Table of Contents
Advertisement
2.4. PBX Trunk Configurations
The following configurations describe different PBX Trunk configurations
with TE and NT interfaces which you use to connect the PBX to the PSTN and
CGW. The TE interface always receives an independent time clock from the
NT source. A PBX that receives two different source clocks may experience
communication errors, such as the inability to properly disconnect a
completed call.
The following diagrams offer different solutions to handle a double source
clock situation. In each configuration, a person attached to the PBX dials a
number which is first routed to the PBX LCR (Least Cost Route) to verify the
calling prefix, then routed to the correct interface:
• If the prefix is landline, it creates a connection for the call to leave
via the PSTN interface
• If the prefix is cellular, it routes the call to the CGW-I interface and
the CGW-I connects the call through a cellular network operator.
Basic PBX / CGW-I without Synchronization
NT
Source
PSTN
Clock 1
This diagram describes the simplest PBX/CGW-I configuration where the PBX
is able to select only the source clock is receives from the PSTN as the main
clock and adapt the other NT data information it receives from the CGW.
NT1 / CGW-I Synchronization
NT
PSTN
U Point Reference
CGW-I Cellular Gateway BRI-GSM : Installation and Operation Manual
12
11
1
LCR
10
2
9
3
TE
TE
8
4
7
5
6
PBX
NT
TE
NT1
LCR
S Point Reference
PBX
Source
12
11
1
2
10
9
3
Clock
8
4
7
5
6
GSM
Operator 1
SIM 1
NT
Source
12
11
1
10
2
CGW
9
3
Clock 2
8
4
7
5
6
SIM 2
GSM
Operator 1
SIM 1
NT
CGW
TE
SIM 2
Synch-In
GSM
Operator 2
GSM
Operator 2
7
Hide quick links:
Advertisement
Table of Contents
Need help?
Do you have a question about the CGW-I and is the answer not in the manual?
Questions and answers