terminals can have access to Prestel. Thus the hacker thought that it should be possible to access the service with ordinary viewdata equipment instead of the special units supplied along with the annual subscription. Obtaining the phone number was relatively easy: it was simply a matter of selecting manual dial-up from the appropriate menu, and listening to the pulses as they went through the regular phone. The next step was to obtain a password. The owners of the terminal to which the hacker had access did not know their ID; they had no need to know it because it was programmed into the terminal and sent automatically. The hacker could have put a micro 'back-to-front' across the line and sent a ENQ to see if an ID would be sent back. Instead he tried something less obvious. The terminal was known to be programmable, provided one knew how and had the right type of keyboard. Engineers belonging to the service had been seen doing just that. How could the hacker acquire 'engineer' status? He produced the following hypothesis: the keyboard used by the service's customers was a simple affair, lacking many of the obvious keys used by normal terminals; the terminal itself was manufactured by the same company that produced a range of editing terminals for viewdata operators and publishers. Perhaps if one obtained a manual for the editing terminal, important clues might appear. A suitable photocopy was obtained and, lo and behold, there were instructions for altering terminal IDs, setting auto-diallers and so on. ** Page
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Now to obtain a suitable keyboard. Perhaps a viewdata editing keyboard or a general purpose ASCII keyboard with switchable baud rates? So far, no hardware difficulties. An examination of the back of the terminal revealed that the supplied keypads used rather unusual connectors, not the 270° 6-pin DIN which is the Prestel standard. The hacker looked in another of his old files and discovered some literature relating to viewdata terminals. Now he knew what sort of things to expect from the strange socket at the back of the special terminal: he pushed in an unterminated plug and proceeded to test the free leads with a volt-meter against what he expected; eight minutes and some cursing later he had it worked out; five minutes after that he had built himself a little patch cord between an ASCII keyboard, set initially to 75 baud and then to 1200 baud as the most likely speeds; one minute later he found the terminal was responding as he had hoped... Now to see if there were similarities between the programming commands in the equipment for which he had a manual and the equipment he wished to hack. Indeed there were: on the screen before him was the menu and ID and phone data he had hoped to see. The final test was to move over to a conventional Prestel set, dial up the number for the financial service and send the ID. The hacker himself was remarkably uninterested in the financial world and, after describing to me how he worked his trick, has now