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Packet switching was invented by Donald Davies and Paul Baran in the early 1960s. Some people claim that Leonard Kleinrock also invented packet switching, but Davies contested this prior to his death and pointed out that Kleinrock's research was actually in queueing theory, which is of course a key theoretical underpinning to packet switching. However, Kleinrock's published works nowhere mention breaking a user's message up into segments, and sending the segments through the network separately, which was the key innovation in Baran's and Davies' work.
A packet is a block of user data together with necessary address and administration information attached, to allow the network to deliver the data to the correct destination. One data connection will usually carry a stream of packets of data that will not necessarily be all routed the same way over the physical network.
Analogous to a physical packet sent through the post with the address written on the outside, this provides the information the network (the postal service) needs to get the packet to the correct destination.
Packets are routed to their destination through the most expedient route (as determined by some routing algorithm). Not all packets travelling between the same two hosts, even those from a single message, will necessarily follow the same route.
The destination computer reassembles the packets into their appropriate sequence. Packet switching is used to optimise the use of the bandwidth available in a network and to minimise the latency. Ethernet, X.25 and Frame relay are international standard layer 2 packet switching networks.
Notably, the InternetThis article is about the Internet the extensive, worldwide computer network available to the public. An internet is a more general term for a set of interconnected computer networks that are connected by internetworking''. WWW information network structu is a packet-switched network, running the Internet ProtocolThe Internet Protocol IP is a data-oriented protocol used by source and destination hosts for communicating data across a packet-switched internetwork. Data in an IP internetwork are sent in blocks referred to as packets or datagrams (the terms are basica layer 3 protocol over a variety of other network technologies. Newer mobile phone technologies such as GPRS and i-modeNTT DoCoMo's i-mode is a wireless internet service for i-mode mobile phones using HTTP, popular in Japan and increasingly also elsewhere. It was inspired by the drawbacks of WAP being discussed at the time, and a rough concept aimed for businessmen introd also employ packet switching.
Also called connectionless. Opposite of circuit switchedIn telecommunication, the term circuit switching has the following meanings: 1. A method of routing traffic between an originator and a destination through switching centers, from local users or from other switching centers, whereby a continuous electrica or connection-oriented networking, although technologies such as MPLS are beginning to blur the boundaries between the two.