Version 6.4 243 March 2012
SIP User's Manual 18. GW and IP to IP
Receiving Reason header: If a call is disconnected from the IP side and the SIP
message includes the Reason header, it is sent to the Tel side according to the
following logic:
• If the Reason header includes a Q.850 cause, it is sent as is.
• If the Reason header includes a SIP response:
♦ If the message is a final response, the response status code is translated to
Q.850 format and passed to ISDN.
♦ If the message isn’t a final response, it is translated to a Q.850 cause.
• When the Reason header is received twice (i.e., SIP Reason and Q.850), the
Q.850 takes precedence over the SIP reason and is sent to the Tel side.
18.1.6.1.2 Fixed Mapping of ISDN Release Reason to SIP Response
The following table describes the mapping of ISDN release reason to SIP response.
Table 18-2: Mapping of ISDN Release Reason to SIP Response
ISDN Release
Reason
Description
SIP
Response
Description
1 Unallocated number 404 Not found
2 No route to network 404 Not found
3 No route to destination 404 Not found
6 Channel unacceptable 406
*
Not acceptable
7
Call awarded and being delivered in an
established channel
500 Server internal error
16 Normal call clearing -* BYE
17 User busy 486 Busy here
18 No user responding 408 Request timeout
19 No answer from the user 480 Temporarily unavailable
21 Call rejected 403 Forbidden
22 Number changed w/o diagnostic 410 Gone
26 Non-selected user clearing 404 Not found
27 Destination out of order 502 Bad gateway
28 Address incomplete 484 Address incomplete
29 Facility rejected 501 Not implemented
30 Response to status enquiry 501* Not implemented
31 Normal unspecified 480 Temporarily unavailable
34 No circuit available 503 Service unavailable
38 Network out of order 503 Service unavailable
41 Temporary failure 503 Service unavailable
42 Switching equipment congestion 503 Service unavailable
43 Access information discarded 502* Bad gateway
44 Requested channel not available 503* Service unavailable
To Next Page
Loading...
