress vs 483 Too Many Hops
SIP 183 (Session Progress) is a 1xx Provisional response, while 483 (Too Many Hops) is a 4xx Client Failure 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, 483 means that the Max-Forwards header has reached zero, indicating the request has passed through too many proxies.
คำอธิบาย
Used to convey information about the progress of the call that is not otherwise classified. Often carries early media (ringback tones, announcements) via SDP.
เมื่อคุณพบเห็น
During call setup, especially in PSTN interworking scenarios. The response may contain SDP for early media like custom ringback tones or IVR prompts.
วิธีแก้ไข
No fix needed — this is informational. If early media is not playing, check codec negotiation and SDP handling in your UA.
คำอธิบาย
The Max-Forwards header has reached zero, indicating the request has passed through too many proxies.
เมื่อคุณพบเห็น
When a request traverses more proxies than the Max-Forwards counter allows (default 70). Often indicates a routing loop.
วิธีแก้ไข
Check for routing loops. If the path is legitimately long, increase Max-Forwards. Usually indicates misconfigured routing.
ความแตกต่างหลัก
183 is a 1xx Provisional response, while 483 is a 4xx Client Failure 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 483: The Max-Forwards header has reached zero, indicating the request has passed through too many proxies.
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 483 when when a request traverses more proxies than the Max-Forwards counter allows (default 70). Often indicates a routing loop.
ควรใช้อันไหนเมื่อไร
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 483 (Too Many Hops): Check for routing loops. If the path is legitimately long, increase Max-Forwards. Usually indicates misconfigured routing.