Paris network and numbering plan

Paris telephone network, based on the Rotary system developed well before the war, is now being expanded by new crossbar exchanges. Urban and suburban network which is fully automated comprises nearly 900 000 lines, regional area 1 has 135 000 lines and is automated in 75%; regional area covers more remote localities and is quite independent. The organization of the network is described and illustrated by maps showing the disposition of transit, regional, etc. exchanges. All incoming international and national transit traffic is handled by one tandem exchange of crossbar type. The entire area is a 7-digit dialling area, with a prefix 1 added to form a national number; the numbers are composed of letters and numerals.