Physical Layer Interface Modules - Cisco CRS-1 System Description

Chapter 5 Line Cards, Physical Layer Interface Modules, and Shared Port Adapters Overview

Physical Layer Interface Modules

A physical layer interface module (PLIM) provides the packet interfaces for the routing system. Optic
modules on the PLIM contain ports to which fiber-optic cables are connected. User data is received and
transmitted through the PLIM ports, and converted between the optical signals (used in the network) and
the electrical signals (used by line card chassis components).
Each PLIM is paired with a line card through the chassis midplane. The line card provides Layer 3 services
for the user data, and the PLIM provides Layer 1 and Layer 2 services. A line card can be paired with
different types of PLIMs to provide a variety of packet interfaces and port densities.
In the Cisco CRS 4-Slot Line Card Chassis, line cards and PLIMs are both installed in the front of the
chassis, and mate through the chassis midplane. The chassis midplane enables you to remove and replace
a line card without disconnecting the user cables on the PLIM.
You can mix and match PLIM types in the chassis.
Because invisible radiation may be emitted from the aperture of the port when no fiber cable is
Warning
connected, avoid exposure to radiation and do not stare into open apertures. Statement 125
Warning Class 1 Laser Product. Statement 113
Warning Class 1 LED product. Statement 126
Warning For diverging beams, viewing the laser output with certain optical instruments within a distance of
100 mm may pose an eye hazard. For collimated beams, viewing the laser output with certain optical
instruments designed for use at a distance may pose an eye hazard. Statement 282
Laser radiation. Do not view directly with optical instruments. Class 1M laser product. Statement 283
Warning
Various types of PLIM interfaces are available for the line card chassis. These interfaces are described
in detail, in the following Cisco publications:
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•
OL-10805-10
Cisco CRS Carrier Routing System Packet-over-SONET/SDH Physical Layer Interface Module
Installation Note
Cisco CRS Carrier Routing System Gigabit Ethernet Physical Layer Interface Module Installation
Note
Cisco CRS Carrier Routing System 4-Slot Line Card Chassis System Description
Physical Layer Interface Modules
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