Specifications

Section 360-381-202
6
Figure 3 shows a similar application, except the DS1 facility is fractional “T1”. The 360-80 ICB maps the physical
slots into the first eight timeslots of the DS1 and places “all ones” in the remaining timeslots.
3.2 Additional Applications with Optional Secondary T1 Card
When equipped with a secondary T1 unit (ST1U) in addition to the T1-S, three additional applications/configura-
tions are available. They are:
 Dual T1
 Protection
 Drop and Re-Insert
For additional information, see the documentation on the Secondary T1 unit.
3.2.1. Dual T1 Mode
The Dual T1 mode allows the T1 of the T1-S and the T1 of the ST1U to be connected to two different 360-80
ICBs. These two T1s run independently of each other and allow the 360-80 system to provide up to 1.5 Mbps to
each T1 for a total of over 3 Mbps of bandwidth. See Figure 4 for a typical configuration.
Primary
360-80 (A)
360-80 (B)
360-80 (C)
T1-S
ST1U
T1
Secondary
T1
Figure 4. Independent Dual T1 Mode
3.2.2. Protection Mode
The Protection mode allows the T1 of the T1-S and the T1 of the ST1U to be connected to a remote 360-80. The
Primary T1 from the T1-S is used as the transport between the two 360-80s. If the Primary T1 error rate exceeds
a threshold, the system will switch to the T1 from the ST1U (the Secondary T1) as the transport until the Primary
T1 error rate improves. See Figure 5 for a typical configuration.
360-80
Primary
T1
360-80
T1
Protection
T1-S
ST1U
T1-S
ST1U
Figure 5. T1 Protection Application
3.2.3. Drop and Re-Insert Mode
Drop and Re-insert mode allows the primary T1 from the T1-S to be connected to a channel bank toward the net-
work (west) and the secondary T1 from the ST1U to be connected to a channel bank toward a remote location