I'm looking to implement a performant revocation method for JWTs. I'm reading a paper, in which the following section's second paragraph states:
If we use the client hashing approach described previously, we have a greater volume of keys to deal with. One possible approach would be to generate the secret using a set synchronized cryptographically secure pseudorandom number generators, creating a kind of rolling code for each group of clients. This would mean that only the key change events have to propagate, not the actual keys themselves, greatly reducing the associated performance cost.
What is a set synchronised cryptographically secure pseudorandom number generator (CSPRNG)?
I know what a CSPRNG is, in that it is a random number generator with an acceptable degree of randomness. But what is the set synchronised part? Does it relate to synchronised sets in Java? What does being set synchronous achieve in this context?