Consider Needham-Schroeder key exchange protocol, which is presented below: Step 1: Alice  Cathy: {Alice || Bob || rand1} kAlice Step 2: Cathy  Alice: {Alice || Bob || rand1 || ksession || {Alice || ksession} kBob} kAlice Step 3: Alice  Bob: {Alice || ksession} kBob Step 4: Bob  Alice: {rand2} ksession Step 5: Alice  Bob: {rand2 – 1} ksession 1. Discuss each of the five steps of Needham-Schroeder protocol in detail. 2. Show how Alice is convinced that she is talking to Bob. 3. Show how Bob is convinced that he is talking to Alice.

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?

The managing director of a company sends a christmas greeting to all his employees through the company email. which type of network does he use? he uses an .

Based on the current economic situation do you expect the employment demand for graduating engineers to increase or decrease? explain the basis for your answer. with a significant economic recovery, what do you think will happen to future enrollments in graduating engineering programs?