End to End Group Communication

Mesh/Recrypt is described in detail in draft-hallambaker-mesh-recrypt

Mesh/Recrypt is a protocol that uses recryption to enable end-to-end communications between groups of users. This page sets out the reason recryption is interesting and useful. For more information see these resources:

1 Key

Is good

2 Keys

Is better

3 Keys

Is ?

Public key cryptography is much more powerful than the systems that preceded it because it uses separate keys for encryption and decryption. Unlike traditional one key (symmetric) cryptography in which the same key is used to encrypt and decrypt, public key cryptography uses two separate keys for two separate functions. And that means that we can give anyone the ability to encrypt a message without giving them the ability to decrypt.

Since two key cryptography has been so much more successful and useful than one key. What could we do if we used even more keys? It turns out that we can do a lot more with a three key cryptographic system known as proxy re-encryption, recryption for short.

Group Communications

Applying recryption technology, a group of users has a single encryption key but each group member has a separate decryption key. An online recryption service converts messages encrypted under the group key so that it can be decrypted by an individual subscriber but cannot decrypt the messages itself.

Recryption technology allows end-to-end security to be achieved in any cloud application where the cloud is required to store or transmit data but not perform calculations on the data itself

Untrusted Cloud

Device Specific Encryption

Recryption can't save the data that has already been disclosed but it does allow the hole to be closed before more data leaks.

Mesh/Recrypt is an experimental messaging protocol being developed using the Mesh as the foundation. Mesh/Recrypt extends the functionality of existing messaging systems by adding the following novel features:

  • Supports synchronous (chat, voice, video) and asynchronous messaging (mail, file store, mailing lists, comment forums) in a single client. Users may switch between modes of communication seamlessly.