ADTRAN 1200212L1, Руководство пользователя

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61200212L1-1 DSU IQ User Manual D-1
Appendix D
Glossary
American National Standards Institute (ANSI)
Devices and proposes recommendations for international communications stan-
dards.
asynchronous
A method of data transmission which allows characters to be sent at irregular
intervals by preceding each character with a start bit, followed by a stop bit.
backward explicit congestion notification (BECN)
A bit set by a frame relay network to notify an interface device (DTE) that con-
gestion avoidance procedures should be initiated by the sending device.
bandwidth
The bandwidth determines the rate at which information can be sent through a
channel (the greater the bandwidth, the more information that can be sent in a
given amount of time).
bridge
A device that supports LAN-to-LAN communications. Bridges may be
equipped to provide frame relay support to the LAN devices they serve. A
frame relay capable bridge encapsulates LAN frames in frame relay frames and
feeds them to a frame relay switch for transmission across the network. A frame
relay capable bridge also receives frame relay frames from the network, strips
the frame relay frame off each LAN frame, and passes the LAN frame on to the
end device. Bridges are generally used to connect LAN segments to other LAN
segments or to a WAN. They route traffic on the Level 2 LAN protocol (e.g. the
Media Access Control address), which occupies the lower sub-layer of the LAN
OSI data link layer. See also router.