Cisco Router

Define : Router
Router is a networking device which connects and enable different IPs and different geographical network to communicate with each other.
If there are multiple paths for the transmission and delivery of data, router determines the best path to transmit the data.
Manufacturer :
Cisco , Nortal, multicon, junifer, D-Link, Linksys
Cisco has Monopoly in the market of router

Cisco Three Layer

Three-tier Hierarchical Network Model

Cisco has developed a layered hierarchical model for designing a reliable network infrastructure.Benefits of using Cisco’s hierarchical model are network stability, reliability and cost-effectiveness.Cisco’s 3 Layered model consist of,

a) the Core layer
b) the Distribution layer
c) the Access layer

a) the Core layer : The core layer is main part of network,it transfer very heavy traffic in a short time.It is high speed router and switches.

Example : High speed WAN routers and switches

Cisco switches  7000, 7200, 7500, and 12000 for WAN use,
Cisco switches 4000, 5000 and 6000 series for LAN use.

b) The Distribution layer : It is a communication channel between the access and the core layer. It managed Routing, filtering, and QoS policies . It is smartest layer.

Examples : LAN routers, layer 3 switches.

c) the Access layer : the Access layer, also called the desktop layer, focuses on connecting client devices, such as workstations, laptops, servers and peripherals on the internal network (same broadcast domain).This layer usually incorporates Layer 2 switches and access points that provide connectivity between workstations and servers.

Cisco Router Configuration

Router can also be categorized into two types

Fixed Routers : Modification of interfaces is not possible.

Modular Router : Modification of interface is possible

Type of port in the router

A.U.I (Attachment Unit Interface) is 15 pin female known as Ethernet port or LAN port or default gateway

It is used to connect switch that connects LAN to the router

Transceiver is used for converting 8 wire into 15 wire for example RJ45 to 15 pin converter

Serial Port serial pin configuration is 16 pin cable configuration female.It is knows as WAN port.
Used for  remote Connection.

Console port also called as  local administrative port.Main purpose for this port is  initial configuration , password recovery . It is RJ45 port .

Auxiliary Ports : known as remote administration port used for remote administrator ,It is a RJ45 port , A console or a rollover cable is used.

B.R.I ( Basic Route Interface) used to connect ISDN to the router. it is RJ45 port .

10 BASE T Port is a RJ45 port used to connect LAN to the router.

Internal component of Router

ROM : A Bootstrap program is located in router. It is the same as BIOS PC bootstrap program .

Flash : Internetwork OS developed by cisco is started command line interface

NVRAM : Nonvolatile RAM similar to HD also known as permanent storage or startup configuration.

RAM : It is  temporary storage and have  running configuration. Minimum size of RAM is 2 MB.

Processor Motorola processor 70 Mhz IISC RISC(Reduce Instruction Set Computing) process.

BOOT SEQUENCE

POST – ROM – Flash – NVRAM – RAM

EMULATION SOFTWARE

Path start -> program -> Accessories -> communication -> hyperterminal
give connection name
and select any icon select series serial port where router is connected in Port setting click on restore default minicom managers