From a4c586a8a14a1edddd425783533602fc963435ed Mon Sep 17 00:00:00 2001 From: Karl Lehenbauer Date: Tue, 19 Aug 2014 11:00:51 -0500 Subject: [PATCH] Update README with FlightAware-specific info. --- README.md | 90 +++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 90 insertions(+) diff --git a/README.md b/README.md index 3fdd396..a3e5029 100644 --- a/README.md +++ b/README.md @@ -1,3 +1,93 @@ +Dump1090 MR README +=== + +Dump1090 MR is a FlightAware fork of Malcolm Robb's fork of +Salvatore Sanfilippo's dump1090 program. FlightAware uses it as an +important element of PiAware (https://adsb/piaware/), a Debian package +for forwarding ADS-B data to FlightAware. + +Salvatore also invented an extremely popular in-memory database called redis, +among other things, and he's pretty busy and doesn't have a lot of time to +jack with dump1090. + +Malcolm split out dump1090's source code out into several different files +and has done steady work maintaining and updgrading it. People have been +sending him patches in the form of pull requests and he's been assiduously +bringing them into the mainline code. + +Although dump1090 is presented primarily as an ADS-B (Mode S) decoder +specifically designed for these little RTLSDR USB dongles that contain +a software defined radio and FPGA and were originally intended for decoding +certain satellite TV broadcasts, dump1090 can do many other useful things +such as +* decode and interpret ADS-B messages from various formats +* Stream ADS-B messages in various formats using Internet-standard TCP sockets +* provide a web interface to show aircraft traffic on a map in real time +* and more + +Since airborne aircraft transmit their positions twice each second, ADS-B +receivers located in high traffic areas can receive as many as thousands +of messages each second. + +Much of this information can be filtered out without a significant loss +of fidelity at the receiving end. For example, an aircraft flying at +a high altitude with a consistent heading and speed, the aircraft's +location information can be forwarded less frequently. + +Also aircraft equipped with legacy transponders, as most still are, only +their altitude is being transmitted, not their latitude and longitude, etc, +and as these messages aren't as useful they don't need to be sent as often. + +The FlightAware fork leverages dump1090 to create a new message format +that is filtered as described above plus with additional criteria +and then we group multiple messages together into a single TCP packet +to reduce overhead (as each IPv4 packet has a 64-byte header), +ultimately requiring a small fraction of the bandwidth used by the other +data formats dump1090 can send natively. This is on port 10001 by default. + +Within the dump1090 repo also is a program called faup1090. When someone +is running their own dump1090 or native Malcolm Robb dump1090, faup1090 +can connect to dump1090, interpret the packets it receives, and translate +them into the same filtered format our fork of dump1090 produces. + +FlightAware's PiAware Debian package (https://flightaware.com/adsb/piaware/) leverages either faup1090 or dump1090 +with additional software to connect to FlightAware with a compressed, +encrypted TLS connection, log in using your FlightAware account and +password, and forward your ADS-B data, where it is collected as part of +FlightAware's worldwide network of Airspace National Service Providers, +satellite tracking providers, networks of ADS-B providers, our FA-managed +ADS-B network. + +By contributing your ADS-B data to FlightAware you +* contribute to the accuracy of FlightAware's flight tracking, almost all of which is available for free worldwide through the FA website in 15 languages +* gain the ability to see a realtime picture of all ADS-B traffic FlightAware knows about +* make the Internet itself more useful +* help people communicate and share information + +Every day hundreds of thousands of people save time and energy using +FlightAware. If someone leaves for the airport an hour later because the +flight they're meeting is an hour late, they got an hour of their life +back, and that's an hour not spent in their car with the engine running +or whatever. It's a win for the person, a win for the environment, and +your contribution to that is real and genuine. + +While doing this, FlightAware in no way restricts your ability to share your +ADS-B data with other flight trackers. + +Most people will have no need to grab dump1090/faup1090 from source code and +build it. If you already have dump1090 running with some sort of ADS-B +receiver, all you need to send stuff to FlightAware is to install our +Debian package and configure it with your user name and password. + +But for the intrepid, here is the source code, in all its glory, freely +redistributable under the permissive Berkeley copyright, modifiable for +your use and others, including for profit, should you desire. + +We will continue to track the Malcolm Robb fork of dump1090 for the +foreseeable future and maintain our modifications. We solicit any bug +reports and bug fixes are, as always, for the same. + + Dump1090 README ===