OLC and Cambridge 10/20/25 support ending

On Dec 11, 11:11*pm, Max Kellermann wrote:
You're right by saying it's an illusion, but I strongly disagree that
a server-side service is a viable solution.

What if you don't have internet access?

What if the server is down?

What if the server is commercial (like the OLC), and I object to use
that?

Please note that this thread is entitled "OLC and Cambridge 10/20/25
support ending", and that it is quite hard to use the OLC without at
least occasional access to the internet, and some amount of
willingness to put up with OLC policies.

This problem is not something that should put Cambridge owners in a
dependency situation on one entity. *This problem can be solved with a
free tool that does not require internet connection, and that does not
require this kind of dependency. *If such a solution is possible, it
should be done that way.

The owners of every approved flight recorder, so far, are each
dependent on the manufacturer of their flight recorder, nothing is
different here. Validation source code has never been publicly
released for any approved flight recorder, although that might well
change some day. In any case, usable validation source code for the
GPS-NAV can never be released, as it does not use public key
cryptography.

If this can technically only be achieved by storing the whole verbatim
Cambridge file (including the verbatim signature; using base64?) in
the IGC file, then be it so. *It's not 1995 anymore, and inflating the
IGC files is the lesser evil.

That can be done, and then what? At the other end, you'd need to
extract the embedded CAI file, and run VALI-CAM.exe followed by CONV-
CAM.exe to be certain of getting the valid IGC file. It would be
simpler to submit the original CAI file in the first place...

Marc

Marc wrote:
The owners of every approved flight recorder, so far, are each
dependent on the manufacturer of their flight recorder, nothing is
different here.

The difference is that Cambridge cannot revoke my rights to use my
logger, but an online service can do that at any time. I have to
permanently agree to the server's terms of service to use it, while I
don't have to agree to anything to use my logger. This is a huge
difference. Maybe not for you, but I care a lot about such things
that may potentially limit my freedom.

Validation source code has never been publicly released for any
approved flight recorder, although that might well change some day.
In any case, usable validation source code for the GPS-NAV can never
be released, as it does not use public key cryptography.

Which means that a key that can generate "valid" CAM files is already
disclosed to the public. How will your proposed server-side solution
address that problem? How will your server identify tampered CAM
files?

That can be done, and then what? At the other end, you'd need to
extract the embedded CAI file, and run VALI-CAM.exe followed by CONV-
CAM.exe to be certain of getting the valid IGC file.

I was looking forward to a solution that may include a free VALI-CAM
program which could be embedded in my own software, but sadly that is
a pipe dream. I hope this dream comes true one day for a logger. For
this to come true, pilots should express this wish, which I hereby do
(or, better, I try to convince other pilots of the advantages of free
validation procedures).

It would be simpler to submit the original CAI file in the first
place...

The CAI-inside-IGC approach has the advantage that any software may
evaluate the flight without having to implement another (proprietary)
file format. But yes, uploading the verbatim CAI binary file instead
of IGC is another interesting approach that could be considered.
Again, that would require that this proprietary format is made open.

Max

On Dec 12, 12:59*am, Max Kellermann wrote:
Westbender wrote:
I haven't gotten that far yet. I don't think there's any reason why
the source code can't be released, although I don't know why that
would be important.

For people who don't run 32 bit Windows on an Intel CPU.

For people who don't to run "untrusted" closed-source software.

Practical example: I want to download and verify the flight from the
Cambridge with my Streak running Android. *The Streak has an ARM CPU,
so even if I wanted and even if Windows would run on it, there would
be no chance to use your DLL. *None of my computers runs Windows,
anyway.

The majority of devices sold currently have an Intel CPU, and the
majority of devices sold currently don't run Windows.

If you're not convinced that disclosing and freeing the source code is
important, I can elaborate more.

Max

Downloading a flight from a Cambridge 10/20/25 has nothing to do with
this effort. I am not proposing that, nor am I trying to solution
that. If you're talking about the cai 2 igc conversion process, that
is being done by leveraging the existing vali-cam and conv-cam
utilities from Cambridge. They are currently limited as to what OS
they will run on. I also am not trying to solution any alternatives
for that. I am only trying to provide a solution for 10/20/25 owners
to be able to continue posting their flights on the OLC....period! If
that means it's bound by the same OS limitations that has been in
place up to today for these loggers, then so be it. A limited means is
better than no means. Let's not try to make a mountain out of a mole
hill.

On Dec 12, 12:59*am, Max Kellermann wrote:
Westbender wrote:
I haven't gotten that far yet. I don't think there's any reason why
the source code can't be released, although I don't know why that
would be important.

For people who don't run 32 bit Windows on an Intel CPU.

For people who don't to run "untrusted" closed-source software.

Practical example: I want to download and verify the flight from the
Cambridge with my Streak running Android. *The Streak has an ARM CPU,
so even if I wanted and even if Windows would run on it, there would
be no chance to use your DLL. *None of my computers runs Windows,
anyway.

The majority of devices sold currently have an Intel CPU, and the
majority of devices sold currently don't run Windows.

If you're not convinced that disclosing and freeing the source code is
important, I can elaborate more.

Max

I'm willing to bet that a vast majority of 10/20/25 owners would be
happy to have a new (free) windows-based utility to enable them to
continue posting their flights on the OLC. Untrusted? Sure, you could
say that. Would a flood of apps built by every Tom, Dick and Harry
from open source be any more trusted? Absolutely not!

On Dec 11, 8:43*pm, Marc wrote:
*Personally, I don't understand why the
OLC even bothers validating the files, it's extra work for them, and
it's not like anyone is winning anything except some bragging rights.
Better that all involved understand that it is possible to produce
fake IGC files, and shun those who are caught doing so.


I think we all agree on that. It is unclear to me why OLC still
insisting on the security record. After all, unsecure loggers such as
PDA are allowed, so it is not like they are protecting logger
manufactures. And the security is obvioulsy an illusion, there are
many ways to fake scores on OLC if someone care so much about their
bragging rights. Flights are scored wrongly all the time, usually
unintentionally. If the OLC team does not realize this, it is time to
pull their heads out of their ass. Problem is, they probably don't
care to follow complains on RAS, so I would expect perhaps the US-OLC
Committee to step up to address OLC issues. The SSA web site is
listing one person in the OLC committee but I haven't seen any OLC
related comments from him.
As for the Cambridge issue, the only pilots I know which were still
downloading flights from model 20 loggers are flying selflaunchers
which can not use PDA generated igc file due to missing ENL record. So
my question is why PDAs do not record ENL, either using the ENL data
from the logger if transmitted, or using the PDA mic?

Ramy

Westbender wrote:
I'm willing to bet that a vast majority of 10/20/25 owners would be
happy to have a new (free) windows-based utility to enable them to
continue posting their flights on the OLC.

The vast majority of owners want a solution now, but choosing the best
technical solution often isn't a popularity contest. You would win
that bet, but your bet doesn't matter - Cambridge owners now want a
solution that works now, and today they do not care about the problems
they will face in a few years. Just like in 1996 they didn't care yet
about the problems they face today. I see it as our responsibility
(we = hackers like you and me) to ensure that the next time, the
problem doesn't exist.

Untrusted? Sure, you could say that. Would a flood of apps built by
every Tom, Dick and Harry from open source be any more trusted?
Absolutely not!

That kind of suggestive rhethoric is dull. What does Tom, Dick and
Harry have to do with this?

From your point of view, you are the most trustworthy person in the
world. But that is just your point of view. From my point of view,
you are not, because I don't know you.

From my point of view, all open source developers are more trustworthy
than you, because I can verify that their programs are free of
malware. And I often do.

Max