I have vague recollection of ther system which I used after 1987 till the 1990s. I remember having booked even for journeys starting from different stations by 1989 or so...I will try and get the info on the PRS progress from the net. In the meanwhile have a look at this Concert. It says concert came in Mumbai and chennai in 1999 and I cant beleive that telephone lines/internet was used. Here is something on Concert from the indianrail.gov site NTRODUCTION :
CONCERT - COUNTRY-WIDE NETWORK FOR COMPUTERIZED ENHANCED RESERVATION AND TICKETING - developed by CRIS, Chanakya Puri, New Delhi, is a total networking solution to Indian Railways Passenger Reservation System. Indian Railways computerized Passenger Reservation System (PRS) currently operates from five regional centers located at Delhi, Bombay, Calcutta, Madras and Secunderabad. CRIS was assigned the task of development and implementation...
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of the new software incorporating networking for Indian Railways thereby interconnecting the five PRS centers. The new On-line Passenger Reservation System -CONCERT - developed using client-server model for distributed computing is a total solution to the networking of the PRSs. A dedicated team of software professionals contributed to the successful implementation of CONCERT. The software has been successfully implemented at all of the five PRS' site viz. Secunderabad in Sept. 1994, and New Delhi in Sept. 1996,Calcutta 14th June 1998 and recently at Mumbai on 11th Jan 1999, and at Chennai on 12th April 1999 thus the complete network become operational on 18th April 1999, and has been working satisfactorily since then. All of the five sites have been internet-worked over a 64 kbps line using routers, on leased communication line connections from Department of Telecom (DOT). Thus PRS network of the Indian Railways will enable reservations in any train, date, or class, between any pair of stations to the traveling public on about 2000 terminals across the country. Under the network environment it is proposed to provide; Universal Terminals. Universal Terminals are those from where any reservation activity on network can be done transparently. For any further information about CRIS, you may contact Web Master, CRIS criswebmaster@rediffmail.com.