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Glossary
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router on a stick
A term that identifies a single router interface connected
to a single Distribution-layer switch port. The router is an external router
that provides trunking protocol capabilities for routing between multiple
VLANs. See also: RSM, MSFC.
routing
The process of forwarding logically addressed packets from their
local subnetwork toward their ultimate destination. In large networks, the
numerous intermediary destinations a packet might travel before reaching its
destination can make routing very complex.
routing by rumor
Term used by a distance-vector protocol to explain
how neighbor routers learn about remote networks.
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.
RP
1) rendezvous point: A router that acts as the multicast source in a
multicast network. Primarily in a shared tree distribution. 2) Route Pro-
cessor: Also known as a supervisory processor, a module on Cisco 7000
series routers that holds the CPU, system software, and most of the memory
components used in the router.
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