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ASRR, CASA and ADS-B Why the early implementation??

Are there other problems??

Look at the early implementation of ADS-B in Australia and the extra costs due to the differences in systems. The following posts are interesting on how it works and the problems surrounding early implementation by CASA in Australia.

How it works:

29th Jan 2014, 10:03   #210 (permalink)
Join Date: Aug 2013
Location: PA
Age: 49
Posts: 246
Leadsled, what are you talking about CDMA broadband? ADS-B systems use the 1090 MHz Extended Squitter (1090ES) data link.

First off, the ADS message is limited to 56 bits. The issue has been, how much data from the ac can be braodcast in 56 bits. Note that currently S mode is 56 bits total.

Second, the bandwidth issue is well known, the FAA calls it congestion. Currently, ADSB uses 1090 Mhz, but the FAA is looking at using 978 Mhz below 18,000. Congestion is caused by the bandwidth being used up, and the system will drop aircraft.

Encription, again, well known issue..

“At the Black Hat and Defcon security conference this week in Las Vegas, two security researchers plan to give separate talks on the same troubling issue: By 2020, a new system known as Automated Dependent Surveillance-Broadcast or ADS-B will be required as the primary mode of aircraft tracking and control for commercial aircraft in the U.S.–earlier in other countries such as Australia. And both researchers say that ADS-B lacks both the encryption necessary to keep those communications private and the authentication necessary to prevent spoofed communications from mixing with real ones, potentially allowing hackers to fabricate messages and even entire aircraft with radio tools that are cheaper and more accessible than ever before.

“Anyone can technically transmit these messages,” says Andrei Costin, a Ph.D. candidate at the French security institute Eurecom who plans to give a talk called “Ghosts In The Air (Traffic)” at Black Hat. “It’s practically possible for a medium-technical savvy person to mount an attack and impersonate a plane that’s not there.”

Next-Gen Air Traffic Control Vulnerable To Hackers Spoofing Planes Out Of Thin Air

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30th Jan 2014, 08:10   #215 (permalink)
Join Date: Aug 2013
Location: PA
Age: 49
Posts: 246
Okay, I will bite…I am very aware that there are multiple systems…

I see nothing that shows there is enough bandwidth, as congestion is a well known issue.

I see absolutely nothing that shows any sort of encryption availablity in the data string. It is another well known issue.

So, rather than be cryptic and insultive, why not explain what you are talking about?

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Unread 30th Jan 2014, 09:34   #216 (permalink)
Join Date: Feb 2006
Location: Melbourne
Posts: 975

I’m not an expert, I’ve just read a bit. Others know more.

ADS-B systems use the 1090 MHz Extended Squitter (1090ES) data link.

ES not not universally used. The prime advocate of it is Australia. This is one of the reasons we have trouble getting ADS-B capable transponders.

Also your diagram shows ADS-B in, which Australia is not implementing.

The document that your diagrams come from is 14 years old and is predicated on data transfer speeds of 1 Mb/s. I’d be very surprised if there has not been significant improvement in these speeds which will increase the data capacity.

Congestion depends on the amount of traffic. Australia is the only country in the world that is universally mandating ADS-B for GA IFR aircraft. Other countries implementation varies. Some are by flight type (ie RPT) and some are above an altitude. Only Australia will require all IFR aircraft to use ADS-B.

ADS-B is another example of Australia thinking it has to be different than the rest of the world and the cost of this is borne by aircraft owners.

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