There is no "IP camera protocol"
An IP camera really just means a camera that is accessible by web pages,
usually with different pages for still or streaming output (mjpeg).
There are several ways you could do that on a Pi
"motion" is an all-in-one package with its own webserver, motion detection and command rules etc all built in,
but you could roll your own with apache, mjpg-streamer etc
As well as a usb camera, you can of course use the new raspberry camera...
Android app - Raspi Card Imager - download and image SD cards - No PC required !