Messaging patterns in ZeroMQ

As outlined here http://www.aosabook.org/en/zeromq.html, one can look upon all messaging to fall in these categories

1. Publish/Subscribe
2. Synchronous Request/Reply
3. Asynchronous Request/Reply
4. Push/Pull
5. Parallelised pipeline 

Refer to https://blog.scottlogic.com/2015/03/20/ZeroMQ-Quick-Intro.html for how this is used . The idea is to have "smart endpoint, dumb network", unlike Kafka which is a "dumb endpoint, smart network" model. The clients essentially connect to the server, and the server communicates to the clients based on the above messaging modes. Note that the clients and server can both be on the same machine (IPC) or even different threads in a process talking via an "endpoint" etc.