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CHAPTER 4: Components
Figure 4-5. Switch/Patch Card.
4.4 Rear Cards
Rear cards work with front cards to manage lines. The front card contains the
switching and patching circuitry; the rear card contains the cable interface
circuitry. The front card and the rear card mate when they are inserted into a rack.
Rear cards and front cards that mate must be compatible. See the description of
the front card (Section 4.3) for a list of the compatible rear cards.
In a rack, there are 16 slots for front cards, and 16 corresponding slots for rear
cards. The cards occupy one slot.
Rear cards have ports that correspond with their applications. They also have a
slot number window that indicates the number of the slot in which the card is
installed.