I&C SCI 11 Lecture Notes - Lecture 2: Packet Switching, Queuing Delay, Circuit Switching
Document Summary
Network application: end systems exchange info messages . Can hold data in forms such as text, images or audio. Packets: what messages are broken down into to be sent from one end system to another, route through comm links and packet switches, are transmitted on the comm links at equal to transmission rates of link. Store-and-forward transmission: what most packet switches use at comm links, packet switch must receive whole packet before breaking down and sending. Queuing delays and packet loss: packet switches have multiple links attached, output buffer. If the link is busy, then the packet meant to be sent through the link must be put into a delay in the output buffer. Makes for queuing delays: packet loss. When the buffer is completely full with other awaiting packets. Ip address: each end system has one, source end system includes destination ip address, forwarding table. Maps routes to destination addresses: router examines address.