ADTRAN 1200275L1, Руководство пользователя

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Appendix D. Glossary
D-8 TSU IQ+ User Manual 61200275L1-1
framing
A control procedure used with multiplexed digital channels (such as T1 carriers)
where bits are inserted so the receiver can identify time slots allocated to each
subchannel. Framing bits may also carry alarm signals indicating specific alarm
conditions, cyclic redundancy checks (CRCs), and an out-of-band data channel
in the case of an extended superframe (ESF) T1 link. In T1 terminology, a frame
consists of 192 data bits and one framing bit.
gateway
A device which enables information to be exchanged between two dissimilar
systems or networks.
HDLC
high level data link control. 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 SDLC.
host computer
The primary or controlling computer in a multiple computer operation.
in-band
Signaling (dialing, diagnostics, management, configuration, etc.) over the same
channel used for data.
ingress
Frame relay frames leaving from an access device in a direction toward the
frame relay network.
interface device
Provides the interface between the end device(s) and a frame relay network by
encapsulating the user's native protocol in frame relay frames and sending the
frames across the frame relay backbone. See also encapsulation and frame-relay-
capable interface device.
IP
internet protocol. A protocol which provides for transmitting blocks of data
between hosts identified by fixed-length addresses.