ROUTER BASICS

Router Basics : Mode and Interfaces.

There are two types of components in router .

1. external components:

(a).  serial port:- Router to router connectivity.

(b).External port:_- lan connectivity.

(c). AUI:- Additional lan port.

(d). AUX:- Wan connectivity through modem.

(e). Consol port:- To confiqure the router/switch from another computer.

Internal component;-

(a). Motherboard:- Gives a plateform to connect all device.

(b). ROM:- it is stand for Read Only Memory .it is used to read and write data.

(c). RAM:- It is a volatile memory .it hold only active configuration & running configuration of router. it  hold routing table & Arp table.

(d). NV-RAM:- It is non-volatile memory,which is startup configuration.

Flash Memory:- It conten's IOS of router.

Mini IOS:- it provides to installed IOS of router,whome IOS is not present in flash memory.

configuration resister value in router:-

It is 16 bit value which is represented in hexadecimal formate that fells the router form whoes it will boot.

there are four types of resister value.

(1). 0x2100 tell the router to boot from rom monitor mode (safe mode).

 (2). 0x2101:- To boot from mini ios.

(3). 0x2102:- to boot from flash with nvram/startup confiquration. it is default configuration resister value.

(4). 0x2142:- Boot from flash ,but ignore nvram configuration.

Flow chart of Router/Boot sequence :

1. POST.:

 2. Boot Strap:

 3. Flash:

4. NVRAM:

5.RAM: