A connection to the Internet using a telephone line and modem can serve up to 10 simultaneous users. Modem connections are often called slow links because data is transferred at the speed of the modem, typically from 9,600 to 28,800 bits per second.
Dial-up connections require the TCP/IP suite of protocols, as do all connections to the Internet. Specifically, dial-up connections require the Internet Protocol (IP). ISPs generally refer to dial-up connections as IP accounts. Variations of IP accounts are based on the TCP/IP line protocol used by the IP account. The following list describes the three variations of IP accounts:
PPP, which stands for Point - to -Point Protocol
SLIP, which stands for Serial Line Internet Protocol
CSLIP, which is a compressed version of SLIP
PPP is the current standard for encapsulating IP data and other network layer protocol information over point-to-point links. It also provides ways to test and configure lines and the upper level protocols of the Open Systems Interconnectivity (OSI) network architecture. PPP is an improvement over SLIP, which does not provide error correction.
To connect an Internet Information Server computer to the Internet, request a PPP account from your ISP. The PPP account is faster and more reliable than the other line protocols and is fully supported by the TCP/IP implementation under Windows NT Server and Windows NT Workstation.
Note
Point-to-Point Tunneling Protocol (PPTP), which is a feature provided by Windows NT Server and Windows NT Workstation version 4.0, essentially converts PPP information into point-to-point packets transmitted by TCP to provide a secure "tunnel" through the Internet. For more information, see the Windows NT Server Networking Supplement.