Switching in computer networks2019
SWITCHING TECHNOLOGY:-
· SWITCHING TECHNOLOGY ALLOW HOW THE NETWORK DEVICES CONNECTED IN NETWORKING AND HOW DATA PACKETS FORWORDS FROM ONE PLACE TO OTHER.
· IN NETWORK SWITCHING WE USE DIFFERENT NETWORK LIKE SWITCH, HUB, ROUTER, BRIDGE AND GATEWAY WHICH USED TO ESTABLISH CONNECTION NETWORKS.
· NETWORK DEVICE MOSTLY USED AT NETWORK LAYER AND DATALINK LAYER AT OSI MODEL.
THER ARE TWO TYPE OF SWITCHINGà
PACKET SWITCHING
CIRCUIT SWITCHING
PACKET SWITCHING:- PACKET SWITCHING IS NOT REQUIRED TO ESTABLISH THE CONNECTION INITIALY.
· IN PACKET SWITCHING THE CONNECTION/CHANEL IS AVAILABLE TO USE BY MANY USER. BUT WHEN CAPACITY OR NUMBER OF USERS INCREASES THEN IT WILL LEAD TO CONGESTION IN NETWORK
· PACKET SWITCHED NETWORKS ARE MAINLY USED FOR DATA AND VOICE APPLICATION REQUIRING NON-REAL TIME SCENARIES.
· IN PACKET SWITCHING, STATION BREAK LONG MESSAGE INTO PACKETS. PACKETS ARE SENT ONE AT A TIME TO THE NETWORK.
· IN PACKET SWITCHING PACKET ARE RE-ARRANGED AT THE END OF RECEIVING END.
CIRCUIT SWITCHING:- IN CIRCUIT SWITCHING NETWORK DEDICATED CHANNEL HAS TO BE ESTABLISHED BEFORE THE CALL IS MADE BETWEEN USERS.
· THE CHANNEL IS RESERVED BETWEEN THE USER TILL THE CONNECTION IS ACTIVE.
· CIRCUIT SWITCHING USE HALF DUPLEX DATA TRANSMISSION.
· FOR HALF DUPLEX COMMUNICATION, ONE CHANNEL IS ALLOCATED TO THE TWO USER.
· CIRCUIT SWITCHING IS MAINLY USE FOR VOICE COMMUNICATION REQUIRING REAL TIME SERVICES WITHOUT ANY MUCH DELAY.
DIFFERENCE BETWEEN CIRCUIT SWITCHING AND PACKET SWITCHING
CIRCUIT SWITCHING |
PACKET SWITCHING |
DEDICATED PATH |
NO DEDICATED PATH |
PATH IS ESTABLISHED FOR ENTIRE CONVERSATION |
ROUTE IS ESTABLISHED FOR EACH PACKET |
CALL SETUP DELAY |
PACKET TRANSMISSION DELAY |
OVER LOAD MAY BLOCK CALL SETUP |
OVERLOAD INCREASE PACKET DELAY |
FIXED BAND WIDTH |
DYNAMIC BANDWIDTH |
NO OVERLOAD BITS AFTER CALL SWTUP |
OVERHEAD BITS IN EACH PACKET |