Binary - Michael Crichton [4]
'You've got a guard already,' Graves said.
'There's a lot of expensive equipment to look after,' Phelps said. They made a right turn and entered a conference room.
There were just four of them: Graves; Phelps, looking springy and alert as he greeted everyone; Decker, who was thin and dark, intense-looking; and Venn, who was nearly fifty, greying, sloppy in his dress. Graves had never met Decker or Venn before, but he knew they were both scientists. They were too academic and too uncomfortable to be anything else.
Phelps ran the meeting. 'This is John Graves, who is the world's foremost expert on John Wright.' He smiled slightly. 'Mr Graves has plenty of background, so you can speak as technically as you want. Decker, why don't you begin.'
Decker cleared his throat and opened a briefcase in front of him, removing a sheaf of computer printout. He slipped through the green pages as he spoke. 'I've been working in Special Projects Division for the last six months,' he said. 'I was assigned to establish redundancy programmes on certain limited-access files so that we could check call-up locations to these data banks, which are mostly located in Arlington Hall in Washington.'
He paused and glanced at Graves to see if the information was making sense. Graves nodded.
'The problem is basically one of access-line proliferation. A data bank is just a collection of information stored on magnetic tape drums. It can be anywhere in the country. To get information out of it, you need to hook into the main computer with an access substation. That can also be anywhere in the country. Every major data bank has a large number of access substations. For limited or special-purpose access - stations that need to draw out information once or twice a week, let's say - we employ commercial telephone lines; we don't have our own lines. To tie in to a peripheral computer substation, you telephone a call number and hook your phone up to the computer terminal. That's it. As long as you have a half-duplex or full-duplex telephone line, you're in business.'
Graves nodded. 'How is the call number coded?'
'We'll come to that,' Decker said, looking at Venn. 'For now, we'll concentrate on the system. Some of the major data banks, like the ones held by Defence, may have five hundred or a thousand access lines. A year ago, Wilkens' congressional committee started to worry about unauthorized tapping into those access lines. In theory, a bright boy who knew computers could tap into the system and call out any information he wanted from the data banks. He could get all sorts of classified information.'
Decker sighed. 'So I was hired to install redundancy checks on the system. Echo checks, bit additions, that sort of thing. My job was to make sure we could verify which stations drew out information from the data banks, and what information they drew. I finished that work a month ago.'
Graves glanced at Phelps. Phelps was watching them all intently, pretending he was following the discussion. Graves knew that it was over Phelps' head.
'Just before I finished,' Decker said, 'we discovered that an unauthorized station was tapping into the system. We called it Sigma Station, but we were unable to characterize it. By that I mean that we knew Sigma was drawing information, but we didn't know where, or how.'
He flipped to a green sheet of computer printout and pushed it across the table to Graves. 'Sigma is the underlined station. You can see that on this particular day, July 21st, 1972, it tapped into the system at ten oh four PM Eastern time and maintained the contact for seven minutes; then it broke out. We determined that Sigma was tapping in at around ten o'clock two or three nights a week. But that was all we knew.'
Decker turned to Venn, who said, 'I came into the picture at this point. I'd been at Bell Labs working on telephone tracer mechanisms. The telephone company has a problem with unauthorized calls - calls verbally charged to a phone number, calls charged to a wrong credit card number,