Cisco Systems Cisco CRS-1

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Cisco CRS-1 Carrier Routing System 4-Slot Line Card Chassis Installation Guide

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Chapter 1 Overview

Chassis Components

Figure 1-2 Rear (SFC) View of the Cisco CRS-1 4-Slot Line Card Chassis

The Cisco CRS-1 4-slot line card chassis contains the following compone nts:

• As many as four modular services cards (MSCs, also called line cards) and four physical layer

interface modules (PLIMs). The MSC and PLIM are an associated pair of cards that mate through

the chassis midplane. The MSC provides the forwarding engine for Layer 3 routing of user data, and

the PLIM provides the physical interface and connectors for the user data.

An MSC can be associated with several different PLIMs that provide different interface speeds and

technologies. For a full list of available PLIMs, please contact your Cisco sales representative.

• A chassis midplane that connects MSCs to their associated PLIMs. The midplane design allows an

MSC to be removed from the chassis without having to disconnect the cables that are attached to the

associated PLIM. The midplane distributes power, connects the MSCs to the switch fabric cards, and

provides control plane interconnections. The midplane is not field replaceable by the cust omer.

1Fan tray 3Switch fabric card slots

2AC power plug connectors

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