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>I'd also like to have them publish and guarantee exactly what they mean by "encrypted to the PSTN"

If you look at the infographic from the article you'll see that if it's not end-to-end then it's only to their servers. The crypto will flow from Caller<->Callee or Caller<->Server. I think it's safe to assume that their server then connects to the PSTN, hence "encrypted to the PSTN."

Precisely. The PSTN leg is routed via iBasis.

http://www.broadwayworld.com/bwwgeeks/article/Silent-Circle-...

Disclaimer that I feel like I repeat too often but is probably still warranted: I am a Silent Circle employee.

I wonder if it would be better opsec for security oriented companies to have policies that encourage employees not to reveal their employer. You have 3000+ karma with a significant posting history, which I think translates into an increased surface area for social engineering attacks.

The more someone knows about you the more they could either find a way through you into the company, and eventually on to the servers.

Like for instance you might reveal something in your posts that could be used to find out more about you online and eventually get access to your amazon account, or paypal account, or your gmail account and use this to get access to your work email or enough information to impersonate you or impersonate someone who pretends to know you, until eventually they get in and find access to things Silent Circle doesn't want people to access.

Relevant: http://xkcd.com/538/

As with many things in life, it's a tradeoff... Does it help someone who is conducting recon on Silent Circle employees? Absolutely. But by the same token, we feel the fact that we do have employees who are active parts of communities like this is an asset. For that matter, communities like HN are a great asset to companies like us (we've had great success with the Who's Hiring threads).

It wouldn't take much for someone to sort out my HN profile regardless of my disclaimer though. My HN username is the same as my GitHub username, which is linked to the Silent Circle organization.

If you have private repos on GitHub, and lets say GitHub has a security vulnerability[1] that lets users post to private repos it probably would be better if malicious people who knew that their target used Silent Circle didn't know you were on GitHub. Which I didn't, until you just mentioned it. Why are you on GitHub?

[1] http://arstechnica.com/business/2012/03/hacker-commandeers-g...

We don't host any private repos at GitHub.

I'm on GitHub because we release the sources of our clients and because we use several open source libraries in our stack and it's very impractical to push changes upstream if you don't have a GitHub account.

I could certainly do that anonymously, but again... tradeoffs. It's more convenient for me to do it from my primary account (which makes me more likely to do it) and there are advantages to publicly sharing that we give back to projects that we use.

Do you think someone doing a recon on a target like a developer at Silent Circle _wouldn't_ check for a GitHub profile?

EDIT: Dunno who is downvoting you. You raise very valid points (ones that we have had many conversations about), and have been very cordial...

1.) Security theater. The hypothetical competent attacker already knows who works for Silent Circle, from any one of a dozen different public sources. No company that actually accepts money from customers can be stealth enough.

2.) Mere access to a security company's internal network isn't as useful as it would be for, example, a credit card processor's internal network. (Except for stealing secret keys, etc) The more serious threat is not intrusion, but tampering. (Pretending to be a employee for sneaky NSA-style RNG-weakening, etc) Covert tampering is a heck of a lot harder.

So you IPSec to iBasis and then what? Or do you have servers colo'd remotely with iBasis and the client has those keys in the app? Because Skype uses iBasis too, so I'm failing to see a difference.

Also, how is iBasis the PSTN? They do quite a bit of IP handoff (and IIRC there were a big fan of the laughably insecure NexTone platform). Are they providing you a product where they encrypt their traffic on their own network and ensure local TDM handoff in every country? (And even then, it's surprising how much stuff ends back up on IP.)

The claim of "encrypted-to-the-PSTN" sounds either slightly far-fetched or defined in a useless way.

(I'm all for Silent Circle, but this PR comes off very wrong.)

The client does a ZRTP handshake with a media relay which sets up the PSTN call. We are adding POPs depending on traffic in order to get that ZRTP termination as close as we can to common destinations, ideally minimizing as many border crossings as possible (as that is, at least theoretically, where the greatest risk of interception exists).

The goal of PSTN calling isn't to provide bulletproof security. The goal is to provide a somewhat reduced exposure, and to allow you to use the app as your default dialer, hopefully making it a habit. If you need your conversation to be very secure, then both parties should be using the app (and hopefully you're both in the habit of using it anyway, since you can make your PSTN calls there as well).

I've been trying to get in touch with your CEO - could you be of help? @simon on Twitter, you find my email there. Thanks :)

I'm <my first name>@silentcircle.com, where my first name is 'josh'. Feel free to shoot me an email and I can pass you along to Mike.

>Not to mention, encrypted to the PSTN solves what, exactly?

I presume, if one calls Germany, and the line is encrypted from the handset to Germany, then that person would be out of NSA's reach.

I suspect that would make wiretaps more difficult as well, since police would need to tap who is called, instead of the caller. That's a lot more warrants and they need them in advance of a call... or they need every call recorded from the end points for later search.

> I presume, if one calls Germany, and the line is encrypted from the handset to Germany, then that person would be out of NSA's reach.

I would not make that assumption. While I have no evidence, there are plenty of ways the NSA could collect data along these paths - exploiting bugs in the switches, installing a beam splitter in fiber as it traverses a remote area, etc. etc.

Seems like a bad assumption to make.

When Germany caught the U.S. spy recently, it was based on that German worker using a personal GMail account to email the Russian consulate.

That email was magically intercepted by Germany's BND somehow, in what I'm sure has nothing at all to do with any sort of network surveillance measures in Germany targeting foreign intelligence.

But just to be safe we should probably assume that BND is actually listening within Germany, just like the U.S. spy should have assumed BND could read his email.

But the PSTN is the easy part to wiretap. Especially the TDM part of it. Data is nicely partitioned in channels and there is only one single metadata format to worry about.

And you can not compare the NSA with the police. The latter needs a warrant (sort of, depending on locale) but the former doesn't.

According to everything I've read on the subject, including today's revelation that NSA is recording 80% of all phone calls, is that NSA grabs from the backbone. They do not have monitoring installed at endpoints. That would be expensive, and in foreign countries, infeasible. It's hardly perfect, but I think everyone can agree it's better than unencrypted all the way. Everyone except the Friends of NSA trying to convince everyone to stay away, because "it isn't truly secure"... You've got to start somewhere.

That's what I'm saying. The "backbone", by which I take it you mean the big PSTN providers, is by far the easiest point to wiretap. Internet exchange points are by design far more heterogenous, plus that wirespeed protocol parsers that has the ability to parse the plurality of protocols used is at least an order of magnitude more difficult/expensive.

The five eyes do that as well, no doubt about it. But if you encrypt your traffic on IP and then switch out to unencrypted PSTN then that's completely useless as you'd risk drawing unnecessary attention to your plaintext.

>But if you encrypt your traffic on IP and then switch out to unencrypted PSTN then that's completely useless as you'd risk drawing unnecessary attention to your plaintext.

So the solution you suggest is to try to hide in plain sight? Good luck with that.

Why would you think that? Am I really that unclear?

If I had to venture a suggestion it would be to encrypt your data end-to-end.

lol. Right, because my mom's rotary phone will work like that.

That's the "comprehensive reform" argument weaselly politicians use. Ex. Chuck Schumer works for the banking industry. The banking industry needs reform after financial crisis. Chuck blocks banking reform by demanding "comprehensive reform" and refuses to implement partial measures that would help/start the reform process. He claims he's strongly in favor of reform. So much he's unwilling to compromise for partial measures. As such, he votes against all measures of reform. Sure Chuck, we all believe you really want to reform the banks that paid for your elections.

If end to PSTN can make it more expensive for the NSA to collect, then it's good, even if it isn't foolproof.

If the default config for apache were to generate self signed certificates, you would say, that's useless, because MITM. I would say, that's great, because now NSA is forced to MITM if they want to snoop. It increases the expense for the attacker, making their ability to snoop more limited.

> Right, because my mom's rotary phone will work like that.

No it doesn't. That's why you shouldn't market products with the claim to make secure calls to her.

There are product to encrypt PSTN calls. These products needs to be used at both ends to be effective.

> If end to PSTN can make it more expensive for the NSA to collect, then it's good,

It doesn't, that's the point. You can count on the whole SS7 being compromised, all the time. It's where these agencies came from.

> If the default config for apache were to generate self signed certificates, you would say, that's useless, because MITM.

Again words in my mouth. I believe it is in fact the default in the major distributions, and it isn't "useless". This has absolutely nothing to do with the PSTN so I won't discuss this particular straw man further.

>I believe it is in fact the default in the major distributions

I have never once seen apache generate a self signed cert and default to http off for all connections. But sure, you didn't say that. I was simply drawing a parallel argument to what you were saying about PSTNs.

So let me make one more logical fallacy since the article clearly isn't providing enough info to prove either of our arguments.

Appeal to authority: Who should I trust dude? You, random internet poster, or Phil Zimmermann? I'm going with the guy who invented PGP and has a reputation and track record on encryption. Through his actions, he has built lots of trust/cred. You have not. If he has started a company, is delivering this as a product, and marketing that aspect as a feature, he clearly believes that it offers some benefit over a fully unencrypted line.

I'm willing to give that man the benefit of the doubt. You on the other hand could be working for the NSA and trying to derail interest in his product for all I know. Oops, that was two logical fallacies.

It's ridiculously slimy. For the countries I've looked at, their 100 minute a month plan works out to be more than five times as expensive per minute as Skype's pay-as-you-go call prices where you just pay for what you use with no monthly charge.

They're probably funded through the black budget, so can play the field.

I for one have zero confidence that this isn't an elaborate honeypot, as anyone interested in privacy is a target, and this would seem an excellent way of gathering more innocent people to target with surveillance.

100 minutes for VOIP calling, not regular data calling. Last I checked Skype charged for those, too.

That's still outrageously overpriced, like everything else they sell. VOIP calls are pennies per minute with every other VOIP provider.

100 minutes of outbound. Inbound is free.

I read it as 100 minutes to the PSTN - VoIP to normal phones. Skype has "unlimited" for $13 to several countries. That's because for the US, the average price is well under a penny, and for Canada it's a few tenths of a penny/minute. Many other countries also have fairly cheap rates.

So I'm confused as to why he'd compare a $12 100 minute plan to a $13 "unlimited" plan.