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?
- Its all fiber these days. Maybe digital microwave as a backup on some routes, but these are rare, few and far between.
- It all depends on what carrier you use and how long the call is. Calls may go through an intermediate tandem if the call is cross country, or crosses from one country to another via a "gateway" switch.
- Rerouting is almost not an issue anymore. There is so much extra capacity that if there is more than one route to a destination, rerouting is automatic.
- As far as I know, the NOC in Bedminster still exists. After SBC takes over, who knows?
- I'm sure that these centers are still needed to maintain large networks. I'm sure MCI and Sprint have similar NOCs.
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.
These days, everyone buys from everyone else, so who knows where your call actually goes. Also, there are many wholesale providers that work with any and all LD providers (Level 3 comes to mind as one of these). Its not as cut and dry as it once was.
Dave Perrussel Webmaster - Telephone World
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