SSG 500 M Series Hardware Installation and Configuration Guide
18  Front Panel
Dual-Port T1 or E1
The dual-port T1 PIM (shown in Figure 9) and dual-port E1 PIM (shown in 
Figure 10) provide a physical connection to T1 or E1 network media types. Each 
PIM has two physical T1 or E1 ports with an integrated channel service unit (CSU) 
or data service unit (DSU).
Figure 9:  Dual-Port T1 PIM
Figure 10:  Dual-Port E1 PIM
These PIMs provide the following key features:
 Onboard network processor
 Integrated CSU/DSU—eliminates the need for a separate external device
 56-Kbps and 64-Kbps modes
 Independent internal and external clocking system
 Loopback, bit error rate test (BERT), T1 facilities data link (FDL), and long 
buildout diagnostics
T1
STATUS
STATUS
PORT 0
PORT 1
E1
STATUS
STATUS
PORT 0
PORT 1