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Force system to make it clear. Communication between points became a problem a
long tim~ ago - I won't go into that, sir - when it became necessary to
somehow handle several messages at the same time. A line that delivers a
message is called a channel, and first through microwave and later through
laser-beam technologies, we now have channels that can transmit over a
thousand simultaneous messages at once, as for instance with the one thousand
channel system that links Pittsburgh, Cincinnati, and Chicago. There the
delivery potential is one thousand times one thousand. A lot of messages.'
'O.K. I understand you so far,' Judd acknowledged.
'Sophisticated systems of communications literally dissolve distances between
other systems that are fully electronic, transistorised high-speed
data-transmission mechanisms all linked together by electronic switching
centres that permit all this instantaneous transmission to any part of the
world. There are even electronic sentinels that monitor and provide for
switching between various microwave and wire-line channels - such as the
Atlantic cable system.' Abrams said this last with emphasis.
163
'O.K., O.K.' Judd grinned.
'Well, sir, there are all types of switching systems, all fully automatic
transistorised high-speed systems that can accommodate up to
two-hundred-words-per-minute circuits.'
'What he means to say, there,' interrupted Caogan, 'is that words in a lengthy
message can l)e fed into computer codes, indexed, and broken down into a
series of impulses that can then be sent in seconds to a distant place, there
to be decoded by a recipient computer that eventually prints Out the message.'
'Yes, ma'am,' continued Abrams. 'The Air Force Data Communications System, AF
DATACOM, is one such system that interlocks Air Force systems worldwide. It
accounts for millions of channel miles of microwave systems, but, as I
indicated, there are electronic sentinels that can be computer-commanded to,
intercept and feed the message into wire-line systems as necessary; News
media, worldwide, use lots of wire-line systems, the
familiar telex systems.'
'All right' - Judd grimaced - 'where and how did our man lock into the
systems?'
"Well, sir. . .'
'Oh, my'God !' gasped Coogan.
'Ah, you understand, Dr Coogan. Do you want to take over now?' Abrams asked.
'No. . . no, Lieutenant, please continue.'
'Do you understand what Abrams is talldng about?' asked Judd.
'Very clearly, very clearly,' Coogan said. 'And I think we're really in big
trouble now.'
'All right. Then continue, Abrams,' Judd said softly.
'Well, sir, three things would be needed. The appropriate codes that would get
entry into any of the various systems, a piece of equipment called a KE-CRT
terminal, and, finally, a telephone.'
'A telephone?'
'What he means, Harrah, is a keyboard-printer unit
that can be portable and can be coupled with an ordinary telephone receiver.
Many systems, in fact the majority of them, I'd say, can be accessed by
dialling a specific telephone number which is answered by a computer
somewhere. The receiver is then placed in the telephone coupler on the KB-CRT
terminal, and the terminal sends the message through the telephone receiver by
frequency codes? and it's decoded by the receiving computer.'
'Right, ma'am. This type of network access can be had at any point where a
standard telephone and an electrical outlet are available, providing, of
course, that you also have at least a portable KB-CRT unit.'
The trio lapsed into a momentary silence. Judd pursed his lips. Coogan began
scribbling a list.
'Are we to assume, then, that our person possesses, or possessed, a, what did
you call it, a KB-CRT terminal?' Judd finally asked.
'We are working on that, sir. CIA, FBI, and Defence Intelligence are, all busy
tracking down anyone who ever bought one of these units,' Abrams responded.
'This all gives me an idea,' Coogan said. 'Computer technology isn't so old.
Even though there must be thousands of people who have studied computer
programming,
it would be worth the effort to compile a list from all computer training
centres.'
'That would be a long list, even if the profession is that new,' commented
Judd.
'Yes, but if one of those names was in my yellow files here, we would be on to
something!'
'Can we do that, Abrams?' demanded Judd, hopefully.
'Can do, sir. If I'm not mistaken, computer trainees' names should be in
computers somewhere.'
'We also need to know who really knows about advanced computers,' Coogan
stated. 'Obviously, for someone to understand a global system, it would have
to be someone who understood more than the simplicities of the CRT units.
Start with UNIVAC trainees, Abrams. Try the IBM schools, especially the IBM
2741s, also the Tele165
type models 33 and 37, Memorex 1240 and 1280, TermiNet 300s, the Syner-Data
Betas and the AJ 841s. Here's a list.' She scribbled rapidly.
'Get anyone who has subscribed to code access lists and numbers,' continued
Judd. [ Pobierz całość w formacie PDF ]