Problem 1 (Authentication): Consider the following authentication protocol, which uses a classical cryptosystem. Alice generates a random message r, enciphers it with the key k she shares with Bob, and sends the enciphered message {r}k to Bob. Bob deciphers it, adds 1 to r, and sends {r + 1}k back to Alice. Alice deciphers the message and compares it with r. If the difference is 1, she knows that her correspondent shares the same key k and is therefore Bob. If not, she assumes that her correspondent does not share the key k and so is not Bob. Does this protocol authenticate Bob to Alice? If so, Why? Otherwise, explain why not.

Write a program that takes in 3 inputs [players (int type), expected game time (double type), team (char type)] and calculates actual game time (double) based on the following conditions: if the number of players or the expected game time is less than or equal to zero, it should output wrong input if the number of players is greater than 0 and less than or equal to 6 and if they are on the â€r’ or â€r’ team, their game time will be 10% faster. and if they are on the â€b’ or â€b’ team, their game time will be 15% faster. and if they are on the â€y’ or â€y’ team, their game time will be 20% faster. and if they are on any other team, they will play 0% faster. if the number of players is greater than 6 but less than or equal to 12 and if they are on the â€r’ or â€r’ team, their game time will be 20% faster. and if they are on the â€b’ or â€b’ team, their game time will be 25% faster. and if they are on the â€y’ or â€y’ team their game time will be 30% faster. and if they are on any other team, they will play 0% faster. if the number of players is greater than 12 but less than or equal to 18 and if they are on the â€r’ or â€r’ team, their game time will be 30% faster. and if they are on the â€b’ or â€b’ team, their game time will be 35% faster. and if they are on the â€y’ or â€y’ team, their game time will

Which type of tab stop is most for weights and measurements?

You need to design a circuit that implements the functions in the following table: s0 s1 function0 0 a + 10 1 a – b1 0 a + b1 1 a – 1s0 and s1 are 1-bit control inputs to select the function of the circuit. inputs a and b are 4-bitnumbers in 2s complement form. the output is also a 4-bit number in 2s complement form.you are allowed to use only one ttl 7483 4-bit adder to implement all the functions. but anynumber of other components (except the adder) can be used.hint: design a combinational logic circuit to modify the input b and the “carry input” of theadder depending on the control inputs s0 and s1.important: lab grade will depend on the working of the circuit & will be checked of by your labinstructor.1. is the output valid for the following input combinations: a. s0 = 0, s1 = 0, a = 7, b = 3? b. s0 = 0, s1 = 1, a = 7, b = 3? c. s0 = 1, s1 = 0, a = -4, b = -5? d. s0 = 1, s1 = 1, a = -8, b = 6? 2. what is the range of inputs (for both a and b) that will produce the valid output for all the functions?