I am implementing a cryptographic protocol and I'd like to generate a set of seeds using a seed for a pseudo-random function. The reason is that I can pass on only one seed and it can be used to generate the other seeds.
As we know each derived seed is used to generate a set of pseudo-random values.
According to pseudo-random function definition, the seeds must be truly random (and not pseudorandom). So if I use a master seed to generate some other seeds the derived seed would not be truly random (according to the definition).
Question 1: How can I fill the above gap (i.e. satisfy the pseudorandom function) and have a secure key derivation function?
Question 2: Are the key derivation functions deterministic (i.e. given a master key it always generates a set of derived keys)?