Cisco Cisco XR 12000 12000 1-Port OC-48c STM-16c POS SDH ISE Line Card

Attach the line card cable-management bracket to the line card as follows:

Position the cable-management bracket over the front of the line card faceplate.

Insert and tighten the captive screw(s) to secure the bracket to the line card.

Starting with the bottom port on the line card, connect each interface cable to the intended port.

For multiport line card cable-management brackets, carefully wrap the cables with the supplied Velcro 
strap. (See 

Figure 39

.) 

For single-port line card cable-management brackets, carefully press the interface cable onto the cable 
clip. (See 

Figure 40

.) Avoid any kinks or sharp bends in the cable. 

 

For information on disconnecting and connecting interface cables, see the 

.

The following sections provide informaton about specifications and cabling for POS line cards:

POS is a high-speed method of transporting Internet Protocol (IP) traffic between two points. This 
technology combines the Point-to-Point Protocol (PPP) with Synchronous Optical Network (SONET) 
and Synchronous Digital Hierarchy (SDH) interfaces.

PPP was designed as a standard method of communicating over point-to-point links. Initial deployment 
was over short local lines, leased lines, and plain-old-telephone-service (POTS) (also called basic 
telephone service) for users of modems. As new packet services and higher speed lines are introduced, 
PPP can be deployed easily in these environments as well. 

SONET is an octet-synchronous multiplex scheme defined by the American National Standards Institute 
(ANSI) standard (T1.1051988) for optical digital transmission at hierarchical rates from 51.840 Mbps 
to 2.5 Gbps (Synchronous Transport Signal, STS-1 to STS-48) and greater. SDH is an equivalent 
international standard for optical digital transmission at hierarchical rates from 155.520 Mbps (STM-1) 
to 2.5 gigabits per second (Gbps) (STM-16) and greater. SONET electrical specifications have been 
defined for single-mode fiber, multimode fiber, and CATV 75-ohm coaxial cable. (For example, the 
4-port OC-3c/STM-1c POS line card allows transmission over single-mode and multimode optical fiber 
at Optical Carrier 3 [OC-3] rates. OC-3 is the Optical Carrier 3 specification for SONET STS-3c and 
SDH STM-1 transmission rates.)

SONET/SDH transmission rates are integral multiples of 51.840 Mbps. The following transmission 
multiples are currently specified and commonly used:

OC-3c/STM-1c—155.520 Mbps 

OC-12c/STM-4c—622.080 Mbps