3 ms·

I don't have any traceroutes so this is speculation but the probably just route around it if it only takes 30 minutes. I was under the impression that a beam s

I don't have any traceroutes so this is speculation but the probably just route around it if it only takes 30 minutes. I was under the impression that a beam splitter can be installed without disruption. If they fucked up and broke the cable installing a beam splitter, a 30 minute fix is still pretty impressive.

rmetzler 7y ago
I‘m by no means an expert but I did some datacenter work. I wonder how this would be possible to install a beam splitter without disruption? Don’t you need to plug the fibers out, put the splitter in and then plug the fibers back in the splitter? I was searching YouTube but couldn’t find a video.
- Hikikomori 7y ago
  You don't need a beam splitter to listen in on traffic.
- xvilka 7y ago
  They bend the cables, thus allowing part of it be tracked with some residue light coming out of the fibre.
  - rmetzler 7y ago
    I agree, this might be possible but I wonder how good the quality is then? A splitter will give you 50% light. That limits the length of the cable too, doesn’t it? How many errors will be there when you bend the cable and get maybe 15% light of encrypted traffic, and you can’t signal any retransmission?
    - Kubuxu 7y ago
      On run of the mill singlemode fiber loss is roughly 0.5dB/km. Splitting off half of the light (and you don't need half, much less is fine), would result in 3dB of loss. Fiber tramsreceivers automatically negotiate the power needed to sustain the link. So in case of datacenter or city networker, you could do a split-of without introducing too much loss and error rates. Trans-oceanic fibers are different beast but I guess someone figured it out.
- anonymfus 7y ago
  The light is kept inside the fiber by the change in refraction index in the radial direction of the fiber so there is a total internal reflection. But if you bend the fiber enough then reflection is not total and part of the beam goes outside.

rmetzler 7y ago

I‘m by no means an expert but I did some datacenter work. I wonder how this would be possible to install a beam splitter without disruption? Don’t you need to plug the fibers out, put the splitter in and then plug the fibers back in the splitter? I was searching YouTube but couldn’t find a video.

Hikikomori 7y ago
You don't need a beam splitter to listen in on traffic.
xvilka 7y ago
They bend the cables, thus allowing part of it be tracked with some residue light coming out of the fibre.
- rmetzler 7y ago
  I agree, this might be possible but I wonder how good the quality is then? A splitter will give you 50% light. That limits the length of the cable too, doesn’t it? How many errors will be there when you bend the cable and get maybe 15% light of encrypted traffic, and you can’t signal any retransmission?
  - Kubuxu 7y ago
    On run of the mill singlemode fiber loss is roughly 0.5dB/km. Splitting off half of the light (and you don't need half, much less is fine), would result in 3dB of loss. Fiber tramsreceivers automatically negotiate the power needed to sustain the link. So in case of datacenter or city networker, you could do a split-of without introducing too much loss and error rates. Trans-oceanic fibers are different beast but I guess someone figured it out.
anonymfus 7y ago
The light is kept inside the fiber by the change in refraction index in the radial direction of the fiber so there is a total internal reflection. But if you bend the fiber enough then reflection is not total and part of the beam goes outside.