most ip cameras work with the same protocol.
there are a couple of forums that discuss the capabilities and APIs of those cameras.
its pretty straight forward of you want to display a jpg. its getting more complicated for mpg or streaming a series of pictures to create a pseudo video feeling.
I am using this technology to preview the channels on the remote without having to switch on the projector etc....
One nice place to start is the "...9100 yahoo forum Dedicated to the reverse-engineering of AVIOSYS 9100A and 9100A Plus IP VIDEO server, and other similar devices based on W90N740, and ARM7TDMI chip by Winbond". This is a widelly used chipset for ipcameras and AV Servers.
try those links as a starting point
[Link: tech.groups.yahoo.com][Link: aviosys.com]hope it helps. good luck
Dimitris