If You've Flown a FLARM Stealth Contest, Vote Here

On Tue, 15 Dec 2015 08:58:19 -0800, Andy Blackburn wrote:

Stealth information masking is implemented on the receive end, but AFAIK
it works like this: If you configure stealth no one, regardless of their
setting will see anything but the information designated in the stealth
spec (2km range except for active alarms, no climb or ID, etc). In
addition your display will only receive information on ALL other
gliders (regardless of their configuration stealth) as specified in
the stealth spec.

I have a hazy recollection that this came in with V5.0 softwa prior to
that all data was transmitted along with the 'stealth' flag that caused
the *receiver* to operate in stealth mode, and that the OGN developers
ignored the stealth flag so that FLARM-radar networks showed all FLARM-
carrying aircraft. IIRC a lot of pilots objected to OGN ignoring the
stealth flag and refusing to honour its settings and claiming freedom of
information reasons for doing this. Since OGN had apparently reverse-
engineered the protocol rather than talking nicely to FLARM, the latter
got ****ed off with this and took V5.0 release as an opportunity to
remove stealthed data/encrypt the message. This forced OGN to play nicely
with FLARM and lead to the current way that stealth works.

At least, thats what I remember happening around the time that the V5.0
software was released.


--
martin@ | Martin Gregorie
gregorie. | Essex, UK
org |