User manual

Adit 3104 - Release 1.6 Glossary-7
Glossary
Electro-magnetic Interference (EMI)
Electro-magnetic
Interference (EMI)
Equipment used in high speed data systems, including ATM, that generate and transmit
many signals in the radio frequency portion of the electromagnetic spectrum. Interference
to other equipment or radio services may result if sufficient power from these signals
escape the equipment enclosures or transmission media. National and international
regulatory agencies (FCC, CISPR, etc.) set limits for these emissions. Class A is for
industrial use and Class B is for residential use.
Ethernet Ethernet is a particular network topology and protocol, especially useful in LANs. It comes
in various speeds and is often regarded as THE current technology for general network
direct connection. The current connectivity is generally considered to be 10Base-T or
100Base-T, while the backbone, if one is used, is coaxial cable or Fiber optics. There is also
a 1000Base-T for certain specialty copper joining situations.
Facilities Data Link
(FDL)
FDL supports the communication of various network information in the form of in-service
monitoring and diagnostics.
filter An operating parameter used with routers that can be set to block the transfer of packets
from one LAN to another.
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.
Frame Reject (FRMR) The FRMR response frame is sent to report the receiver of a frame cannot successfully
process that frame and that the error condition is not correctable by sending the offending
frame again.
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.711 ITU-T Recommendation for an algorithm designed to transmit and receive A-law and mu-
law PCM voice at digital bit rates of 48, 56, and 64 Kbps. It is used for digital telephone
sets on digital PBX and ISDN channels.
G.729 International Telecommunications Union’s standard voice algorithm (CS-ACELP) voice
algorithm for the coding of encoding/decoding of speech at 8 Kbps using conjugate-
structure, algebraic-code excited linear predictive methods. Described in the ITU-T
standard in its G-series recommendations.