RFC 2637:Point-to-Point Tunneling Protocol (PPTP)
RFC-Ref

PSTN


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... 1) Physical native interfacing to PSTN or ISDN and control of external modems ...
... terminal endpoints on a PSTN or ISDN -- for example, a telephone call ...
... An end-system or router attached to an on-demand PSTN or ISDN which is either the initiator ...
... network access to users. This access is point-to-point using PSTN or ISDN lines. ...
... PAC) A device attached to one or more PSTN or ISDN lines capable of PPP ...



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