For privacy, GSM can use the A5/1 stream cipher. Write (your own) implementation of A5/1 in python (and include with your answers). Answer the following questions

(e) Assume that the 64-bit session key is Kc = 0x9876543210abcdef. Assume that the 22-bit frame number Fn = 1. What are the first 64-bits of keystream output from A5/1?

(f) How many 114-bit A5/1 keystreams can you generate per second? To answer this question, include your python code for computing this rate.

(g) Given 114-bits of keystream from A5/1, how long would it take to recover the A5/1 key Kc used to generate the keystream with your A5/1 implementation?