Today, I got a question about SMUX. After answering the question, I decided to blog about it so you all can also become familiar with SMUX.
What is SMUX?
In short, SMUX is a session management protocol. SMUX separates the underlying transport from the upper level application protocols. According to W3C, SMUX aims to
ease transitions to future Web protocols, and communications of client applets using private protocols with servers over the same TCP connpcection as the HTTP conversation
For more information about SMUX, read the SMUX protocol specification at W3.org
You can see whether SMUX is on your server running by invoking
nmap -p 1-65535 localhost
199/tcp open smux