Question

To generate the sub-key P1 to P18 we use the hexadecimal equivalent digits of ____________

(a) 0.7864

(b) 0.1415

(c) 0.1542

(d) 0.7535

I had been asked this question in an interview.

This intriguing question comes from Blowfish Algorithm in section Pseudorandom Number Generation and Stream Ciphers and More Block Ciphers of Cryptograph & Network Security

Answer 1

Correct answer is (b) 0.1415

For explanation: To generate the sub-key P1 to P18 we use the hexadecimal equivalent digits of Pi-3 (only the decimal part).