Again, referring to Alice from the Textbook, Instead of an online bank, suppose that Alice provides an online chess playing service known as Alice's Online Chess $($AOC$).$ Players, who pay a monthly fee, log into AOC where they are matched with another player of comparable ability.

a$.$ Where should cryptography be used in AOC?

b$.$ Where should access control used?

c$.$ Where would security protocols be used?

d$.$ Is software security a concern for AOC? Why or why not?

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