On 6/13/07, Tyler Durden <camera_lumina@hotmail.com> wrote:
First of all, anyone have the latest word about Cryptome?
what?
Second of all, I took a look at these and what's becomming quite clear is that they don't really say that much. They basically just show how the LGXs are connected and interface into and out of the "secret room" via splitters.* It does say that a buttload of traffic is being split and sent off to NSA equipmet ...
right. tap all the interesting fibers, feed to narus.
but the real missing piece is just how that traffic gets back to NSA. I still believe that they just can't send back EVERYTHING, and have to have several layers of prioritzation, so that only fairly interesting traffic makes it back in real time (this is not to say that they don't possibly route and store uninteresting local traffic for future reference) but they can't get everything back to, for instance, DC in real time.
the narus is there specifically so they don't have to backhaul a mirror of the traffic. it does all the inspection to isolate interesting information, then sends back that interesting information to aggregation points, before that in turn is sent on to NSA. the bridgeton center att noc is a good example. there is a room controlled by multi-factor biometric authentication (print, retinal) with man trap doors. this is probably the room used for distributing configuration to the remote monitoring points (it's unlikely they store much of interest at the remote sites, since the security is much lower at these places) as well as aggregation of the feeds for backhaul to NSA. see also the new NSA facilities being built in denver, CO. this is an ideal place to aggregate traffic across the country...
Another question I've had for a while is how they get around the loss budgets in certain cases. Dropping a 3dB splitter into an OC-48 signal that's pushed to the limit will result in some signficant BER degredation. Do they just avoid those signals? DO they put in some kind of in-line optical amplifier? (That's not trivial, as they have to electrically power such a device.)
from the sounds of it, the taps did introduce some problems which were resolved quickly. probably not from signal loss, but who knows. in any case, i don't think powering an optical amplifier is difficult in the facilities in question. for transoceanic cables it becomes a bigger problem :) best regards,