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CHAPTER 2: Introduction
The line level has the following capabilities:
• A/B switching
• Two-, three-, and four-cavity patching
(Refer to Chapter 3, Functions, for descriptions.)
At the Rack level, the line cards are mounted in racks. Each rack has its own
microprocessor-based control card.
The rack level has line bridging and breaking via monitoring bus.
(Refer to Chapter 3, Functions, for descriptions.)
Figure 2-2. Fully Loaded Rack.
At the Site level, each rack control card communicates with a system
management device (for example, a PC).
The site level has the following capabilities:
• group switching
• scheduled switching
• default switching
• alarm monitoring (reporting to system management and selectively to
customer courtesy terminals)
• alarm-triggered switching, with or without fallback