We can generate truly random numbers by measuring random fluctuations known as noise We measure this noise through sampling to obtain numbers We can visualize this random sequence by drawing a path that changes direction according to each number known as a random walk **Random processes are non-deterministic **as they are impossible to determine in advance Machines are deterministic. Operation is predictable and repeatable Storing long random sequences can be memory intensive Mechanically Simulate the Scrambling Aspect of Randomness: 1. Select a truly random number, called the **seed** 2. Provide seed as input to a calculation Randomness of the sequence is dependent on the randomness of the initial seed only - Same seed and same sequence. #### Diff between Psuedo and Random - If you simulate them both via random walk, you will see that the psuedo random algorithm eventually repeats, when it reaches a seed it previously used - 2 digit seed --> 100 no. before reusing a seed and repeating the cycle - 3 digit seed --> can't expand beyond 1000 no. before repeating > Psuedo random number generates leave out many sequence that can not occur Psuedo random sequences sink down the key space for a truly random sequence What is possible vs what is possible in a reasonable amount of time --> practically secure vs perfectly secure