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Re: Is Anonymous Communication only for "Criminals"?




Tim May wrote:
> (Even the _ability_ to block a pay phone, qua pay phone, must imply that
> pay phones send out some kind of signal announcing themselves as pay
> phones, which I had not heard of before. I assumed a pay phone was Just
> Another Phone Number.)

Telephone switches generate (receive) a digit that is known as Call Type.
Simplistically, Call Types may be 1+ for regular calls, 800 for 800 calls,
Conference, and 0+ for operator/payphone call.

One of the switch features may be some kind of call type blocking,
or passing the call type to the termination side, such as the pager
company computer.

	- Igor.