Cisco Gigabit Switch Router 12008 Installation And Configuration Manual page 77

Overview of the Cisco 12008
These cards provide the interfaces to the router's external physical media. They exchange
packet data with each other by way of the router's switch fabric.
Any unoccupied slot in the upper card cage must have a blank filler panel
Caution
installed for EMI compliance and to ensure proper air flow through the router enclosure.
A vertical cable-management bracket attached to the faceplate of each line card enables you
to neatly arrange the network interface cables for connection to the individual ports on the
line card. The cable-management system is described in detail in the section entitled
"Cable-Management System" on page 8.
The online insertion and removal (OIR) capability of the Cisco 12008 enables you to
remove and replace a line card while the system remains powered up and operational.
The Cisco 12000 series line cards available for use with the Cisco 12008 router are
described briefly in the following sections.
Quad OC-3c/STM-1c POS Line Card
The Quad OC-3c/STM-1c POS line card provides the Cisco 12008 router with four
independent Packet-Over-SONET (POS) ports on a single card. The card interfaces with
the router's switch fabric and provides four OC-3c/STM-1c SC-duplex SONET
connections. These connections are concatenated, which provides for increased efficiency
by eliminating the need to partition the bandwidth.
Figure 1-16 shows a high-level block diagram of the Quad OC-3c/STM-1c POS line card;
Figure 1-17 shows a front view of the card.
Product Overview 1-55