At 10:31 AM 10/11/2000, Ray Dillinger wrote: ...
Also, it looks like the sort of thing that could be designed around. If someone were building a "secure laptop" they could make a video system and drivers that wrote the bits in a different, randomized order each time, and which only wrote the changed bits. If anybody is actually making a product like this, it would be a strong indication that *somebody* with money to spend on R&D considers it a valid threat model, because nobody makes products without a market.
This could easily be the recipe for a flickering monitor. First of all, the refresh rate needs to be probably in excess of twice what the human eye can see, just so a random signal can be detected before the old signal has expired. if you can count to 4 in n length of time, then you can only reliably provide all the information in that time by keeping to the same order. 1,2,3,4. or 4,3,2,1 or 1,3,2,4, etc. But not 1,2,3,4,3,2,4,1. By the time it rewrote 1, the old 1 would be out of date, and it would appear that you had video problems, (shortly followed by a headache). If you can count to 16, but only need to count to 4, then your options are tremendous. 1,2,3,4,3,4,2,4,2,3,1,2,4, 11 commands from 1 to the next 1 in this example. from line to that same line. This would allow for a secure monitor that didn't invite eyestrain. Good luck, Sean