Avaya Definity SI, Maintenance Manual, Page: 171 / 2968

Install DS1 CPE Loopback Jack (T1 Only)
Issue 4 May 2002 5-67 555-233-123
Configurations Without a Smart Jack
When the loopback jack is added to a span that does not contain a Smart Jack,
the span is divided into 2 sections. See
Figure 5-14 on page 5-67 and Figure 5-15
on page 5-68 .
1. ICSU to the loopback jack.
2. Loopback jack to the Central Office (CO).
Figure 5-14. Network Interface at “Dumb” Block
Figure Notes:
1. Span Section 1
2. Span Section 2
3. 120A2 (or later) Integrated
Channel Service Unit
(ICSU)
4. RJ-48 to Network Interface
(Up to 1000 Feet) (305 m)
5. Loopback Jack
6. “Dumb” Block (Demarcation Point)
7. Interface Termination or Fiber MUX
8. Central Office