Page 629

590

Glossary

routing domain

Any collection of end systems and intermediate systems

that operate under an identical set of administrative rules. Every routing
domain contains one or several areas, all individually given a certain area
address.

routing metric

Any value that is used by routing algorithms to determine

whether one route is superior to another. Metrics include such information
as bandwidth, delay, hop count, path cost, load, MTU, reliability, and com-
munication cost. Only the best possible routes are stored in the routing table,
while all other information may be stored in link-state or topological data-
bases. See also: cost.

routing protocol

Any protocol that defines algorithms to be used for

updating routing tables between routers. Examples include IGRP, RIP,
and OSPF.

routing table

A table kept in a router or other internetworking mecha-

nism that maintains a record of only the best possible routes to certain net-
work destinations and the metrics associated with those routes.

1) rendezvous point: A router that acts as the multicast source in a mul-

ticast network. Primarily in a shared tree distribution. 2) Route Processor:
Also known as a supervisory processor, a module on Cisco 7000 series
routers that holds the CPU, system software, and most of the memory com-
ponents used in the router.

RSFC

Route Switch Feature Card: Used to provide routing between

VLANs. The RSFC is a daughter card for the Supervisor engine II G and
Supervisor III G cards. The RSFC is a fully functioning router running the
Cisco IOS.

RSM

Route Switch Module: A route processor that is inserted into the

chassis of a Cisco Catalyst 5000 series switch. The RSM is configured
exactly like an external router.

RSP

Route/Switch Processor: A processor module combining the functions

of RP and SP used in Cisco 7500 series routers. See also: RP and SP.

RTS

Request To Send: An EIA/TIA-232 control signal requesting permis-

sion to transmit data on a communication line.

www.sybex.com