### Re: [Cryptography] prism-proof email in the degenerate case

* John Denker j...@av8n.com [2013-10-10 17:13 -0700]: *) Each server should publish a public key for /dev/null so that users can send cover traffic upstream to the server, without worrying that it might waste downstream bandwidth. This is crucial for deniabililty: If the rubber-hose guy

### Re: [Cryptography] prism-proof email in the degenerate case

-BEGIN PGP SIGNED MESSAGE- Hash: SHA1 On 10/10/2013 6:40 PM, grarpamp wrote: On Thu, Oct 10, 2013 at 11:58 AM, R. Hirschfeld r...@unipay.nl wrote: To send a prism-proof email, encrypt it for your recipient and send it to irrefrangi...@mail.unipay.nl. Don't include any information

### Re: [Cryptography] prism-proof email in the degenerate case

On Thu, Oct 10, 2013 at 03:54:26PM -0400, John Kelsey wrote: Having a public bulletin board of posted emails, plus a protocol for anonymously finding the ones your key can decrypt, seems like a pretty decent architecture for prism-proof email. The tricky bit of crypto is in making access to

### Re: [Cryptography] prism-proof email in the degenerate case

grarpamp wrote: On Thu, Oct 10, 2013 at 11:58 AM, R. Hirschfeld r...@unipay.nl wrote: To send a prism-proof email, encrypt it for your recipient and send it to irrefrangi...@mail.unipay.nl. Don't include any information about To receive prism-proof email, subscribe to the irrefrangible

### Re: [Cryptography] prism-proof email in the degenerate case

On Thu, Oct 10, 2013 at 04:22:50PM -0400, Jerry Leichter wrote: On Oct 10, 2013, at 11:58 AM, R. Hirschfeld r...@unipay.nl wrote: Very silly but trivial to implement so I went ahead and did so: To send a prism-proof email, encrypt it for your recipient and send it to

### Re: [Cryptography] prism-proof email in the degenerate case

On 10/10/2013 08:54 PM, John Kelsey wrote: Having a public bulletin board of posted emails, plus a protocol for anonymously finding the ones your key can decrypt, seems like a pretty decent architecture for prism-proof email. The tricky bit of crypto is in making access to the bulletin

### Re: [Cryptography] prism-proof email in the degenerate case

Hi, sm...@immi.is commented: #An alternative I've been considering is having e-mail clients support #bouncing messages if they are received for an incorrect envelope #address. So you can have an envelope address and a PGP encrypted blob, #and when you decrypt that blob there's a new RFC822

### [Cryptography] prism-proof email in the degenerate case

Very silly but trivial to implement so I went ahead and did so: To send a prism-proof email, encrypt it for your recipient and send it to irrefrangi...@mail.unipay.nl. Don't include any information about the recipient, just send the ciphertext (in some form of ascii armor). Be sure to include

### Re: [Cryptography] prism-proof email in the degenerate case

Having a public bulletin board of posted emails, plus a protocol for anonymously finding the ones your key can decrypt, seems like a pretty decent architecture for prism-proof email. The tricky bit of crypto is in making access to the bulletin board both efficient and private. --John

### Re: [Cryptography] prism-proof email in the degenerate case

The simple(-minded) idea is that everybody receives everybody's email, but can only read their own. Since everybody gets everything, the metadata is uninteresting and traffic analysis is largely fruitless. Some traffic analysis is still possible based on just message originator. If I see

### Re: [Cryptography] prism-proof email in the degenerate case

On Oct 10, 2013, at 11:58 AM, R. Hirschfeld r...@unipay.nl wrote: Very silly but trivial to implement so I went ahead and did so: To send a prism-proof email, encrypt it for your recipient and send it to irrefrangi...@mail.unipay.nl Nice! I like it. A couple of comments: 1. Obviously,

### Re: [Cryptography] prism-proof email in the degenerate case

-BEGIN PGP SIGNED MESSAGE- Hash: SHA1 Cool. Drop me a note if you want hosting (gratis) for this. On 10/10/13 10:22 PM, Jerry Leichter wrote: On Oct 10, 2013, at 11:58 AM, R. Hirschfeld r...@unipay.nl wrote: Very silly but trivial to implement so I went ahead and did so: To send

### Re: [Cryptography] prism-proof email in the degenerate case

Having a public bulletin board of posted emails, plus a protocol for anonymously finding the ones your key can decrypt, seems like a pretty decent architecture for prism-proof email. The tricky bit of crypto is in making access to the bulletin board both efficient and private. This idea has

### Re: [Cryptography] prism-proof email in the degenerate case

On 10/10/2013 12:54 PM, John Kelsey wrote: Having a public bulletin board of posted emails, plus a protocol for anonymously finding the ones your key can decrypt, seems like a pretty decent architecture for prism-proof email. The tricky bit of crypto is in making access to the bulletin

### Re: [Cryptography] prism-proof email in the degenerate case

On Oct 10, 2013, at 5:20 PM, Ray Dillinger b...@sonic.net wrote: On 10/10/2013 12:54 PM, John Kelsey wrote: Having a public bulletin board of posted emails, plus a protocol for anonymously finding the ones your key can decrypt, seems like a pretty decent architecture for prism-proof email.

### Re: [Cryptography] prism-proof email in the degenerate case

On 10/10/2013 02:20 PM, Ray Dillinger wrote: split the message stream into channels when it gets to be more than, say, 2GB per day. That's fine, in the case where the traffic is heavy. We should also discuss the opposite case: *) If the traffic is light, the servers should generate cover

### Re: [Cryptography] prism-proof email in the degenerate case

On Thu, Oct 10, 2013 at 11:58 AM, R. Hirschfeld r...@unipay.nl wrote: To send a prism-proof email, encrypt it for your recipient and send it to irrefrangi...@mail.unipay.nl. Don't include any information about To receive prism-proof email, subscribe to the irrefrangible mailing list at

### Re: [Cryptography] prism-proof email in the degenerate case

On Thu, 2013-10-10 at 14:20 -0700, Ray Dillinger wrote: Wrong on both counts, I think. If you make access private, you generate metadata because nobody can get at mail other than their own. If you make access efficient, you generate metadata because you're avoiding the wasted bandwidth that