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NETWORK SWITCHING

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Submitted By “ Adarsh Arya
Roll No. 4315

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Methods of Switching
¢ Circuit Switching
¢ Message switching
¢ Packet Switching

Circuit Switching
¢ Seeking out and establish a physical path end-to-end.
¢ Circuit switching implies the need to first set up a dedicated end-to-end path for the connection before information transfer take place.
¢ Once the connection is made the only delay is propagation time.

Message Switching
¢ A store-and-forward network where the block of transfer is a complete message.
¢ Since messages can be quite large, this can cause:
“ buffering problems
“ high mean delay

Store-and-Forward Networks
¢ Each block is received in its entirety, inspected for errors, and retransmitted along the path to the destination. This implies buffering at the router and one transmission time per hop.

Packet Switching
¢ A store-and-forward network where the block of transfer is a complete packet. A packet is a variable length block of data with a tight upper bound.

Packet Switched Networks
Connection-oriented Protocols
“ A setup stage is used to determine the end-to-end path before a connection is established.

Connectionless Protocols
“ No set up is needed.
“ Each packet contains information which allows the packet to be individually routed hop-by-hop through the network.

Datagram vs Virtual Circuit
Datagram
“ Each datagram packet may be individually routed.
Virtual Circuit
“ Virtual circuit set up is required.
“ All packets in a virtual circuit follow the same path.