This came up before but perhaps things changed.
I call, say Wilmington Delaware to Milwaukee, Wisconsin. How and who is the call physically routed and connected between the two cities? What about a shorter call, say Harrisburg PA to Erie PA (a few hundred miles)?
By how, I mean what physical medium is chosen and how is it routed. Do they use satellite, microwave, fibre optic, coax, plain wire? Are there direct routes or must it go to intermediate switching centers and transferred there? What happens if the primary circuits are busy -- do they go to a lot of trouble to reroute or just cut me off? Does AT&T still have a big network control center in Bedminster? Does anyone even have such control centers or are they not needed anymore?
By whom I mean does my designated long distance carrier actually physically carry the call or do they merely sublet to someone else who actually owns the wires to where I'm going. Who manages the switching centers? I suspect a heck of a lot of long distance traffic is carried by someone other than the designated carrier.
Thanks!
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