You're focussing too much on a specific type of encryption and forgetting one important thing I think.
The problem is the _implementation_ of the encryption, whatever kind of encryption that is or however it uses public, private or whatever keys, doesn't matter:
quote:
Originally posted by Shiroi
Yes right MP!L is not an IM-Client but I thought it may operate on the layer between Windows Live Messenger and the port it communicates through. If that's not the case, yes it might be very troublesome to implement encryption.
Even if it operates in that layer, the same restrictions still apply though: not everybody uses Plus!, and most importantly:
there is no way to know who uses it and who doesn't.
(you don't want to have people recieving gibberish and not knowing what todo with it).
quote:
But if it's operating on this layer it should be possible to allow encryption without knowing if the the other person supports this encryption or not. Because on the very begin of conversation OTR must share the temporary keys between the conversation partner (in a safe way that there is no man in the middle) that he will be able to decrypt your message. If this fails (because you get no answer from the other client on this request) you know that he can't decrypt your message.
That is purely based on the fact that you send out hidden information first.
That is exactly what Plus! will not do because of privacy reasons. And that is the entire point why an encryption function (again, no matter what encryption) wont work.
quote:
Actually there is already software available called otrproxy which allows to encrypt Microsoft Live Messenger messages but it seems like they stopped developing on it.
Just like everything else, both parties must use it in order for it to work. And you can't know if the other party uses the exact same thing as you.
Bottom line: a proper encryption system is never going to work/be popular when implemented with addons or other 3rd party IM clients using the MSN Network.
If proper encryption is needed for the MSN Network, then it must be done on protocol/server level within the main client (Windows Live Messenger) itself.
In that way you can make sure that whatever you encrypt (or not), the other party can read it. Any other method using 3rd party stuff has severe limitations and thus will never be successfull since what is the point of using encryption if your contact can't read it.
As such, I think you should instead request encryption to the Windows Live Messenger team itself (http://support.live.com or via the main menu: Help > Send feedback).
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