5 ms·

I think the issue there is it would be an anonymous chat room - how would you know who sent the message?

• javajosh 7y ago
  Glad you asked. My solution allows for anonymous rooms, but "solution 2" does not. To be anonymous, just post ordinary text to the room using K. To be identified, post your text, your signature all encrypted with K.
  • thinkloop 7y ago
    Yes that's right. Normally for signatures you would do the final encryption with the receiver's public key creating the same issue as solution #1, but in this case you would use the symmetric key: 1. Hash message 2. Encrypt hash using your private key 3. Encrypt again using group's symmetric key There's obviously good reason why symmetric keys don't work, especially in place of solution #2 - would be great to be enlightened on why by the author.