Lucent Technologies 8.2 User Manual

Page of 1707
DEFINITY ECS Release 8.2
Administrator’s Guide  
555-233-506  
Issue 1
April 2000
Features and technical reference 
1341
Generalized route selection 
20
Detailed description
GRS recognizes one or more Bearer Capability Class (BCC) for each trunk group 
preference in the route pattern. BCC defines the type of information being sent as 
voice or data. The switch checks the BCC for all trunk groups to see if the route 
selected and type of call are compatible. The BCC is assigned to the route 
preference on the Route Pattern screen.
GRS chooses a preference with BCC set to yes in this order: BCC 2, BCC 1, BCC 
3, BCC 4. 
When an exact match is not found in any route-pattern preference, calls with 
originating BCCs listed are treated as follows:
BCC of 0 (such as voice or analog modem)
GRS routes a BCC 0-originated call with no match. This allows voice 
transfer to data when making a data call. 
Since BCC 0 (voice) has no Information Transfer Capability (ITC), the 
switch selects an ITC from the route pattern when a BCC 0 call is routed as 
a data call. 
Table 50
 shows how the ITC codepoint in the Bearer Capability 
IE is determined.
BCC 2
If there is no preference with BCC 2 yes, GRS chooses a preference with 
BCC 0 yes. If BCC 0 yes does not exist, the call is blocked.
BCC 1, 3, or 4
BCC 4 (DCP/DMI Mode 0), BCC 1 (Mode 1), and BCC 3 (Mode 3) calls 
requires an exact match in order for the call to complete. ITCs must also 
match.
Table 50.
Determination of ITC Codepoint
Originating 
Endpoint’s 
ITC
Routing Preference’s ITC
ITC 
codepoint 
in BC IE
restricted
un-
restricted
both 
endpoint
both un-
restricted
voice
x
restricted
voice
x
unrestricted
voice
x
unrestricted
voice
x
unrestricted