NSA tapping undersea fibers?

Tib tib at tigerknight.org
Tue May 29 00:46:59 EDT 2001

I'm curious as well about how the tap could actually happen though without
some major bells and whistles taking place. If my understanding of fiber is
correct, data flows at incredible rates through a line - but one fracture and
suddenly you're going to have massive data loss and I can imagine that at the
controlling house for that fiber line all manner of noise is going to happen,
which would also (another guess) cause events to roll into place where a repair
team would be sent out ASAP to check on the fiber and fix it - in which case
the people trying to install the tap would be caught red handed? I don't have
the manual handy on how they manage trans oceanic fiber lines, and I know there
are a few for redundancy so that they might not fly/swim out there immediately
for repairs. It would also be incredibly fishy to any operator who saw a line
go down and then come backup when both sides report that all physically
immediately inspectable connections are otherwise normal and good? Hate to be
cliche in this thought but if this happened about the only way I can see this
taking place (from the limited knowledge I have on this) would be if there was
an NSA or other government agent standing over the operator as the alarm went
off about the line failure and canceling it, then politely telling the operator
'This never happened, and I was never here' (a'la James Earl Jones in Hunt for
Red October).

To sum this whole thing up - /IS/ there a way to put a tap on a fiber line
without letting the whole world know you're doing it, if not just the
operator/owner of the line itself? And if so could someone sketch it out for
me or point me to a resource? I'd love to learn of it


On Sun, 27 May 2001, Dave Emery wrote:

> On Wed, May 23, 2001 at 04:08:34PM -0700, Steve Bellovin wrote:
> > There's a long, fascinating article in the 23 May Wall Street Journal
> > on how NSA is (allegedly) tapping undersea fiber optic cables.  It's
> > not clear that this is feasible, but the article claims that the
> > USS Jimmy Carter, a nuclear-powered sub, is undergoing a $1 billion,
> > five-year retrofit to equip it to do the taps.  The article points out
> > that even if they can tap the cable, there's another problem: making
> > sense of that much data.
> 	I think the later argument is just as disengenuous as the late
> 60's Bell System officials who said exactly the same thing about the
> open unencrypted microwave radio telephone links of that era.   Both
> those microwave links and the undersea fibers contain highly structured
> and organized information streams - individual voice channels, T1s, T3s,
> IP streams, wideband data circuits are not at all difficult to extract
> from the composite traffic and mapping the layout of the whole river of
> information is by no means overwhelmingly difficult (and might be aided
> by quiet help from the carriers or individual employees of the
> carriers).  And the mapping tends to be pretty static over time, or at
> least to change in predictable ways.  Finding and recording the most
> interesting circuits is by no means an insurmountable task - nor is
> filtering out most of the stuff that isn't interesting.   The only hard
> problem is if the NSA insists on groveling through absolutely everything
> sent, but this is true of their problem in general these days and not
> just special to undersea cables.   And clearly the right undersea cables
> contain an awful lot of useful stuff if you are the NSA...
> 	And given modern high capacity digital storage systems, handling
> low gigabytes a second is not that difficult either (most current
> undersea cable systems only transmit between 2.5 and 20 gigabits a
> second or so).   IO bandwidths in large fast servers are of this order
> or more these days...
> 	The much more interesting problem that gets rather short shrift
> in the WSJ article is how the real time time critical intercepts get
> from a submarine hiding in stealth 1200 feet under the ocean to Fort
> Meade and then to policy makers.  Some fraction of the traffic is still
> interesting after weeks or months when tapes or disks can be flown back
> to Fort Meade but much more of it is only useful if it is available
> within seconds or minutes during a crisis and not weeks or months later.
>   Traditional microwave radio and satellite intercepts get back to Fort
> Meade or the RSOCs in milliseconds but as more and more traffic flows
> through cables that can only be tapped by hiding billion dollar nuclear
> submarines a lot of the timeliness of NSA operations goes away.
> 	The IVY BELLS tap technology exmplyed against Soviet analog
> undersea cables in the 70s allegedly involved hooking up a nuclear
> radioisotope powered pod with tape recorders in it that was left in
> place for almost a year between submarine visits to recover the tapes -
> this would be rather hard to do with the gigabytes per second flowing
> through a modern fiber cable - there is no (unclassified) recording
> technology with anything like the storage capacity to record everything
> or even a significant fraction of everything for that long a period in a
> form factor that would fit in a pod on the sea floor.
> 	According to published accounts, in the early Reagan years the
> intelligence community considered  running their own fiber cable to the
> tap site on the Soviet analog cables to recover the data in real time -
> I imagine that the same thing has been considered as a solution to the
> current problem of recovering data from undersea fiber taps while it
> is still fresh enough to be useful.  But in general it is a harder problem
> than actually tapping the cable or dealing with the rivers of data it
> contains.

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