Re: latest Snowden docs show NSA intercepts all Google and Yahoo DC-to-DC traffic

[Matthew Petach <mpetach () netflight com>]

On Thu, Oct 31, 2013 at 5:53 PM, Jimmy Hess <mysidia () gmail com> wrote:

> On Thu, Oct 31, 2013 at 7:24 PM, Matthew Petach <mpetach () netflight com>wrote:
>
> > On Thu, Oct 31, 2013 at 7:02 AM, Ray Soucy <rps () maine edu> wrote:
> > > Was the unplanned L3 DF maintenance that took place on Tuesday a frantic
> > > removal of taps? :-)
> No need for intrusive techniques such as direct taps:
> > http://ieeexplore.ieee.org/xpl/articleDetails.jsp?reload=true&arnumber=1494884
>
> For shame.... you've  sent in a link to some article behind a paywall,
> with some insane download fee.
> Which is an equivalent of hand-waving.
>
> They must be hiding their content,  for fear that flaws be pointed out.

Oy...OK, let me find a document that spells it out
a bit more clearly for you.


> "Of all the techniques, the bent fiber tap is the most easily deployed with
> > minimal risk of damage or detection. The paper quantifies the bend loss
> > required to
> > tap a signal propagating in a single mode fiber"
>
> There will be some wavelengths of light, that may be on the cable, that
> bending won't get a useful signal from.
>
> Bending the cable sufficiently to  break  the total internal reflection
>  property,  and allow light to leak --  will generate power losses in the
> cable,  that can be identified  on an OTDR.

This patent covers a technique developed to do
non-intrusive optical tapping with a 0.5" microbend,
with only 0.5dB signal loss:

http://www.google.com/patents/CA2576969C

Most people aren't going to be able to tell a
0.5dB loss from a microbend tap from a splice
job.

Matt



> > Matt
> --
> -JH