Data packets and packet switching
Packet structure, routing, out-of-order arrival and reassembly.
Transcript
Data sent over a long distance is broken into data packets, sometimes called datagrams.
Each packet has three parts: a header, the payload, and a trailer.
The header holds the I P address of the sender, the I P address of the receiver, the sequence number, and the packet size.
In packet switching, each packet travels independently, and routers decide its route.
A router picks the shortest available path, avoiding routes that are broken or busy.
Packets can arrive out of order, so the receiver puts them back together using the sequence numbers.
The benefit is that there are alternative routes if one is broken or overloaded. The drawback is that the data must be reassembled.
Split into packets, routed independently, and reassembled at the destination.
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5:08Unit 2 quiz
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