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A LAN (local area network) is often thought of as a small network, usually not exceeding a few kilometers.
However, assuming we have an unlimited supply of quality wires and chips, is it possible to build a huge LAN spanning more than dozens of kilometres?
2
TP cables are specified to ~100 m. With repeaters, the limits from signal quality are in practice removed, and with intelligent devices lengths become more or less arbitrary (cf. the Internet). Your "common consensus" is probably that it's seldom needed to have larger areas covered. Building material, property costs, heating, etc. also weigh in. It is also good to limit the # of clients in an Ethernet segment since it runs on collisions, including other factors, but there is no physical limit. So to your first question: no
– Daniel Andersson – 2012-06-18T14:35:54.033