Glossary
E
Centillion 1200N ATM Switch User Manual
B-25
NTP 297-8103-903
EFS
Error Free Seconds: A unit used to specify the error performance of T carrier
systems, usually expressed as EFS per hour, day, or week. This method gives a
better indication of the distribution of bit errors than a simple bit error rate (BER).
Also refer to SES.
ELAN
Emulated Local Area Network: A logical network initiated by using the
mechanisms defined by LAN Emulation. This could include ATM and legacy
attached end stations.
EMA
Emergency Controller
EMI
Electromagnetic Interference: 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.
EMI/RFI
ElectroMagnetic Interface/Radio Frequency Interface: A circuit or device
containing series inductive (load bearing) and parallel capacitive (non-load
bearing) components, which provide a low impedance path for high-frequency
noise around a protected circuit.
EML
Element Management Layer: An abstraction of the functions provided by systems
that manage each network element on an individual basis.
EMS
Element Management System: A management system that provides functions at the
element Management Layer.
EOM
End of Message: An indicator used in the AAL that identifies the last ATM cell
containing information from a data packet that has been segmented.