Telephone exchangeW
Telephone exchange
CentrexW
Centrex
Deakin Telephone ExchangeW
Deakin Telephone Exchange
Director telephone systemW
Director telephone system
ElastixW
Elastix
IssabelW
Issabel
Main distribution frameW
Main distribution frame
Marker (telecommunications)W
Marker (telecommunications)
Message sequence chartW
Message sequence chart
Nonblocking minimal spanning switchW
Nonblocking minimal spanning switch
Nortel MeridianW
Nortel Meridian
PbxnsipW
Pbxnsip
Business telephone systemW
Business telephone system
DMS-100W
DMS-100
Rotary systemW
Rotary system
Telephone switchboardW
Telephone switchboard
TrixboxW
Trixbox
TXEW
TXE
Wire spring relayW
Wire spring relay