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"It's not just a US problem. The UK has a huge dog in this fight," Snowden told the Guardian. "They [GCHQ] are worse than the US." I'm not sure if I've got the

"It's not just a US problem. The UK has a huge dog in this fight," Snowden told the Guardian. "They [GCHQ] are worse than the US." I'm not sure if I've got the picture right. Someone more informed than I please help. First, let us set the scene with a precedent - the famous WWI Zimmermann Telegram of 1917 where Germany and Mexico were concocting a secret deal that wasn't in the interests of the US or UK which was tapped and successfully intercepted: https://en.m.wikipedia.org/wiki/Zimmermann_Telegram https://en.m.wikipedia.org/wiki/Zimmermann_Telegram. I only mention this 100-year-plus case as it'd be at the forefront of any planning for any undersea cable, transatlantic otherwise to see such incidents are not repeated. OK, so where are my assumptions wrong here? 1. Cable operator of say US-UK link doesn't want a tap put on cable in mid Atlantic by a third country so takes the necessary steps by encrypting all its data. 2. Cable operator knows both US/NSA and UK/GCHQ will want to tap cable at their respective ends (i. e.: on land). No problem, as the cable operator has no say in the matter anyway. 3. To stop undersea tapping by third party, cable is encrypted at cable stations at either end. Multiple levels of encryption are employed: fibers are encrypted either individually or collectively so only a raw encrypted datastream appears on the undersea section of circuit; that is, the only discernible IP address information on the cables is that necessary for the cable stations at either end to TX/RX data across the Atlantic. Thus an attack in the middle won't reveal who is using the cables nor their IP addresses (as they too will be encrypted as part of the overall encrypted datasteam). 4. Third-party counties, for argument sake, say Mexico and Germany that are also using the cable will similarly encrypt and obfuscate the source and destination IP addresses of all their users in a similar manner using an all-encompassing encrypted datastream. So effectively the NSA and GCHQ can only inspect their own local traffic, which they do on land at their respective cable stations after the undersea section of the link has been decrypted. 5. As, we've made Mexico and Germany the adversaries, we can expect them to not only encrypt data and obfuscate source and destination IP addresses of their users by multiplexing all data into a common encrypted datastream but also obfuscate the amount of traffic they're sending. They will likely achieve this obfuscation by using say an encrypted token ring/FDDI-like system, then the datastream would appear to be a constant quantity irrespective of the actual circuit load. 6. In essence, why do countries still try to tap undersea cables with submarine taps when they'd only pick up encrypted 'garbage'? Alternatively, why do cable users leave themselves vulnerable to tapping when they could employ methods to obfuscate not only their data but also how they are loading (using) said cables? Right, I've greatly oversimplified the issue but the gist of my point is there.

sneak 5y ago
Encryption at these data rates was only recently within the realm of feasibility (wrt cost). You can always encrypt traffic that needs it at higher layers; most of these sorts of links were not themselves bulk encrypted. MUSCULAR, for example, allowed the spies to tap WAN links between Google sites, which were at the time unencrypted as it was only Google-internal, even though it went hundreds of miles out of the buildings. Those links are encrypted now. Google SREs were not happy about being hacked by the NSA. I was told by SREs that they weren't encrypted before due to the CPU overhead that it would entail, as Google moves a lot of data. Once the threat wasn't theoretical, they were encrypted quickly.
- hilbert42 5y ago
  "You can always encrypt traffic that needs it at higher layers; most of these sorts of links were not themselves bulk encrypted." I'm surprised that encryption wasn't (still isn't) the default for all submarine cables given the very high stakes involed - international espionage, their vulnerability and the long history of undersea cable tapping (which I didn't mention above). You say "Encryption at these data rates was only recently within the realm of feasibility". Right, but 'recently' has been quite a while now - I'd estimate 10-20 years or so as we've had erbium optical switches, etc., in common use for that length of time. It's now over 25 years since I was first involved in some high-stakes intergovernmental stuff where authentication and encryption were the normal default thinking (it was inconceivable that we'd transmit data across any link or network that was potentially vulnerable to attack unless the data was encrypted and full authentication was deployed). We used common carrier networks and submarine cables would have to have been involved but we did not administer them - hence our assumption that they were vulnerable to attack. Whilst I wasn't involved directly with those security services, it was clear to me that at the time they didn't want encrypted circuits. Thus, it seems likely that at least part of the reason for the lack encryption even now would have been pressure from them not to deploy it in common-carrier networks.
  - sneak 5y ago
    It isn't very high stakes, as all the important stuff is already encrypted at higher layers (TLS, VPNs, or both) before it hits the cable, whether the submarine cable is encrypted or not. Only private industry was pretending long haul cables were reasonably private, and even they aren't making that mistake anymore.

sneak 5y ago

Encryption at these data rates was only recently within the realm of feasibility (wrt cost). You can always encrypt traffic that needs it at higher layers; most of these sorts of links were not themselves bulk encrypted. MUSCULAR, for example, allowed the spies to tap WAN links between Google sites, which were at the time unencrypted as it was only Google-internal, even though it went hundreds of miles out of the buildings. Those links are encrypted now. Google SREs were not happy about being hacked by the NSA. I was told by SREs that they weren't encrypted before due to the CPU overhead that it would entail, as Google moves a lot of data. Once the threat wasn't theoretical, they were encrypted quickly.

hilbert42 5y ago
"You can always encrypt traffic that needs it at higher layers; most of these sorts of links were not themselves bulk encrypted." I'm surprised that encryption wasn't (still isn't) the default for all submarine cables given the very high stakes involed - international espionage, their vulnerability and the long history of undersea cable tapping (which I didn't mention above). You say "Encryption at these data rates was only recently within the realm of feasibility". Right, but 'recently' has been quite a while now - I'd estimate 10-20 years or so as we've had erbium optical switches, etc., in common use for that length of time. It's now over 25 years since I was first involved in some high-stakes intergovernmental stuff where authentication and encryption were the normal default thinking (it was inconceivable that we'd transmit data across any link or network that was potentially vulnerable to attack unless the data was encrypted and full authentication was deployed). We used common carrier networks and submarine cables would have to have been involved but we did not administer them - hence our assumption that they were vulnerable to attack. Whilst I wasn't involved directly with those security services, it was clear to me that at the time they didn't want encrypted circuits. Thus, it seems likely that at least part of the reason for the lack encryption even now would have been pressure from them not to deploy it in common-carrier networks.
- sneak 5y ago
  It isn't very high stakes, as all the important stuff is already encrypted at higher layers (TLS, VPNs, or both) before it hits the cable, whether the submarine cable is encrypted or not. Only private industry was pretending long haul cables were reasonably private, and even they aren't making that mistake anymore.