beret7a said:
Thanks for both comments, are you aware of existing documentation for FPS ?
I'm not completely sure what sort of documentation you're referring to, but there are often resources to be found online, examining various in-game actions, inspecting packets sent or trying to explain the netcode.
An early type of netcode used for our FPS back in the DOS days is lockstep, which is described here.
Quake 3 has a well-known and more sophisticated netcode, described here.
Now the exploits might not relate directly to netcode; Counter-strike wallhack IIRC was just forcing a different set of vertex attributes to the graphics card - please correct me if I'm wrong. You could also deem rocket-jumping an exploit, and once you could move sqrt(2.0) instead of 1.0 per tick, by moving forward/backwards at the same time as sideways. I'm not sure what that was called, but in official documentation or source code, you'd have to really drill into it to uncover stuff like that.
But there is potentially a lot of ground to cover. Finding good resources that have already reverse-engineered the games you want to cover might be a good idea. I doubt you'd appreciate reading official documentation or source to get information on exploits, network-related or otherwise.