cry and network system

1. Given the speed of a current ordinary computer (for home or light office use), estimate the amount of time necessary to crack a DES encryption by testing all possible keys. Make a similar estimate for a 128-bit AES key? Assume that a machine takes a hundred cycles per brute force against a single 56-bit DES key or 128 bit AES key and also that the household computer has a 2GHZ processor. 2. Draw one cycle of DES algorithm? 3. Construct a Playfair matrix with the key occurrence