I've created the following KIP and I'd appreciate any comment on the proposal:
https://cwiki.apache.org/confluence/display/KAFKA/KIP-38%3A+ZooKeeper+Authentication <https://cwiki.apache.org/confluence/display/KAFKA/KIP-38:+ZooKeeper+Authentication> This is in progress and there is code for most of it already. Please check the corresponding PR if you're interested. Thanks, -Flavio