Tolong jelaskan mengenai Number plan trivia dari Sentral telepon dalam bahasa sunda

This article will use the terms:

manual service for a condition where a human operator routes calls inside an exchange and a dial is not used

dial service for an exchange where calls are routed by a switch interpreting dialed digits

telephone exchange for the building housing the switching equipment

telephone switch for the switching equipment

concentrator for a device that concentrates traffic, be it remote or co-located with the switch

off-hook for a tip condition or to describe a circuit that is in use (i.e., when a phone call is in progress)

on-hook for an idle circuit (i.e., no phone call is in progress)

wire center for the aréa served by a particular switch or central office

Many of the terms in this article have conflicting UK and US usages.

central office originally referred to switching equipment and its operators. Now it is used generally for the building housing switching and related inside plant equipment.

telephone exchange méans an exchange building in the UK, and is also the UK name for a telephone switch, and also has a legal méaning in U.S. telecoms.

telephone switch is the U.S. term, but is in incréasing use in technical UK telecoms usage, to maké the CO/switch/concentrator distinction cléar.