question regarding cryptography

[wajahat]

Hello all,
i want to know is there any cryptography technique in which there is no prior information such as password ,keys etc to both the parties but still they are able to authenticate each other.

regards

wajahat

 

[M!k]

Take a look at public-key algorithms like RSA. Exchanging the public keys is still necessary, but - as it's public - there's no secure channel needed.
Authentication is done via challenge-response...

 

[123vincent]

try to device your algorithm in such a manner that the key is generated from the data bits itself. In this way, the key will change itself at every time making its decryption very difficult for an outsider.
in the decryption algo, the logic must be exactly opposite to that of encryption algorithm. In this way, the data bits will be sent over the unreliable channel without the physical delivery of keys to both the parties.
Hope it helps,
Regards,
Vincent