Chapter 12 Routing Overview; Routing Overview; Networks And Subnetworks - Juniper J2300 User Manual

Term
topology database
triggered update
virtual link

Routing Overview

Routing is the transmission of data packets from a source to a destination address.
For packets to be correctly forwarded to the appropriate host address, the host
must have a unique numeric identifier or IP address. The unique IP address of
the destination host forms entries in the routing table. These entries are primarily
responsible for determining the path that a packet traverses when transmitted
from source to destination.
This overview includes these topics:

Networks and Subnetworks

Large groups of machines that are interconnected and can communicate with one
another form networks. Typically, networks identify large systems of computers
and devices that are owned or operated by a single entity. Traffic is routed between
or through the networks as data is passed from host to host.
As networks grow large, the ability to maintain the network and effectively
route traffic between hosts within the network becomes increasingly
difficult. To accommodate growth, networks are divided into subnetworks.
Fundamentally, subnetworks behave exactly like networks, except that
they are identified by a more specific network address and subnet mask
Definition
Map of connections between the nodes in a network. The topology database is stored in each
node.
In a network that uses RIP, a routing update that is automatically sent whenever routing
information changes.
In OSPF, a link you create between two area border routers (ABRs) that have an interface to a
common nonbackbone area, to connect a third area to the backbone area. One of the area
border routers must be directly connected to the backbone area.
Networks and Subnetworks on page 259
Autonomous Systems on page 260
Interior and Exterior Gateway Protocols on page 260
Routing Tables on page 260
Forwarding Tables on page 261
Dynamic and Static Routing on page 262
Route Advertisements on page 263
Route Aggregation on page 263
Routing Overview
259
Routing Overview