If you want to dig deep into these topics I recommend checking out the reference info in these repositories:
- About pubsub: https://github.com/libp2p/research-pubsub/
- includes a call for lit review materials that recommends reading this article for a “very comprehensive overview”: http://dl.acm.org/citation.cfm?id=2543583
- About CRDTs: https://github.com/ipfs/research-CRDT