hi, An extract frm this months cryptogram goes as below. ----------------------------------------------------
On the other hand, if you ever find a product that actually uses a one-time pad, it is almost certainly unusable and/or insecure. So, let me summarize. One-time pads are useless for all but very specialized applications, primarily historical and non-computer. And almost any system that uses a one-time pad is insecure. It will claim to use a one-time pad, but actually use a two-time pad (oops). Or it will claims to use a one-time pad, but actually use a steam cipher. Or it will use a one-time pad, but won't deal with message re-snchronization and re-transmission attacks. Or it will ignore message authentication, and be susceptible to bit-flipping attacks and the like. Or it will fall prey to keystream reuse attacks. Etc., etc., etc. ----------------------------------------------------- Though it has a large key length greater than or equal to the plain text,why would it be insecure if we can use a good pseudo random number generators,store the bits produced on a taper proof medium. how about this way P=Plain text C=Cipher text R=Pseudo random bits(the pad) To transmit a secret frm point A to Point B Choose ur agent-Send cipher text(C) to B. If( Cipher text C is intercepted,do not send R.) without R, C cannot be decrypted Else(If C is securely transmitted to point B,choose an agent and send R to point B) If R is intercepted the secret remains safe,since they donot have C. If initially C was intercepted ,R is not send,another pad is chosen. It is assumed that the agent is trust worthy.Also the agent has to send receipt for the safe arrival of C at point B before R is transmitted. It is also assumed that cryptographical secure pseudo random numbers are use. Cryptography does not address the problem of dishonest users-does it? The difficulty for attaining highest security is more. why do we always have to rely on the internet for sending the pad?If it is physically carried to the receiver we can say for sure if P or R is intercepted. can some one answer the issues involved that one time pads is not a good choice. Thank you Regards Sarath. __________________________________________________ Do you Yahoo!? Faith Hill - Exclusive Performances, Videos & More http://faith.yahoo.com
