Nortel Networks Water System BCM 1000 User Manual

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Appendix G Market profile attributes
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BCM 4.0 for BCM1000 Installation and Maintenance Guide Addendum
Analog and digital trunk types
 provides a description of the types of analog and digital trunks.
Note that some of the analog and digital trunks are available only when you select specific market 
profiles.
Table 33   Analog and digital trunk types and descriptions (Sheet 1 of 2)
Trunk types
Description
Digital trunk types:
T1/E1
Digital line that carries data on 24 channels at 1.544 Mb/s (North America); 30 channels at 
2,048 Mb/s (Europe)
Loop, E&M, DID, and ground start lines are also versions of T1 lines.
You can program auto-answer T1 loop start, T1 E&M trunks, T1 DID, T1 ground start trunks, 
PRI and IP trunks to map to target lines to provide for attendant bypass (calling directly to a 
department or individual) and line concentration (one trunk can map onto several target 
lines).
DID
A type of T1 trunk line that allows an outside caller to dial directly into a line on the BCM 
system.
Loop
A type of T1 line that is used on systems where the service provider supports disconnect 
supervision for the digital loop start trunks.
These trunks provide remote access to the BCM system from the public network. These 
trunks must have disconnect supervision to allow the trunk to be set to auto-answer, which 
provides the remote access portal.
Ground
T1-groundstart trunk.
These lines offer the same features as loop start trunks, but are used when the local service 
provider does not support disconnect supervision for digital loop start trunks. Ground start 
trunks work with T1 only. By configuring lines as ground start, the system recognizes when a 
call is released at the far end.
E&M
T1 and E&M. This type of trunk line is used to create simple network connections to other 
phone systems.
This trunk always operates in a disconnected supervised mode.
PRI
ISDN interface with 23 B channels and 1 D channel at 1.544 Mb/s (in Europe: 30 B-channels 
and 1 D-channels at 2.048 Mb/s).
These lines give you incoming and outgoing access to an ISDN network and are 
auto-answer trunks.
BRI
ISDN loop that provides both T and S reference point loops.
These loops can support both network (T and S loops) and terminal equipment (S-Loop) 
connections.
This type of line provides incoming and outgoing access to an ISDN network. ETSI ISDN 
BRI is the European Telecommunications Standards Institute specification for BRI ISDN 
service. BRI provides two bearer B-channels operating at 64 Kb/s and a data D-channel 
which operates at 16 Kb/s. The D-channel is used primarily to carry call information. Like 
loop start trunks, BRI lines can be configured as manual-answer or auto-answer. 
DASS2
(British) Trunk provides multiline IDA interconnection to the British Telecom network.