We’ve had a couple conversations about random peer sampling problems, both around improving mix network PKIs, as well as directly for usage in libp2p. I’ll start a thread for discussing the literature:
Brahms provides a basic system for actively gossiping nodes, while restricting access to the node list from which you sample.
Julius Bunger implemented and improved Brahms for GNUNet, which sounds quite promising, but the improvements seem under documented so far.
There is an interesting measure of randomness in sampling proposed in Uniform Node Sampling Service Robust against Collusions of Malicious Nodes by Emmanuelle Anceaume, Yann Busnel, and Bruno Sericola.