User manual

Connections to the Telephone Network 77
Connections to the Telephone Network
Figure 28 illustrates connections to the PSTN (Public Switched Telephone Network) using the T1 Modem Bank.
With PSTN, a modem modulates serial data into voice-like signals for transmission. At the receiving end of a circuit,
or connection, another modem demodulates the information, converting it back to serial data. Note that various
applicationssuch as 800 services, bulletin board services, the World Wide Web, and FAX servicescan be
accessed via the PSTN and long distance service.
The T1 Modem Bank provides an excellent resource for Remote Access Services (RAS). RAS enables users to
remotely dial-in to a local office and upload/download files for applications. The remote PC connects to the server
via V.34, V.32bis, and V.32 asynchronous modems. TELNET, FTP, and PPP connections between remote offices
and a local office can also be made.
Figure 28 T1 Modem Bank and Public Switched Telephone Network