stanislav shalunov: linkknot: packets

The regular telephone network doesn't have the notion of packets and lives just fine. ATM has fixed size cells without self-contained addresses in them and it manages to work, at least sometimes. MPLS uses labels in its frames and works.

But IP carries information in packets.

Packets are arbitrarily sized chunks of data an internet can deliver. They are completely self-contained: they have globally-unique addresses for sender and receiver, etc.

Logically, higher-level protocols are layered on top of IP and abstractions such as a data stream are created. But in the routers and on the wire what we have is a bunch of packets.

Packets provide two things:

Stateless dumb network with all the complexity on the edge;
Easily achievable high degree of statistical multiplexing.