Carrier Access Network Device Axxius 800, Руководство пользователя

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Glossary - 8 Axxius 800 - Release 2.2
Glossary
E&M Signaling
E&M Signaling
A signaling arrangement that uses separate leads, called respectively the
E lead and the M lead, for the signaling and voice signals. The M lead
(derived from ‘Mouth’) transmits ground or battery to the distant end of
the circuit, while incoming signals are received as either a grounded or
open condition on the E (derived from ‘Ear’) lead. The E&M tie trunk
interface functions as a de facto standard in the PBX - T1 multiplexer
Telco environment.
Earth ground
A wire conductor that terminates in the earth for electrical purposes. It is
generally the negative side of the circuit and is most important in
alternating current (AC) circuits. Chassis Ground is the general term
used in direct current (DC) circuits.
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.
File Transfer
Protocol (FTP)
An Internet protocol that enables you to transfer files between computers
on the Internet.
filter
An operating parameter used with routers that can be set to block the
transfer of packets from one LAN to another.