If you are looking for the code moodle uses then you can find it on github. Moodle is written in php if thats what you mean by protocol.
Thanks for reply.
No. I meant there are several options available in moodle, like CAS, LDAP, IMAP etc.
Also, I tried to go via https://docs.moodle.org/dev/Creating_a_web_service_client
But, couldn't find any idea where can I go and start working on for the JWT token method.
One of my other web application has created JWT token and given me the key. I need to sign in the user into Moodle.
Can not understand where to start with? At which place I can get the code.
I'm not aware of any published authentication plugins that implement JWT - searching in the plugins DB for JWT doesn't show any results ( https://moodle.org/plugins/?q=jwt ).
It is certainly possible to create an authentication plugin that works with JWT, as I've seen it done, but you're probably going to need to write code (or find someone to write code) to do it - https://docs.moodle.org/dev/Authentication_plugins might be a starting point (or looking at any of the examples in the standard auth/ directory).