“What did you find?”
“Nothing to write home about. A piece of free-floating junk about the same size as the cutter. I grappled in and spacewalked. Took me about two minutes to find the right module and patch in a froptic. After that it was plain sailing.” His gently slanted eyes were pink-rimmed, as if he’d been up all night drinking vodka.
“Heard from Thalia since I left, Boss?” Dreyfus shook his head.
“I reckoned she’d work faster without me breathing down her neck every five minutes.”
“She’ll get the job done, don’t worry about that.”
“I sincerely hope so.”
“You have doubts?”
“I can’t help worrying. She’s a good deputy, but she’s barely out of school. I know she wants to prove to us all how good she is, but sometimes I think she’s overcompensating for what happened to her father.”
“What was your take on that?”
“I didn’t know Jason Ng all that well. But from what I did know, I never had cause to doubt his abilities or his dedication to Panoply.”
“So you were surprised?”
“We all were.”
“You ever talk to Thalia about it?”
“The subject’s never come up.”
Sparver smiled.
“She’d hardly be the one to raise it, would she?”
“Whatever I might think of her father, it has no bearing on my opinion of Thalia. I wouldn’t have selected her for my squad if I’d had doubts.” Dreyfus took his cup and sipped at it gently, blowing on the tea to cool it.
“Isn’t that all the reassurance she needs?”
“There are still prefects who won’t look her in the eye when she goes to the refectory,” Sparver said.
“I know how that feels.”
“They also resent her because she was promoted to Deputy Field One ahead of most of her classmates.”
“I just sometimes wonder if we truly understand what it’s like for her, working for the same organisation that tarred and feathered her father.”
Dreyfus shrugged. He had no real opinion on the matter. Jason Ng had been outwardly competent and trustworthy, but it was a matter of record that he had obstructed an investigation into a mid-rank habitat suspected of voting fraud. He had been found dead, having committed suicide in a cargo airlock. Postmortem audits revealed how Ng had been receiving bribes from parties connected to the habitat. He had killed himself because his culpability was about to be made public, and he wished to spare Thalia the shame of watching her father go through a humiliating tribunal.
Dreyfus didn’t care. He did not believe in an inherited disposition for accepting bribes or perverting investigations. If anything, he believed that Thalia would make a better prefect than many of her peers. She wanted both to redeem her father’s sins and show that she was not a slave to her genes.
“She’s a good deputy,” he said again.
“That’s all that matters to me. And I have every confidence that she’ll pull this off without our assistance.”
“You didn’t sound confident just now.”
“I’m entitled to entertain reasonable qualms. But that’s all they are. And face it, Sparv: Thalia chose to bite this one off on her own. She’d hardly welcome the arrival of a back-up squad, even if we could spare the personnel.”
“You’re right, as usual. I just have this horrible feeling that we’re dancing to someone else’s tune, spreading ourselves too thinly. We’ve got Thalia trying to seal the Perigal security hole; we’ve got you and me trying to nail whoever murdered Ruskin-Sartorious; we’ve got the rest of Panoply trying to keep the habitats and the Ultras from cutting each other’s throats. Is it me or is this starting to feel like an unusually busy week?”
“Look on the bright side,” Dreyfus said.
“Thalia’s going to be done soon: that’ll be one case closed. And we’re making solid progress on the Ruskin-Sartorious investigation.” He studied Sparver with sudden intensity.
“We are, aren’t we? Or did you just drop in for tea and sympathy?”
“Tea. For sympathy I go elsewhere. Mind if I use your wall? I want to show you what I got from the router.”
Dreyfus extended a hand.
“Go ahead. It’s group-conjurable.”
With the slightly exaggerated patience Dreyfus had sometimes come to recognise in his underlings,
Sparver walked him through the data. There were five columns of information: the time of arrival of an incoming transmission, its point of origin (the next node up the line), its intended destination (the next node down the line), the time when it had been forwarded—typically only a few nanoseconds after it had come in—and a final column giving some sketchy information concerning the contents of the transmission.
“There’s a lot of CTC traffic coming through,” Sparver said, indicating a proportion of columns with a particular flag in the fifth column.
“That we can dispense with. It’s just navigational housekeeping data, keeping tabs on all the ships and drones moving through the Band.” Sparver removed the CTC data, leaving many blank lines in the wall display. Dreyfus felt cheered: they were getting somewhere. But his glad frame of mind didn’t last long. The remaining data shuffled up to fill the gaps, leaving the wall looking much as it had before. He reminded himself that he was only seeing a small, illustrative portion of the entire router log, and that there were millions of lines above and below the visible segment.
“Now we do a similar filtering on polling traffic,” Sparver said.
“That takes care of another major chunk of the data. Run the same trick on traffic on the major trade nets and we delete another big chunk. It may not look like an improvement, but we’ve already shrunk the log by about half. But we can do better still. Clear out all router housekeeping and we drop another ten per cent. Clear out standard abstraction packets and we’re down to about twenty per cent of our original file.”
It must still have been tens of thousands of lines.
“We’ll need to do better than that, even,” Dreyfus said.
“And we can. Now we filter on the target address of Ruskin-Sartorious.” Sparver scrolled up and down to show that he had now reduced the log to a mere thousand lines or so.
Dreyfus scratched at his left eyebrow.
“Why didn’t we just jump to this point in the first place?”
“Doesn’t work like that,” Sparver said.
“Like almost every habitat in the Glitter Band, Ruskin-Sartorious would have handled onward forwarding of third-party data, including CTC services, trade talk, abstraction packets, the works. We’d still have had to strip all that from the list even if we narrowed it down to messages only going to Ruskin-Sartorious.”
“Would have been faster, though.”
“But logically equivalent. The system doesn’t care in which order you do the filtering.”
“I’ll take your word for it. But we’re still looking at a mass of data.”
“We’re not done. Now we start getting clever.”
“I thought we were already being clever.”
“Not enough.” Sparver smiled—he was clearly enjoying himself.
“See that number in the fourth column?”
“Yes,” Dreyfus said guardedly.
“Timetag for outgoing transmission.”
“That’s our clue. The message that came through to Ruskin-Sartorious was voice-only, right?”
“According to Vernon and Delphine. What difference does the message format make?”
Sparver drank from his cup.
“It makes a world of difference. When a transmission goes through the router, it’s subjected to a certain amount of routine processing. Cyclic redundancy error-checking, that kind of thing. If there’s a fault, the router sends a message back to the previous sender, asking for a
repeat transmission.” Dreyfus nodded provisionally.
“Makes sense.”
“The point is, all that error-checking takes a finite amount of time. And the heavier the data burden—the more content there is in the message—the more number-crunching needs to be done.”
“Ah. I think I see where you’re going.”