Ask HN: Why is PGP not used widely?

The ease of use has to approach at least Skype level (and even then you'll exclude a wide swath of users who don't know how Skype works).

There's an old joke about Unix to the effect of "it's not user unfriendly; it's actively user hostile". Likewise, many aspects of PGP, E.G. key generation and management, web of trust, public key validation and keeping the private key secure that is utterly befuddling for the vast majority of people. This, despite the fact that it's one of the most accessible avenues for secure communication we have right now.

If people have things that are easier to use securely, more people will be secure.

I think it's because there still isn't a good metaphor that covers up the complexity of public key encryption. Such a metaphor is a prerequisite for a UI that the average user can comprehend.

First, I think we should rename the keys to 'locking key' and 'unlocking key'. I've had people still scratch their heads at 'public/private' a few days after I've completely explained the concept to them. They find it easier to understand that a lock-only key can be shared freely while an unlocking key has to be guarded.

Second, key exchange and storage has to be transparent to the user. The process can go something like:

1. User 1 clicks 'setup secure email with user2@domain.com'

2. User 2 receives 'user1@domain.com wants to setup secure email with you. y/n? (first make sure that this is really his/her email address)'

3. Based on the response, keys are automatically exchanged and stored.

4. Provide a 'compose secure email' option

5. When adding email recipients, the encryption happens automatically. Recipients with no keys are not allowed in secure mail, obviously.

6. The encrypted form is never displayed on screen. Only a lock icon.

7. On the receive end, a passphrase prompt is displayed when a secure mail is opened

Perhaps commercial/proprietary clients already do this, but none of the free ones I've tried are like this. So I'm stuck with using GPG with only with those who understand how the thing really works.

Even if you know what you are doing and really must get some secure document to someone then it is far from straightforward. First you need to get the key. Then you need to get that key onto a computer that you believe is not already compromised. Anything running Windows can be assumed to be less than secure. Whatever happens there will be some hoops to go through to get that key, your secret document and some program to spit out whatever it is you are to send.

Then the fun really starts. You send your message, other party claims it could not be opened. So you go through the hoops again and re-send. At this stage you have probably changed a word or two in your source document. But that does not bother you because you are new to this. You send again. Another reply comes back - 'sorry mate...' - so you send again, probably introducing a few more edits.

Then you never hear back from them ever again. As it turns out you have been man-in-the-middled and those requests for a re-send were purely in the expectation that you would change your message slightly. This provides the 'crib' needed to open your message without knowing the key by our friends in Gloucestershire.

Where did my tin foil go?

I don't think that's as big an issue these days, given the rise of the smartphone - people just use their smartphone for email.

The solution is to make software so the smartphone can act as the smartcard if you really want to go that route.

Smartcard readers exist, and certain institutions use them already, the problem is getting the cards and readers to the masses.

The problem with the key exchange mechanism you've described is it's untrustworthy. The software would be essentially asking "is this initial email from the person you think it is?" which is a tough question to answer given the fact that emails can be readily spoofed. Granted, Bob's key will differ from Mallory's key, but there may be just enough time to do bad things before detection.

Key exchange between people should always require some kind of offline verification. If you don't do this, you can't really trust that the person you're communicating with is who they say they are. It's this key exchange process that's a pain in the ass and prohibits PGP's adoption. We've kinda solved this already with certificate authorities, but they're now considered a weak link in the chain.