Glossary
Glossary-30 PortMa ster Configuration Guide
route reflection
In BGP, a method for maintaining path and attribute information across an autonomous
system, while avoiding the overhead of having all peers within an autonomous system
fully communicate to—be fully meshed with—each other. To reduce the number of links,
all internal peers are divided into clusters, each of which has one or more route reflectors.
A route received by a route reflector from an internal peer is transmitted to its clients ,
which are the other peers in the cluster that are not route reflectors. Route reflection
requires that all internal peers use identical policies.
Confederations are another way to avoid configuring a fully meshed set of peers in a
single autonomous system. In contrast to route reflection clusters, confederations require
all routers in the autonomous system to operate as confederation members. However,
confederations provide a finer control of routing within the autonomous system by
allowing for policy changes across confederation boundaries. See also cluster ; cluster
ID; confederation; route reflector.
route reflector
A router configured to transmit routes received from internal BGP peers to one or mo re
other internal peers within its same cluster. These peers are called the route reflector’s
clients. See also cluster; cluster ID; route reflection.
router ID
One of the interface addresses configured on a BGP speaker. The router ID is chosen as
the address that uniquely identifies the BGP speaker on the Internet.
Routing Information Protocol
See RIP.
routing table
A database of routes to particular network destinations, stored on a router or other
device. The routing table stored on the PortMaster contains the follo wing information for
each route: IP address and netmask length of the destination, IP address of the gateway,
source of the route (if any), type of route, hop-count metric, a nd PortMaster interface
used to forward packets along the route.
RS-232 interface
A standard for data communication using serial data and control signals.
runt packet
A packet with a frame size between 8 and 63 bytes with frame check sequence (FCS) or
alignment errors. The runt packet is presumed to be a fragment resulting from a collision.