Which is a characteristic of IDEA?

A.
56 bytes

B.
64 bits

C.
64 bytes

D.
All of the above
E. None of the above

Explanation:
From Wikipedia: International Data Encryption Algorithm (IDEA) operates on 64-bit
blocks using a 128-bit key, and consists of a series of eight identical transformations (a round, see
the illustration) and an output transformation (the half-round). The processes for encryption and
decryption are similar. IDEA derives much of its security by interleaving operations from different

groups — modular addition and multiplication, and bitwise eXclusive OR (XOR) — which are
algebraically “incompatible” in some sense.