Wide Area Networks
A wide area network (WAN) spans relatively large geographical areas. Connections for these sites require the use of ordinary telephone lines, T1 lines, ISDN (Integrated Services Digital Network) lines, radio waves, or satellite links. WANs can be accessed through dial-up connections, using a modem, or leased line direct connection. The leased-line method is more expensive but can be cost-effective for transmission of large volumes of data.