Planet Networking & Communication CS-2001 User Manual page 41


Denotes in which network, i.e. LAN or DMZ, the subnet resides.
VLAN ID

Permits the interface on the CS-2001 to support VLAN tags belonging to the
LAN or DMZ.
Terms in Routing Table
Dynamic Routing

Routers exchange routing information to reflect any changes in the typology of
the network. The convergence of routing information between routers depends
on the size of the network and the protocol.
 RIPv2 (Route Information Protocol) sends out RIPv2 packets to nearby
routers. If a router that supports RIPv2 receives one of these packets, it will
send its routing table back. This provides information to decide the shortest
route to reach a destination.
 Open Shortest Path First (OPSF), gathers link state information from
available routers and constructs a topology map of the network. OSPF
establishes and maintains neighbor relationships in order to exchange
routing updates with other routers. OSPF uses path cost as its basic routing
metric.
 Border Gateway Protocol, is the core routing protocol of the Internet. It
maintains a table of IP networks or 'prefixes' which designate network
reachability among autonomous systems (AS). It is described as a path
vector protocol. BGP does not use traditional Interior Gateway Protocol
(IGP) metrics, but makes routing decisions based on path, network policies
and/or rulesets. BGP was created to replace the Exterior Gateway Protocol
(EGP) routing protocol to allow fully decentralized routing in order to allow
the removal of the NSFNet Internet backbone network.

A unique ASN is allocated to each AS for use in BGP routing. AS
numbers are important because the ASN uniquely identifies each
network on the Internet.
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