Re: How can airlines stop hackers pwning planes over the air?
This.
Airgaps. Airgaps. Airgaps! I assume the reason there is a connection between the avionics and in flight entertainment so they can put up those nice little maps showing where you are, current airspeed, etc. There probably isn't even a firewall, because the interface was designed back when they couldn't foresee everyone bringing a personal device with them that has the computing power of a high end mid 90s server that would be permitted wireless access to the in flight entertainment network.
The story is the same as automotive entertainment and CAN bus, if you want to get data out of the important systems responsible for stuff that matter like flaps, brakes and what not, you can't use TCP/IP. Use a serial connection, with one direction clipped, so it is one way data only. Then you can get the data to make the pretty displays about where your flight is, or access engine data like rpms, without worrying about leaving security holes that let a passenger crash the plane.
At least planes can't be hacked from the ground (well maybe they can, but not without some insider info, and there are a few people out there who would love to crash the plane they are riding on) and so long as cars could only be hacked from the inside it wasn't an issue. After all, if you want to crash a car, the steering wheel is an easier method than the ODB-II connector. But now that more and more cars can be accessed remotely, this is a real concern. Someone is going to die from this someday...or maybe already has and the crash investigators didn't realize it because they didn't know where to look!