Clear and present danger - Tom Clancy [342]
"Machine language," the consultant explained. "Whoever programmed this baby was a real pro. I recovered about forty percent of it. It's a transposition algorithm, just like I thought."
"You told me that last night."
"It ain't Russian. It takes in a message and enciphers it. No big deal, anybody can do that. What's really clever is that the system is based on an independent input signal that's unique to the individual transmission-over and above the encipherment algorithm that's already built into the system."
"You want to explain that?"
"It means a very good computer lash-up - somewhere - governs how this baby operates. It can't be Russian. They don't have the hardware yet, unless they stole a really sexy one from us. Also, the input that adds the variable into the system probably comes from the NAVSTAR satellites. I'm guessing here, but I think it uses a very precise time mark to set the encryption key, one that's unique to each up-and-down transmission. Clever shit. That means NSA. The NAVSTAR satellites use atomic clocks to measure time with great precision, and the really sexy part of the system is also encrypted. Anyway, what we have here is a clever way of scrambling a signal in a way that you can't break or duplicate even if you know how it was done. Whoever set this baby up has access to everything we got. I used to consult with NSA, and never even heard of this puppy."
"Okay, and when the disk is destroyed… ?"
"The link is gone, man. I mean, gone. If this is what it seems to be, you have an uplink facility that controls the algorithm, and ground stations that copy it down. You wipe this algorithm off, like somebody did, and the guys you used to be talking to can't communicate with you anymore, and nobody else can communicate with them either. Systems don't get any more secure than that."
"You can tell all that? What else?"
"Half of what I just told you is informed speculation. I can't rebuild the algorithm. I can just tell you how it probably worked. The bit on the NAVSTAR is supposition, but good supposition. The transposition processing is partly recovered, and it has NSA written all over it. Whoever did it really knows how to write computer code. It's definitely ours. It's probably the most sophisticated machine code we have. Whoever got to use it must have some serious juice. And whoever it is, he scrubbed it. It can never be used again. Whatever operation it was used for must be over."
"Yeah," O'Day said, chilled by what he had just learned. "Good work."
"Now all you have to do is write a note to my prof and tell him why I missed an exam this morning."
"I'll have somebody do that," O'Day promised him on the way out the door. He headed for Dan Murray's office, and was surprised to see that he was out. The next stop was with Bill Shaw.
Half an hour later it was clear that a crime had probably been committed. The next question was what to do about it.
The helicopter took off light. Mission requirements were fairly complex - more so than in the previous insertions - and speed was important this time. As soon as the Pave Low got to cruising altitude, it tanked from the MC-130E. There was no banter this time.
Ryan sat in back, strapped into his place while the MH-53J bounced and buffeted in the wash of the tanker. He wore a green flight suit and a similarly green helmet. There was also a flak jacket. Zimmer had explained to him that it would stop a pistol round, probably, secondary fragments almost certainly, but that he shouldn't depend on it to stop a rifle bullet. One more thing to worry about. Once clear of the tanker for the first time - they'd have to tank again before making landfall - Jack turned around to look out the door. The clouds were nearly overhead now, the outlying reaches from Adele.
Juardo's wound complicated matters and changed plans somewhat. They loaded him into Clark's seat on the Beech, leaving him with a radio and spare batteries. Then Clark and the rest drove back toward Anserma. Larson was still checking the weather, which was changing on an hour-to-hour basis. He was