[Black Fleet Crisis(64)

“Very well. But I will consider this an axiom rather than a fact. “

“Here’s a fact. If I’d built it, there’d be at least two ways in-a front door, and a back door for when something goes wrong with the front door, ” Lando said. “But, I was saying-you don’t want to use a physical key, because you don’t want to let anyone that close without checking them out. So we’re talking about a password, basically. A really long binary password. “

“Forgive me, Master Lando, but in my experience no sentient being could remember a password of this length and complexity, ” said Threepio.

“The answer might not be as long as the question-” Lando began.

“It could be longer, ” said Lobot.

“That’s not the point. Maybe the question only looks long and complex because we don’t understand it. Human beings can remember incredibly long sequences if they have meaning, ” said Lando. “I knew a smuggler who’d memorized the Hundred Prescriptions of Alsidas when he was a kid taking religious training, and he could still rattle them off thirty years later. My mother knew hundreds of songs and poems by heart. And there are species with much better memories than human beings. “

“I don’t dispute that. There are many feats of memory recorded in the libraries, ” said Lobot. “Even so, passwords and access codes, whether mathematical or linguistic, are not error-tolerant. No matter how long the expected response may be, it must contain no errors. “

“Well, that’s always the problem, isn’t it? ” said Lando. “How do people remember all the things they have to remember? What do they do when there’s something they can’t allow themselves to forget? Some people have incredible memories, and others have trouble remembering their kids’ birthdays, much less their ID numbers and the access codes for digital locks they haven’t opened in years. So people cheat. “

“Mnemonics. “

“Yes, but they cheat in other ways, too, ” said Lando. “They carry the passcodes with them-“

“But that compromises security. Anything that’s carried can be stolen. “

“Right. So some try to disguise the passcode as something else-“

“That’s little better. Anything that’s hidden can be found. “

“Right again, ” said Lando. “A pickpocket on Pyjridj once told me that four of every five belt pouches he saw had passcodes in them, and it rarely took him even a minute to find them. Sometimes the passcode was the only handwritten item in the pouch. “

“You could ask a droid to remember the passcode for you, ” said Threepio. “A droid can be instructed to tell no one but you, does not make mistakes, and will not forget. “

“But droids can be stolen, just like pouches, ” Lobot said. “Droids can have their memories read, or wiped. Droids will dump their memory data under sensor-torture. Droids also know what it is that they know, which can lead to erratic behavior. Droids have revealed criminal acts by their owners, refused orders from their owners, wiped their own memories, destroyed themselves-” To Threepio’s seeming relief, Artoo interrupted the litany of failings with a trill.

“Artoo wishes to remind us that all combat astromechs have protected memory segments which can be used to store sensitive information, ” said Threepio. “He says that in more than thirty years of operation, no captured R2 unit has ever revealed the contents of a protected memory segment. “

“That’s fine, Artoo, ” said Lando. “You can tuck something away in your memory where even you won’t know what’s in it, so you can’t be forced to reveal it. But you can still be blown to bits or snatched away from me-and then what am I supposed to do? A little better shooting by the Empire, and the technical readouts on the Death Star would never have reached General Dodonna at Yavin. “

“The key must be replicable, ” Lobot said.

“Exactly, ” Lando agreed. “Otherwise the key itself is the weak point. Like having all your riches in a vault, and only one guy who knows where the only key is. Too risky. ” He stood and started to pace in the confined space ofLady Luck’s galley. “Come on, come on-we’re getting close to something here, I feel it. What haven’t we looked at? Where’s the missing piece? “

“What about the fact that there are pairs of tones in the transmission? ” asked Lobot.

“Good, good, ” said Lando rubbing his hands together.

“But are they pairs, or is it two separate channels of information? Do the individual modulations count, or just the pairs? Pairs, long sequences, replications, securely concealable-what kinds of information fit that description? “