BCSM Detection Points 50 and 51

Till Camel Phase 4, the O_Not_Reachable and T_Not_Reachable conditons were only able to armed using O_Busy and T_Busy events. In this case, in order to differentiate the Not Rechable condition from the Busy conditions we have to relay on the Release Causes in the ISUP Messages. When ISUP Release Cause 17 identifies the Busy condition, 20 will be used to identify the Not Rechable / Subscriber Not Present condition.

In Camel Phase 4, the Not Rechable conditions can be armed using detection points 50 for originationg and 51 for terminating calls.

O-BCSM Detection Points:

1	Origination_Attempt_Authorized
2	Collected_Info
3	Analyzed_Info
4	Route_Select_Failure
5	O_Called_Party_Busy
6	O_No_Answer
7	O_Answer
8	O_Mid_Call
9	O_Disconnect
10	O_Abandon
50	O_Not_Rechable

T-BCSM Detection Points:

12	Termination_Attempt_Authorized
13	T_Called_Party_Busy
14	T_No_Answer
15	T_Answer
16	T_Mid_Call
17	T_Disconnect
18	T_Abandon
51	T_Not_Rechable

ISUP Release Causes:

Rel Cause Value	ITU-T Description
1	Unallocated (unassigned) number
3	No route to destination
5	Misdialled trunk prefix (national use)
16	Normal call clearing
17	User busy
18	No user responding
19	No answer from user (user alerted)
20	Subscriber absent
21	Call rejected
22	Number changed
27	Destination out of order
28	Invalid number format (address incomplete)
31	Normal, unspecified
34	No circuit/channel available
38	Network out of order
41	Temporary failure
42	Switching equipment congestion
44	Requested circuit/channel not available
47	Resource unavailable, unspecified
50	Requested facility not subscribed
57	Bearer capability not authorized
63	Service or option not available, unspecified
65	Bearer capability not implemented
69	Requested facility not implemented
88	Incompatible destination
95	Invalid message, unspecified
102	Recovery on timer expiry
111	Protocol error, unspecified
127	Interworking, unspecified