ADSB data on now viewable on the OGN

[Davis Chappins]

With the discussion about OGN data happening in another thread, now is a good time to say that I have been forwarding ADSB locations to the OGN.

It's running on my raspberry pi at home alongside the SPOT/Inreach to OGN scripts.
I have been running it since Feb and seems to be working well.

Why did I do this? I got bored last year and wanted to do a project in python to learn the language more and this sounded like fun.

How will you know if the position is from ADSB or FLARM? Some OGN websites will show the receiver detecting the aircraft (or source of the data), "ADSBExch" is visible in that field when the position is coming from ADSB data.

How does it work?
This script connects to an ADSB API (for ADSB positions) and the OGN (for FLARM positions). The script listens to both sources and manages a traffic list composed of each unique aircraft's position, speed, altitude, etc from both sources.

If a glider position exists from ADSB and not from FLARM, that glider's position is pushed to the OGN from the ADSB source.
If a glider position exists from both ADSB and FLARM, that glider's ADSB position will only be pushed to the OGN when the FLARM source is 120 seconds older than the ADSB source. Thereby seamlessly transitioning between the high refresh rate FLARM position and a lower refresh rate but larger ranged ADSB position.

To be seen, you will need to have a Mode S (non ADSB and be within MLAT range) or a Mode S (with ADSB) transponder. The script is set up to run on my pi from 9a to 8p MST, 7 days a week. And at the moment it is only set up to scan the North American lat/lon range.

The API is queried at 10 second intervals then the valid positions are sent to the OGN. For tracking, the signal has a refresh rate of somewhere between 5 and 15 seconds. A much lower resolution than the OGN's 1-2 second position intervals but ADSB has a much larger range.

[John Godfrey]

Outstanding!

[Charles Gillespie]

Hi Davis, cool project. Do you know if the pushed ADSB targets create duplication with existing FLARM targets on OGN displays?

Charlie

[Bruce]

Quoted from Davis's original message

[Charles Gillespie]

I can see that to be true. I was watching a couple of gliders doing airwork at Boulder on GlideandSeek and GliderRadar. One of our club gliders which has ADSB and a FLARM registered on OGN, toggles between OGN and ADSBExch as its receiver source while in the air (within line of sight to OGN receiver) and exclusively ADSBExch while on the ground (when it drops below line of sight to OGN receiver). The other glider from the nearby commercial operation shows ADSBExch both on the ground and in the air, suggesting that it has ADSB and and no FLARM equipped, or has a FLARM which is not registered to OGN. Good stuff!

[Davis Chappins]

https://i.imgur.com/808hJkM.png

Last Saturday had about 50 ADSB gliders being forwarded to the OGN, which is cool.
This python script continues to run on my pi at home. If anyone knows of a more professional hosting, feel free to reach out.

[Philip Lee]

I moved some of my OGN/python scripts to AWS without issue couple of years ago. Costs about $10/mo.

[Davis Chappins]

All,
If you have a Mode S (non ADSB) transponder in your glider you will show up on the OGN via my ADSB script. If you also equip your Mode S glider with an OGN Tracker, two targets will show up! One from Mode S and one from the OGN Tracker. This is undesirable.

This issue does not occur with ADSB equipped and FLARM equipped gliders because the icao IDs are the same. In the case of Mode S + OGN Tracker the icao IDs are different (the OGN Tracker has its own id that is not linked in any way to the N number of the aircraft).

To prevent this issue I have created a "black list" of icao IDs and N numbers that suppresses those ADSB positions leaving only the OGN Tracker position.

So,
If you equip your glider with an OGN Tracker and now see two positions on the OGN, add your glider to OGNTrackerBlackList.csv at https://github.com/DavisChappins/ADSBtoOGN to fix it. This list is updated once a day at 4am PST so changes will not take effect until the next day.

[Moshe Braner]

How many people are using a pure "OGN tracker"? If one is using the
SoftRF software then it does allow one to enter the aircraft ICAO ID, to
be used instead of the device ID, same as is done with a FLARM.

[Davis Chappins]

Good question.

In this thread OGN Tracker = softrf.

My understanding is that the device ID is fixed and unable to be changed like FLARM. If it is able to be changed I am unfamiliar with how it works. https://github.com/lyusupov/SoftRF/wiki/Settings
I am using the rev 1.1 firmware that comes preloaded.

[Davis Chappins]

Unfortunately my API key has expired, apparently it had a 1yr life.
Until I can secure a working key no ADSB data will be forwarded to the OGN.

[Davis Chappins]

So good news I was able to find an API from flightradar24 and adapt my script to pull from that. I took the time to improve it and now it tracks by ICAO type https://www.icao.int/publications/doc8643/pages/search.aspx instead of squawk. This means it does track gliders on the ground.

I have the following ICAO types covered: GLID,S10S,S12S,LK17,AS25,AS26,AS24,A32P,AS28,A33P,A33E,AS30,AS31,DISC,NIMB,ARCP,ARCE,VENT,VNTE,JS1J,JS2J,JS2P,JS3J,JS3E,EB29,U15,DIMO,RF10
Am I missing any?

I also improved the timing of the API requests and it will wait longer and longer to ping the API depending on the gap between valid ADSB signals.


I am unsure about how many API requests I can do in a 24hr period from my IP before flightradar24 starts denying my requests so I'd like to host this on the cloud. Maybe several instances that have different IPs that could run at the same time....Does anyone have any experience doing this?

[Dan Marotta]

Would a VPN masking your IP address be beneficial? I know that I get
three times the bandwidth at home when I turn on my VPN.

Dan
5J

On 1/22/23 20:50, Davis Chappins wrote:
> snip

[Davis Chappins]

Dan,
Good idea. I do have a 2nd pi lying around and signed up for a vpn on that pi.
Now that 2nd one is also running the same ADSB forwarding script as the first one, from a separate IP. I have been making about 2000 API calls per 24h and have not yet been blocked. For reference the website will do the same every 5s if left open.

If you are looking on glidertracker.org or similar and see the signal source as ADSBfr24 or ADSBFR24 the source is flightradar24 ADSB.

[david.s....@gmail.com]

how does the speed improvement come about? Do the messages somehow take a more efficient route? Offhand one might expect a less efficient route since an extra hop is required to go from the VPN to your real IP address.

I'm not doubting that this result has been observed but am genuinely curious and hoping to learn more.

Thanks,
...david

[Davis Chappins]

David,
What do you mean by "speed improvement"?

[david.s....@gmail.com]

On Friday, January 27, 2023 at 9:28:10 AM UTC-5, davis.c...@gmail.com wrote:
> David,
> What do you mean by "speed improvement"?

Davis,

Sorry, I should have quoted other text. I was replying to Dan M.'s comment that using a VPN gives him a 3x bandwidth improvement.

Cheers,
...david

[Dan Marotta]

I'm not up on VPN technology but the vendor, NordVPN, in my case says
that they bypass my ISP's servers altogether. I can't see how they
could do that, since my ISP connects the wire to my house, which
connects to a fiber in the service box in the neighborhood, which I
would assume, connects to their servers.

But the fact remains that, when using an internet speed test program on
my laptop and on my TV (through Amazon FireTV 4K) the results are
noticeable. Here are some numbers:

Visio TV using Amazon FirTV 4K Stick
With VPN
download @ 56.84 Mbps, upload @ 10.91 Mbps
download @ 149.07 Mbps, upload @ 21.05 Mbps

Laptop, Asus, Ubuntu Linux 22.04 64-bit
Without VPN download @ 76.07 Mbps, upload @ 9.67 Mbps
With VPN download @ 78.9 Mbps, upload @ 10.09 Mbps


It would appear that it doesn't make much difference on my laptop, but a
huge difference on my TV as evidenced by buffering at times without the
VPN but not with it turned on. The TV runs an Android operating system
which may also contribute to it's much improved performance using the VPN.

Dan
5J

[Martin Gregorie]

On Fri, 27 Jan 2023 13:04:05 -0700, Dan Marotta wrote:

> I'm not up on VPN technology but the vendor, NordVPN, in my case says
> that they bypass my ISP's servers altogether. I can't see how they
> could do that, since my ISP connects the wire to my house, which
> connects to a fiber in the service box in the neighborhood, which I
> would assume, connects to their servers.
>

Interesting.

Does the path a packet takes to reach a target destination from your
laptop, differ depending on whether VPN is on or off?

It would be worthwhile to see if 'traceroute' shows ant differences: it is
a toool that shows the route a probe message sent by it takes across
t'interwebs, so sending the probe to the same destination with VPN on and
then off should clearly show whether the path the probe message takes
depends on the VPN setting, and *may* also show time-of-flight
differences (provided they don't just get lost in Internet traffic queues,
and switching delays).





--

Martin | martin at
Gregorie | gregorie dot org

[Charlie M. (UH, Pi & 002 owner/pilot)]

In older Windows (not sure above XP pro....sigh....) you are looking at a "traceroot"?

[Martin Gregorie]

On Fri, 27 Jan 2023 19:09:38 -0800 (PST), Charlie M. (UH, Pi & 002
owner/pilot) wrote:

> In older Windows (not sure above XP pro....sigh....) you are looking at
> a "traceroot"?
>

I suggested 'traceroute' because I noticed that Dan, like myself, is using
Linux.

[Dan Marotta]

That would be interesting to try, Martin, but it's above my software
paygrade. Perhaps you could supply the complete command? I have it
installed but am not having success with working it.

If you use a proper (read old fashioned) news reader, you should have my
email address...

Dan
5J

[Dan Marotta]

...Cuz Windows drives me batshit crazy. I'm still trying to stop the
(multiple) daily notifications I receive on my phone that my "Windows
account needs attention." I haven't used Windows in a long time and I
finally tried cancelling the account. Best they would do was say that
it would be cancelled in 30 days if I didn't change my mind. Still
waiting...

Dan
5J

[Mark Mocho]

"Cuz Windows drives me batshit crazy. "

Windows is the world's best-selling virus.

[Martin Gregorie]

On Sat, 28 Jan 2023 10:01:48 -0700, Dan Marotta wrote:

> That would be interesting to try, Martin, but it's above my software
> paygrade. Perhaps you could supply the complete command? I have it
> installed but am not having success with working it.
>

From the command line its a single line command: "traceroute hostname",
for instance, to try it against one of my domain names, run this to see
what it does,

traceroute libelle-systems.com

Two Linux tips:
===============
"man commandname" tells you everything you need to know about a command by
displaying its 'manpage', i.e. its manual page

"apropos 'a word or phrase'" searches the first, summary, line of all the
manpages on your system and shows a list of
matches. On a Linux/UNIX system every
standard program or library function has a
manpage, so this is 'apropos' a v. useful

[Dan Marotta]

Martin,

Well, it looks backwards to me. Here is the output from the trace route
command with VPN disconnected. I recognize my IP address (blotted out):


traceroute to libelle-systems.com (3.33.152.147), 64 hops max
1 xxx.xx.xx.xx 1.283ms 0.903ms 1.207ms
2 67.42.200.51 26.118ms 26.358ms 25.863ms
3 67.42.136.97 26.088ms 25.866ms 25.687ms
4 99.82.183.2 33.994ms 32.938ms 33.157ms
5 52.93.74.36 34.406ms 33.729ms 33.717ms

And here it is with the VPN connected:

traceroute to libelle-systems.com (3.33.152.147), 64 hops max
1 10.5.0.1 32.298ms 32.149ms 32.618ms
2 83.136.182.3 32.116ms 32.825ms 32.225ms
3 62.115.186.14 32.947ms 32.936ms 33.037ms
4 213.248.75.245 32.402ms 32.706ms 32.261ms
5 209.120.154.162 50.908ms 51.963ms 51.644ms
6 150.222.206.215 52.287ms 52.505ms 52.384ms

Can you explain this?

Dan
5J

On 1/28/23 16:21, Martin Gregorie wrote:
> traceroute libelle-systems.com

[Matthew Scutter]

Bravely going well off thread to answer David's questions...

VPN's are in most cases snake oil - they typically purport to increase your security through 'encryption', but in reality they just move the unencrypted bit from your computer to some random unaccountable server in a far-off land. In general I cannot recommend them.
You may also get worse service from websites unable to geolocate you correctly (i.e. SkySight, to put the location dot).

So we go from;
Your Computer <--unencrypted, if not using SSL i.e. padlock symbol--> Your destination

And instead get;
Your Computer <--encrypted--> Unaccountable Server <--unencrypted, if not using SSL i.e. padlock symbol--> Your destination

Adding this extra stop at Unaccountable Server almost always adds distance/latency and the resulting 'speed' as it appears to the end user will be lower.

There are a few circumstances where this is not the case. Your data doesn't necessarily flow along the fastest possible path from A to B, more typically it flows across the most economical path/'peering' for your ISP. This is often but not always the fastest.

If your VPN provider is colocated at or at a location your ISP has fast connectivity to, and your VPN provider also pays for fast connectivity from itself to your destination, it could be faster. Cloudflare WARP+ for example puts servers with most ISP's, and then (claims to) pay a premium for peering faster than your ISP might be paying.

I tested this to be true in Cloudflare's case but also found a small number of websites that broke and bugs/crashes in the Cloudflare software that lead to inexplicable network dropouts.

In summary, the security claims are largely a scam, and you're more likely to see better performance from choosing a more expensive/reputable ISP that pays more for faster paths/peering. If you don't have a choice of ISP and it solves a problem for you, do what you have to do...

[Martin Gregorie]

What Matthew said, but also note that there's nothing in the way the
Internet works that says that your laptop and your TV dongle have to
connect to the same box at the end of the first hop to end outside your
house: the device that connects stuff inside your house to the the
physical external network, commonly referred to as being or containing a
firewall, is itself a router and, while it may have been configured to
talk to your ISP, there's nothing to say that something else in your house
(such as a TV dongle) can't tell it to connect elsewhere, such as to a
VPN. The only restriction it *should* have is to refuse redirection
requests from outside (though some el-cheapo units will accept them).

FWIW I have my house's gateway router configured to be invisible from the
outside.

[Frank Whiteley]

There have been instances (and apparently still are) where specific services were being throttled at edge routers and VPN tunnels were able to improve performance substantially. I haven't done much testing recently but my VPN service with a static IP attached seems to be rate limited to 50Mbps for the servers I connect with. Haven't tested other portals with dynamic IP's, but may have to do that.

Frank