61200.130L1-1 FSU User Manual 121
Glossary
file server
In the context of frame relay network supporting LAN-to-LAN communications,
a device connecting a series of workstations within a given LAN. The device
performs error recover and flow control functions as well as end-to-end
acknowledgment of data during data transfer, thereby significantly reducing
overhead within the frame relay network.
forward explicit congestion notification (FECN)
A bit set by a frame relay network to notify an interface device (DTE) that
congestion avoidance procedures should be initiated by the receiving device. See
also BECN.
frame check sequence (FCS)
The standard 16-bit cyclic redundancy check used for HDLC and frame relay
frames. The FCS detects bit errors occurring in the bits of the frame between the
opening flag and the FCS, and is only effective in detecting errors in frames no
larger than 4096 octets. See also cyclic redundancy check (CRC).
frame-relay-capable interface device
A communications device that performs encapsulation. Frame-relay-capable
routers and bridges are examples of interface devices used to interface the
customer's equipment to frame relay network. See also interface device and
encapsulation.
frame relay frame
A variable-length unit of data, in frame-relay format that is transmitted through
a frame relay network as pure data. Contrast with packet. See also Q.922A.
frame relay network
A telecommunications network based on frame relay technology. Data is
multiplexed. Contrast with packet switching network.
high level data link control (HDLC)
A generic link-level communications protocol developed by the International
Organization for Standardization (ISO). HDLC manages synchronous code-
transparent, serial information transfer over a link connection. See also
synchronous data link control (SDLC).