"Todd Pattist" wrote:
Tim Newport-Peace ] wrote:
It was suggested:

A: All Purposes including World Records.
B: Badges and Diplomas
D: Badges up to Diamond

What is the rationale for distinguishing between levels B
and D? If I understand correctly, D was initially separated
from everything else because of concerns about cheating,
then B was shown to be hackable (Wedekind). If that's
correct, why wasn't B moved into group D? Or, more
preferably, why isn't D given the same privileges as B?

The Diamond-level approval exists to allow for equipment with minimal
physical security. The only flight recorders in that category, at present,
are the EW models which connect to external GPS units.

Instead of ratcheting up costs, why can't we just use our
Official Observers to control cheating? We relied on them
for decades before RSA/DSA and public/private key
encryption.

Costs are ratcheting up only in the sense that some flight recorders that
could formerly be used for world records no longer can be. If the private
keys in the flight recorder are compromised, we can't depend upon Official
Observers to prevent cheating. There are a number of ways to cheat which
will not be visible to even the most diligent observer using present
procedures. The observer procedures could be altered to require more
intrusive inspection and monitoring of the flight (much like the
camera/barograph/chronometer days), but I think it a better compromise to
accept the fact that some older flight recorder designs just don't provide
the level of security assurance desirable for world records.

If I hack an A level recorder (with a GPS
transmitter simulator and a pressure chamber or by opening
the case and inserting GPS code between the off-the-shelf
GPS receiver and the custom circuitry), can we just agree
that no security is perfect and group them all as imperfect,
but usable for all levels with appropriate monitoring by an
OO?


Of course the security of even "A" level flight recorders is imperfect.
There are no perfect security systems. We are just trying to find an
appropriate balance between the security requirements, and convenience for
pilots and observers. It's not quite as simple to find that balance as you
might think...

Marc