Black Box Compact T1 MT850A, Руководство пользователя

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Glossary-8 Compact T1 - Release 6.1
Glossary
firewall
firewall Any of a number of security schemes that prevent unauthorized users
from gaining access to a computer network and/or may monitor the
transfer of information to and from the network.
frame A fragment of data that is packaged into a frame format, which comprises
a header, payload, and trailer.
Foreign
Exchange A Central Office trunk which has access to a distant central office. Dial
Tone is returned from that distant Central Office, and a location can be
reached in the area of the foreign Central Office by dialing a local
number. This will provide easier access for customers in that area and
calls may be made anywhere in the foreign exchange area for a flat rate.
Foreign
Exchange
Service Foreign exchange (FX) service is a service that can be ordered from the
telephone company that provides local telephone service from a central
office which is outside (foreign to) the subscriber’s exchange area.
Simply, a user can pick up the phone in one city and receive a dial tone
in the foreign city. This kind of connection is provided by a type of trunk
called foreign exchange (FX) trunk. FX trunk signaling can be provided
over analog or T-1 links. Connecting POTS telephones to a computer
telephony system via T-1 links requires a channel bank configured with
FX type connections.
G.168 Echo cancellation
G.711 Pulse code modulation (PCM) of voice frequencies. This ITU-T
Recommendation provides the rules for encoding of voice-frequency
signals to and from 64 kbps PCM. It covers both "A-law" and "µ-law"
encoding.
G.726 40, 32, 24, 16 kbps adaptive differential pulse code modulation
(ADPCM). This ITU-T Recommendation specifies the conversions of a
64 kbps A-law and u-law PCM channel to and from ADPCM encodings
of 40, 32, 24, and 16 kbps. (The PCM encoding is defined in G.711.)
gateway An entrance and exit into a communications network
GRE tunneling Generic Routing Encapsulation tunneling is a Layer 2 protocol that can
tunnel multi-protocol traffic over IP Networks.