What is router?

This tutorial covers everything one like to know about networking basics including circuit switching vs packet switching, TCP/IP protocol fields, ARP/RARP protocol fields, what is IP address ,what is MAC address, networking devices which include hub, switch, bridge, router, gateway and firewall.


• Circuit Switching vs Packet switching   • LAN vs WAN vs MAN   • What is an IP address   • What is MAC Address   • Basics of OSI and TCP-IP Layers   • What is Hub   • What is Switch   • What is Bridge   • What is Router   • What is Gateway   • Firewall basics   • TCP-IP Packet format   • ARP Protocol format  


This page describes what is router in networking,funtion of router with ATM to LAN routing example.

A device used to link two or more networks. Router operates at OSI layer 3. Internetworking among dissimilar sub networks is achieved by using routers to interconnect the sub networks. It is essential that the router must perform following functions. 1. Provide a link between networks 2. Does routing of data between processes running on two end systems which are on two different networks and hence delivery of data happens. 3. Hence networking architecture of sub-networks need not have to be changed to interoperate both. Let us understands router's main task of internetworking with following example. Following figure depicts how router does internetworking between ATM connected server and 802 LAN connected work station.

router fig1

As mentioned in above figure this router will have protocols up to Layer3 for both ATM as well as LAN networks. This router takes care of both server and work station communication with each other. 1. When TCP/IP packet comes from server to router, router will remove ATM protocol headers and insert LAN compatible headers from Layer 1 to Layer 3 and pass packet to LAN networks. 2. Similarly when TCP/IP packet comes from work station to router, router will remove LAN protocol headers and insert ATM compatible headers from Layer 1 to Layer 3 and pass packet to ATM networks. Following figure describes protocols at ATM based server, LAN based work station and protocols at router. This figure is taken from book by william stallings as mentioned below to describe routing concept.

router fig2

Today there are routers available for latest broadband technologies viz. LTE, WiMAX and so on which takes care of interworking as explained to make to different networks talk to each other.

Router Vendors

WLAN: This page covers various popular wifi router suppliers with technical specifications. It covers DLINK,Linksys and Netgear.

LTE-wimax: This page covers various LTE and wimax routers suppliers with specifications. It covers LTE routers which can be interfaced with wimax networks on one side and LTE on the other side.

What is?

what is wlan?   what is wimax?   what is lte?   what is 4G?   what is 3G?   what is an ip address?   what is mac address?   what is modulation?   what is FPGA?   what is DSP?   what is RF?   what is wireless ?   what is zigbee?   what is Bluetooth?   what is lightwave RF?   what is z-wave?   what is microcontroller?   what is GSM?   what is CDMA?   what is GPRS?   what is infrared?  

RF and Wireless Terminologies