(1) (
Electronic
Switching
System) A large-scale computer used to route telephone calls in a telephone company office. The 5ESS is a Class 5 central office switch, and the 4ESS is a Class 4 tandem office switch. The ESS designation originated with AT&T when it manufactured the machines and was the only telephone company in the U.S. See
SS7,
Class 4 switch,
Class 5 switch and
digital cross-connect.
(2) (
Enterprise
Storage
Server) A family of SAN devices for mainframes and Unix servers from IBM. ESS units are built with a high degree of fault tolerance and connect via Fibre Channel, SCSI, ESCON and FICON interfaces. See
SAN.
(3) (
Executive
Support
System) See
EIS.
(4) (
Electronic
Spread
Sheet) See
spreadsheet.
(5) (
Extended
Service
Set) Two or more Wi-Fi access points in the same subnet. See
BSS and
802.11.