Computer Networks

• In computer networks, information streams are generally not very steady.
• Traffic in computer networks is often called bursty.
• E.g., when a WWW page is requested, the server sends the contents of the page as quickly as possible. At other times, nothing is received from that server.
• In this scenario, it would be wasteful to create a dedicated circuit between the WWW server and the requesting client.
• Instead, in computer network each burst or packet of information is switched individually.
• This is referred to as packet switching.
• In computer networks, switching is often called routing and switches are called routers.
• Notice that the idea of packet switching implies that each packet contains information about its destination.
• Packets contain source and destination addresses to allow routers to decide which of its attached links a packed should be forwarded on.
• Routers are often genaral purpose computers with multiple network connections.
• They receive packets on one network connection, process them in turn, and forward them via a different network connection.
• The term store-and-forward networks is also used for packet-switched networks.