(Choose 1 answer)
FU inish the exam.
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Which of the following describes the 2nd block encryption output of CBC mode (C2). The followings are given:
E (an encryption cipher function), K (the key). C1 (the cipher output from the 1st block encryption), P2 (the
plaintext for the 2nd block), and XOR (and exclusive-or function). For example, XOR(x,y) indicate the bit-by-bit
XOR between the two bit vectors x and y, and E(K,P2) is the encryption output when using the key K and the
plaintext P2
A. C2 XOR(P2,E(K,XOR(C1,P2)))
B. C2= XOR(P2,E(K,XOR(C1,P1)))
C. C2 XOR(P1,E(KXOR(C1,P1)))
D. C2 E(K,XOR(C1,P1))
E. C2 XOR(E(C1),K)
F. C2 E(KXOR(C1,P2))
Ext
