I am not too sure which kind I need to write. I am thinking it is an internal one because I am just trying to perform a proof-of-concept and I am not worried about having everything decoupled.
Maybe you can help me out with that... Basically what I want to do is have a plugin that is always listening for incoming requests on a certain name and is capable of interpreting an extended protocol, and then storing the data in a database. An example would be firstname.lastname@example.org listens. A server sends a custom stanza (something like server_specs) with a payload of data I am interested in. The email@example.com receives this and then is able to take the payload, parse it properly and store it for later use. Does that seem like an internal component?
It didn't even dawn upon me to look at the plugins that are already deployed. Thanks for the simple suggestion and I will post back if I run into any other major issues.