Question: In Figure 31.10 in the text, why do we need an expansion P-box? Why cant we use a straight or a compression P-box? Figure 31.10

In Figure 31.10 in the text, why do we need an expansion P-box? Why can€™t we use a straight or a compression P-box?

Figure 31.10

In 32 bits Expansion P-box 48 bits XOR 4 - K; (48 bits) [48 bits f(R1. K; ) S-Boxes SSSSSSSS 32 bits Straight P-box 32 bits Out

In 32 bits Expansion P-box 48 bits XOR 4 - K; (48 bits) [48 bits f(R1. K; ) S-Boxes SSSSSSSS 32 bits Straight P-box 32 bits Out

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