Security Reinforcement

Multiple encryption

Breakable with a meet-in-the-meddle attack in $2^{n+1}$ attempts.

Not secure enough (theoretically).

Usually K1 = K3.

If K1 = K2 = K3, then we get simple encryption

A simple and efficient technique to add confusion.

Last updated 1 year ago

Multiple encryption

Double encryption

Breakable with a meet-in-the-meddle attack in

2^{n+1}

attempts.

With 2 or more known plaintext blocks.

Using 2^n blocks stored in memory.

Not secure enough (theoretically).

Triple Encryption (EDE)

Ci = Ek3 * (Dk2 * (Ek1 * Ti))

Pi = Dk1 * (Ek2 * (Dk3 * Ci))

Usually K1 = K3.

If K1 = K2 = K3, then we get simple encryption