We've all heard about the infamous CAP theorem, and how it's impossible to "beat".  But what does that really mean?  Should we throw down our keyboards and give up on running a distributed system?

This talk will discuss consensus protocols, the actual definitions of every letter in that acronym, and what real issues come up when it comes to running a performant, correct, distributed system.  If you've ever wondered why Paxos has to be so complicated or what "partition tolerance" really means this talk is for you.