subject
Computers and Technology, 20.02.2020 19:19 gmc2771

You and your friend who lives far away want to fairly and randomly select which of the two of you will travel to the other’s home for a visit. Your friend remembers having learned about using hashes as cryptographic commitments and proposes to use a coin toss to decide. He tells you to randomly choose ‘heads’ or ‘tails’ by throwing a coin, hash the result using sha256, and send him the hash. Once you have committed to the outcome, he’ll guess ‘heads’ or ‘tails’, you’ll reveal to him your choice and he can verify that the hash is correct. If his choice matches your coin toss, then your friend wins and you have to make the trip. What is the problem with this scheme, as described?

a. there’s no way to prove that your coin toss is random
b. there’s no way to prove that sha256 is collision resistant
c. your friend can hash all possible options and discover your secret
d. unless you sign the hash message your friend can’t be sure it was you who sent it

ansver
Answers: 2

Another question on Computers and Technology

question
Computers and Technology, 22.06.2019 23:50
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?
Answers: 3
question
Computers and Technology, 23.06.2019 02:30
What is the power dissipated by a resistor with a current of 0.02 a and a resistance of 1,000 ? a. 200 w b. 20 w c. 0.4 w d. 4 w
Answers: 1
question
Computers and Technology, 23.06.2019 18:40
Johnson enterprises uses a computer to handle its sales invoices. lately, business has been so good that it takes an extra 3 hours per night, plus every third saturday, to keep up with the volume of sales invoices. management is considering updating its computer with a faster model that would eliminate all of the overtime processing.
Answers: 2
question
Computers and Technology, 24.06.2019 16:00
5.a fishing rod is formed from a composite material of 0.5 kg of glass fibers embedded in a matrix of 0.5 kg of epoxy resin. the glass fibers are assumed to be long, continuous and unidirectional. to achieve a greater stiffness it is proposed to use a different composite that is comprised of long continuous carbon fibers that will be embedded in a matrix of 0.5 kg of epoxy resin. if the modulus of elasticity of the carbon fiber composite is 10% greater than the elastic modulus of the glass fiber composite, estimate the mass of carbon fibers that will be used to make the carbon fiber composite. assume the applied tensile stress is parallel to the direction of the long axis of the fibers. the epoxy resin, glass fiber, and carbon fiber have an elastic modulus of 5, 86, and 350 gpa respectively and a density of 1100, 2500, and 1800 respectively.
Answers: 3
You know the right answer?
You and your friend who lives far away want to fairly and randomly select which of the two of you wi...
Questions
question
Mathematics, 29.10.2020 01:00
question
Arts, 29.10.2020 01:00
question
Mathematics, 29.10.2020 01:00
question
Mathematics, 29.10.2020 01:00
question
Mathematics, 29.10.2020 01:00
Questions on the website: 13722367