Muhammad Farooq 15-NTU-1084
We can cover following contents:
v What is router.
v System and hardware router
v Routing Table
v Router internal component
v Types of Router
v Interface of Router
v Static and Dynamic and Default Router
v Router Protocol
v Autonomous systems:
v Classes of router protocol
v Advantages and Disadvantages
v Router can connect two or more
network for communication.
v Routing is the process that a router uses to
forward packets toward the destination network.
v A router makes decisions based
upon the destination IP address of a packet.
v In order to make the correct
decisions, routers must learn the direction to remote networks.
v Router is called computer but it
is design to perform specific task and find the path to send data. Router is
also called internet working device.
Our personal computer can act as
router. This type of router is called system router.
A device which is specially designed
for communication among different networks is called hardware router.
router is more efficient because it is specially designed for communication
among different networks and it is faster than software router.
Router can be create table that is
called routing table. It will transfer packet with the help of table from
source to destination. It will contain all the possible information about
destination. e.g. IP address , different paths etc.
Worked in Network Layer:
Router can be work in the third
layer of OSI Model. In network layer different network are communication with
one another. The router is used to connect the network layer. Router can
connect different network layer for communication.
transfers from source to destination are shown in figure.
Router inter Component:
There are some component that is used in router are
Packet buffer, Running
configurations, running IOS
Rom Monitor, Baby IOS
Backup configurations, Config register
Type of Router:
There are four types of router that is:
v Broad Band Router
v Wireless Router
v Edge Router
v Core Router
Broad Band Router:
The device that access to the
internet for multiple computers. Its typically includes a network switch with
four or more Ethernet ports for wired connection to desktop and laptop
Wireless routing creates a wireless
signal in your home or office. So, any computer within range of wireless
routers can connects it and used it. It works much like a wired router but
replaces wires with wireless radio signals to communicate to and external
Edge devices are that which provides
entry points into enterprise or service provider core networks. Examples
include routers, routing switches, integrated access devices, multiplexer and a
variety MAN and WAN access devices.
Core router is used to connect
Interface of Router:
There are two interface of router that is LAN
interface and WAN interface.
In Local Area Network, the router
connect multiple computers which are work in only one network.
v Are used to connect router to LAN
v Has a layer 2 MAC address
v Can be assigned a layer 3 IP
v Usually consists of an RJ-45 jack
In Wide Area Network, the routers
connect multiple networks for communication.
v Are used to connect router to
external networks that interconnects LANs
v Depending on the WAN technology,
a layer 2 address may be used
v Uses a layer 3 IP address
Type of Routing:
three type of routing that is:
v Static Routing
v Dynamic Routing
v Default Routing
In static routing, we use manual
configuration. Static routing is best for small networks. If we have less
devices then we use static routing. We can configure all the devices one by one
in this routing. We face difficulties to configure if we have large number of
devices one by one. Static routing is not flexible because if we save path in
routing table and it will be destroy some issue than the can’t find another
path to go to destination if there is another path is available in routing
table and not to find it. This type of routing is only depend on the
administration. There will be high overhead in this routing because
administration is check all the path and change if required. We can control the
routing in static routing.
In dynamic routing, we use automatic
configuration. Dynamic routing is best for large networks. If we have large
number of devices than we use dynamic routing. We can’t feel difficulties if we
have large no. of device because the configuration is automatic. If one path is
miss than this type of routing find another path to send data to destination
automatically. This is not depend on to the administration because it used
automatic configuration. There are less overhead in this routing. We are less
control the routing in this type as compare to static routing.
This type of routing
used manual configuration. So this is called static routing. Default routing is used to route
packets with destinations that do not match any of the other routes in the
There are two type of protocol in
router that is:
v Routed Protocol
v Routing Protocol
Routing protocol can find the no. of
router available than send the packet throw shortest best path. Routing
protocol is the communicate used between routers. Examples of routing protocol
v Routing Information Protocol
(RIP, RIP II)
v Open Shortest Path First (OSPF)
v Intermediate System to
Intermediate System (IS-IS)
v Interior Gateway Routing Protocol
v CISCI Enhanced Interior Gateway
Routing Protocol (CIGRP)
v Border Gateway Protocol (BGP)
This protocol can define the size and
format of packet. It is used to direct user traffic. Examples of router
v Internet Protocol
v Apple talk
An autonomous system (AS) is a
collection of networks under a common administration sharing a common routing
strategy. The outside world, an AS is viewed as a single entity.
of a routing protocol and autonomous systems:
v When all routers in an internetwork
are operating with the same knowledge, the internetwork is said to have
v Fast convergence is desirable because
it reduces the period of time in which routers would continue to make incorrect
v Autonomous systems (AS) provide the
division of the global internetwork into smaller and more manageable networks.
v Each AS has its own set of rules and
policies and an AS number that will uniquely distinguish it from other
autonomous systems throughout the world.
Classes of Routing Protocol:
Most routing algorithm can be
classified into two categories.
v Distance Vector
v Link State
The distance vector routing approach determines the direction
(vector) and distance to any link in the internetwork.
The link-state approach, also called shortest path first,
recreates the exact topology of the entire internetwork.
v Connecting an internet modem directly
to a PC exposes that PC to a host of security issues.
v A router is not a replacement for a
firewall or anti malware measures, but it’s an important first step toward a
largely secure network environment.
v Router can connect different media
v Router can determine the
best/shortest path to send data to the destination.
v Routers are more expensive than Hub,
Bridge and Switch.
v Routing update consume bandwidth.
v Router can add additional IP-based
headers. These headers include information such as source and destination
addresses, UDP information and checksum. These headers attached to every
payload of data.
v Large piece of data are typically broken into thousands of
smaller headers, making this header data consume a percentage of the total