Fault tolerance - A method of making a computer system or network resilient to faults or breakdowns to avoid lost data and downtime. For servers this involves such techniques as disk mirroring, disk duplexing or mirrored servers. For LANs and WANs it may involve the use of multiple redundant transmission links. Fax server - A specialized IVR system which sends facsimile messages to a fax machine designated by DTMF tones. What amounts to a database of fax text resides in the server that is accessed via a user's DTMF phonepad.
Requests result in the fax pages being delivered to the chosen fax and the subscriber charged a fee.
Typical applications of FDDI are in the area of high speed LAN backbones. This lets the file server regulate communications among the workstations connected to it across the LAN, and to manage shared resources available on the file server, such as hard disk storage and printers. Flow control - The procedures for controlling the rate of transfer of data between two points in a data network, such as between a protocol converter and a printer. This avoids data loss when a recipient device's buffer is full. Buffers play an essential role in overall flow control in a network.