I would like to add a ticket based authentication mechanism to my network. Can you give me brief idea where do I start, which language should i write the protocol in and how do i get those in my custom openwrt firmware.
You might be interested in this.
https://openwrt.org/docs/guide-user/services/remote_control/ostiary.server
You can do all kinds of things with it, as is, or build on the idea and do your own thing with it.