NSA tapping undersea fibers?

John Denker jsd at research.att.com
Sat Jun 2 01:21:32 EDT 2001


I wrote:
> > First, it should be obvious that They don't need a submarine to tap cables
> > that already make landfall in the US, which is the vast majority:

Then at 07:33 PM 6/1/01 +0100, Peter Fairbrother wrote:

>Of course they have reasons to want to
>tap cables that make landfall in the US.

1) I assume when this says "tap" it refers to undersea tapping;  that 
wasn't obvious on first reading, which caused some confusion.

In any case, I stand by my assertion that dry-land tapping is more 
plausible than undersea tapping of these cables.  I am unconvinced by the 
counterarguments that were advanced:

>Apart from the legal aspects, eg operations conducted outside the US,

2) I don't know what this means.  A legal tap is legal onshore or 
offshore.  An illegal tap is illegal onshore or offshore.  US law makes no 
distinction.

>"inadvertant" monitoring of  US citizens,

3) The law doesn't require it to be inadvertent, just "minimized"
        http://www4.law.cornell.edu/uscode/unframed/50/1802.html
...and the law defines a pretty broad minimum!
        http://www4.law.cornell.edu/uscode/unframed/50/1801.html

>and the frankly illegal things they might want to do,

I don't know what this means.  See item (2) above.

>NSA aren't going to trust cable operators to keep wholesale monitoring secret.

It's no secret that you-know-who can _legally_ tap the cables (subject to 
the "minimization" requirements).  A lot of things that were done illegally 
in the 1960s and 1970s are now legal, and indeed mandatory, under the 1978 
law.  (Whether they violate the 4th amendment is a more subtle question.)

Cable operators can be directed to "furnish all information, facilities, or 
technical assistance necessary to accomplish the electronic surveillance in 
such a manner as will protect its secrecy...."
        http://www4.law.cornell.edu/uscode/unframed/50/1802.html

The cable operators are going to comply with all surveillance 
directives.  Noncompliance would carry a $10,000 per day "civil" penalty.
        http://www4.law.cornell.edu/uscode/unframed/18/2522.html

Revealing classified information "concerning communications intelligence 
activities of the United States or any foreign government" would be a 
felony, so don't expect the operators to give you a tour of the place where 
the spooky feed splits off from the transoceanic feed.
        http://www4.law.cornell.edu/uscode/unframed/18/798.html


==============

As a general rule, if you are standing in the middle of a cattle ranch and 
you hear hoofbeats, don't look around for zebras -- it's probably just 
cattle.  Undersea cable-tapping seems to me to be a bit of an imaginary 
zebra.  It's implausible when the same cable could be tapped onshore.

OTOH, as I pointed out before, there are certain places where real zebras 
can be found.  Africa is an example.  Why do you think AfricaONE has a 
backbone that circles the continent offshore, plus separate drops for each 
country, when it would have been vastly cheaper to go by 
land?  Answer:  everybody thought that an offshore cable would be less 
likely to be tapped by hostile powers.  (Each country can of course tap its 
own drop, along the lines discussed above, but it can't so easily tap other 
folks' signals on the backbone.)

>I speculate that the NSA could (and probably do) lease fibres from cable
>companies. I also expect that if they wanted to install their own monitoring
>equipment and security at the cable termination site, no-one would raise an
>eyebrow.

Given that AfricaONE is spending hundreds of millions of dollars to prevent 
tapping, I think quite a few eyebrows would be raised if they leased fiber 
and other facilities without ironclad assurances that they wouldn't be used 
for snooping.

And I imagine the AfricaONE operators are clever enough to check that all 
packets that come out correspond to packets that went in, so that their 
cable can't be used as backhaul for anybody's tap.

So I still think that backhaul is an interesting challenge for anybody who 
wants to operate undersea taps.  There are ways to do it, but no super-easy 
ways.

================

Some interesting info about the structure and function of the USS Jimmy Carter:
   http://www.chinfo.navy.mil/navpalib/cno/n87/usw/issue_5/ussjimmycarter.html




---------------------------------------------------------------------
The Cryptography Mailing List
Unsubscribe by sending "unsubscribe cryptography" to majordomo at wasabisystems.com




More information about the cryptography mailing list