EDDF4 please PM to me

[controller]

Hy,

my RADAR is T-EDDF2, I found out because we cover both EDDF but we mix our flight data. So planes jump forward an backward dependig of the RADAR that supplies data.

Maybe he has the problem like me when I used the old upload software. I changed now to the new, better one.

Ralph

[VTBS-1-2-3]

This topic interests me. I would like to know how the server handles it if multiple radars feed the same flight but the data is different.

Does the server "vote" on which feeder(s) to trust more ? How can we guard against a malicious feeder uploading manipulated data ?

[Oblivian]

It's based on data timestamp.

Old feeder captures 10second sample, bundles it, send to server. Server receives, and then unpacks and displays on map. Giving a position based on the time it received the newest location. If you have your clock out (everyone feeding should be using a replacement NTP service to keep clock correct to ~8ms) then the data can appear at the wrong position location as it flicks back to other uploaders with correct time as it appears 'newer' but the positions may not be.

New feeder, uses ADSB timestamp in the data uploaded. So is more accurate to location. When overlapping old/new feeders are near each other. The server will perfer the newer uploader data as it has a later timestamp. But if for whatever reason it switches to the data from the old uploader, the position could be up to 10seconds behind where it last was. Causing it to appear to go back and forth 10second jumps.

Make sense?

Mike has said in the past, once all uploaders are migrated the issue should be resolved. However if people have chaged email address from when registering as an uploader, and do not read forums they may not see the message to upload and where to download it from

Their only notification will be when the old data receive port is shut down.

[controller]

Hello Oblivian,

yes are are right, thats the reason why I want to reach EDDF4 in order to tell him that he should change upload software.

I dont think that anybody fakes data.

Ralph

[VTBS-1-2-3]

Hello Oblivian,

I dont think that anybody fakes data.

Neither do I. Just curious how data integrity is assured. So the people who have the current feeder app, they show as T-XXXX whereas old ones would show as NET-X or XXXX ?

[Oblivian]

http://forum.flightradar24.com/threads/3650-Difference-Between-Radars?p=16915&viewfull=1#post16915