Troubleshooting and Repair
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T1 Trunk (D4 DS-1)
A T1 Trunk is a digital trunking standard that supports multiple users.
Unlike analog trunks, the T-1 hardware signaling layer is independent
of trunk usage; synchronization & signaling are dealt with separately.
Synchronization
The T1 trunk establishes and maintains a connection between the
two systems. Sampling clocks of each partner must be
synchronized.
n
The Master-Slave arrangement defines the leader and follower;
if connecting to a Public Network T1, the PBX will always be a
slave.
n
The stratum clock levels define the accuracy of the clock and the
ability to match with the incoming master clock signal.The higher
stratum number synchronizes to the same or lower stratum
number. For example, a Stratum 4 (PBX) clock synchronizes to
a Stratum 3 (CO/PBX/Channel Service Unit) clock.
n
When the PBX is connecting to more than one T-1 signal,
choose the order of preference of clocking sources in CDE Form
Figure 18: T1 Trunk Synchronization
Summary of Contents for SX-200 EL
Page 1: ...TECHNICIAN S HANDBOOK LIGHTWARE 19 RELEASE 3 0 ...
Page 11: ...Chapter 1 Introduction ...
Page 12: ......
Page 32: ...Technician s Handbook 22 ...
Page 33: ...Chapter 2 Routine Maintenance ...
Page 34: ......
Page 55: ...Chapter 3 Troubleshooting and Repair ...
Page 56: ...Technician s Handbook 46 ...
Page 88: ...Technician s Handbook 78 Figure 16 E M Trunk Type I 2 wire ...
Page 110: ...Technician s Handbook 100 ...
Page 111: ...Chapter 4 Programming ...
Page 112: ......
Page 168: ...Technician s Handbook 158 ...
Page 169: ...Chapter 5 Installation ...
Page 170: ......
Page 239: ...Chapter 6 Maintenance Commands ...
Page 240: ......
Page 258: ...Technician s Handbook 248 ...
Page 261: ...Notes ...
Page 262: ...Technician s Handbook Notes ...