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Glossary and Abbreviations
emergency transfer
If a major system failure occurs, automatic transfer is initiated to a group of telephones capable of making outgoing calls. The system operates in this mode until the failure is repaired and the system automatically returns to normal operation. Also called
EMI
Electromagnetic interference
end-to-end signaling
The transmission of
enhanced private-switched communications service (EPSCS)
An analog private telecommunications network based on the No. 5 crossbar and 1A ESS that provides advanced voice and data telecommunications services to companies with many locations.
EPN
EPROM
Erasable programmable
EPSCS
Enhanced Private Switched Communications Services
ERL
Echo return loss
Erlang
A unit of traffic intensity, or load, used to express the amount of traffic needed to keep one facility busy for one hour. One Erlang is equal to 36 CCS. See also CCS or hundred call seconds.
ESF
Extended superframe format
ESPA
European Standard Paging Access
ETA
Extended Trunk Access; also Enhanced Terminal Administration
ETN
Electronic tandem network
ETSI
European Telecommunications Standards Institute
expansion archangel (EAA)
A
Issue 5 January 1998 |