encryption and spying servers

hmm was just thinking sorta along the lines of encryting msgs and sending them to another person via a server. Now say the server is wanting so read you msg. Was thinking of ways of stoping this from happening. Now before you say encrypt it with an algorithim that the 2 parties both know I want it to be that neither have ever spoken to each other before.

For the arguments sake lets call the poster- A and the server-B
the receiver can be C, any1 care to take a shot? I have been thinking about this a little and I am at an end.

Encrypt it, but send the key in a separate message AFTER you send the message. Preferably through a different server (ie an instant messenger or different email address). Just an idea. Hope this helps

look up public key encryption that will help you out

yeah Public key encryption is ok but I am not so sure about it I mean there are people who collect numbers like that as a hobby I am sure some1 is bound to get it. And I know there are many ways of getting round it while using other servers and so forth but I am talking JUST sender-A server-B and receiver-C

It is looking imposible but nothing is imposible (or so they say) so...

Well, that depends on how critical the information is you're sending. Ever considered FedEx? If not, pgp is quite a standard right now for public key encryption, you could also take a look into ibe here http://crypto.stanford.edu/ibe/, looks like a nice alternative to pgp. Even if someone was intended on reading your messages, they would have to go through a lot of work to do this. Again, REALLy confidential information shouldn't be sent via e-mail imho,

It depends,

How smart is the sysadmin for the server,
and how smart is the reciever?

Because if the reciever is smarter then the admin,
then you could use very simple encryption,
under the assumption that the reciever would know
how to break it, and the sys-admin couldnt.

By simple encryption, I mean whatever the reciever would
be able to understand, but the sysadmin wouldnt.

It could be somthing like rotary encryption 13,
or even somthing as simple as your signature there.

By the way, I like the signature.


-8trak

That's assuming that this is just theoretical right??

Because what i was saying would be a serious pain in the ass in real life.


-8trak

If you use a public-key/private-key algorithm, the main problem is getting your public key to the other person (and vice versa) without someone tampering with the information and making a man-in-the-middle attack. To solve that, simply send one of the public passwords to the other person one way, and get the other through a different route.

A spying server could not execute a man-in-the-middle without tricking BOTH people into using the wrong keys...

I would just call them up, give them the password, and use something like Scramdisk or an encrypted .zip file with a <8 character password.

hmm this string is all hypothetical if I was going to send a message I wouldn't be using a server that is gonna be spying on me in the first place. I had a thought that say

if sender -A encrypts the msg and puts it on server - B
then receiver - C encrypts it with his/hers own encryption and puts it back on B.

Then A unencripts the new msg to leav the msg encrypted in C's encryption.

The problem with this is that B will be able to A's first encryption by comparing the encrypted msg's.