"Cory Doctorow - Liberation Spectrum" - читать интересную книгу автора (Dodd Christina)

Elaine gave Lee-Daniel a look, then ran the dot of her pointer over each of
the strategic areas again. Some of the surveyors groaned and whispered to the
antennamen and the switchgirls.

Lee-Daniel cleared his throat. "Meatloaf," he said, "all respect, but well,
this won't work. Our radios operate on line of sight. If we can see it, we can
shoot it at half a gigabit a second -- slower if there are a lot of leaves and
stuff in the way. If we can't see it, we can't shoot it. Zero bits per second.
We need high ground, we need perimeter, otherwise we're just wasting your
time."

Meatloaf shook his head. "Radio radiates. I can't see the cell tower, but I
can still reach it with my phone."

"That's dumb radio," Lee-Daniel said. "If we want to have a conversation and
we're out of sight of one another, we can communicate, but only if we shout.
That's fine for us, but it's not so good for the people between us, right,
Mortimer?"

Mortimer, who'd been through one or two (hundred) of these demos before, took
his cue from outside the doorway, hitting it with the loudhailer dialed up
about half way. "Right," he said.

"That's how dumb radio works. You had a bunch of bands that you could
communicate in -- cellular, TV, AM, FM, cops, air traffic, whatever -- and
rules and licenses for each, governing how loud everyone gets to shout."
Taking their cues, the CogRads started to gabble all at once, in stripes
through the ranked chairs, saying "AM AM AM" or "TV TV TV" or "cellular
cellular cellular."

"Smart radio -- cognitive radio -- is much more clever. Instead of shouting
loud enough to be heard across the entire distance, cognitive radios cooperate
with one another. When I need to talk to Mortimer, I first check around to see
what channels are least occupied and most close to me, then I send my message
to the best candidate." He turned to Elaine, who'd come to stand by his
shoulder. "Tell Mortimer that it's time to come back," he said.
Elaine turned to a switchgirl who'd positioned herself a few feet away and
said, "Tell Mortimer it's time to come back," she said.

The switchgirl turned, but the next person in the chain, a customer service
rep, had his phone headset in and was having a hushed support call -- it was
faked, just part of the script, but he gave a good impression of helping
someone tech a network problem at a distance, tracking a nonexistent support
script across his HUD and prodding at the air with a dataglove.

"Aha," Lee-Daniel said, "here's where it gets tricky. What if one of the
radios between us is too busy to relay a message? We've got two options. We
can wait -- which we'll do if we have to, but it adds latency to the message
-- or we can find an alternate path."