Q6. (10 pts) Given N=5, h(x) (2*x+2)mod 11. What will be the initial record for the user A in the Lamport's One-Time Password scheme? What password will be provided by A when the first time being authenticated by the server, S? What will be the new record of A in the S's database after the first successful A authentication? Give necessary explanations for your answers (select po = 2). Hint: Initialization Procedure The client selects a password, Po, a number, N, calculates PN = h (po). where hi+1(x)=h(h* (x)).h(x)= x The client securely delivers to the server (N.PN), and the server saves it into (Counter password.C_ID) tuple. Authentication Procedure When the client is requested for authentication by the server, S, the following proceeds: 1.C -->S:C_ID //elient sends his ID 2.S --> C: Counter{C_ID) //server responds by respective Counter value 3.C->S:C_ID, pwd Counter = h Counter - (po) 4. S: If h(pwd Counter) == password (C_ID) then S authenticates C, and sets (Counter password.C_ID- Counter - 1. pwd Counter.C_ID) Else is not authenticated Q6. (10 pts) Given N=5, h(x) (2*x+2)mod 11. What will be the initial record for the user A in the Lamport's One-Time Password scheme? What password will be provided by A when the first time being authenticated by the server, S? What will be the new record of A in the S's database after the first successful A authentication? Give necessary explanations for your answers (select po = 2). Hint: Initialization Procedure The client selects a password, Po, a number, N, calculates PN = h (po). where hi+1(x)=h(h* (x)).h(x)= x The client securely delivers to the server (N.PN), and the server saves it into (Counter password.C_ID) tuple. Authentication Procedure When the client is requested for authentication by the server, S, the following proceeds: 1.C -->S:C_ID //elient sends his ID 2.S --> C: Counter{C_ID) //server responds by respective Counter value 3.C->S:C_ID, pwd Counter = h Counter - (po) 4. S: If h(pwd Counter) == password (C_ID) then S authenticates C, and sets (Counter password.C_ID- Counter - 1. pwd Counter.C_ID) Else is not authenticated