3 ms·
Have you ever found interesting/unexplained data in the packet streams? I know there's provision for traffic stuff in there, and a few other defined types, but
by myself248 3y ago
Have you ever found interesting/unexplained data in the packet streams? I know there's provision for traffic stuff in there, and a few other defined types, but what else is hiding?
Reason I ask, is analog FM had all sorts of sideband streams for the longest time, like SCA audio and DirectBand digital, that weren't well known at the time. And while internet access is certainly easier to get these days, there might still be a justification for one-way data broadcasts in certain applications, so I wonder if someone's out there leasing subchannels or sub-packet-IDs or what-not, and shuffling encrypted data around in them.
- argilo 3y agoSome stations have "HD TMC" (traffic message channel) streams. The others that I've encountered are "HERE Images" (traffic & weather radar images, discussed and mostly reverse engineered in https://github.com/theori-io/nrsc5/pull/308 https://github.com/theori-io/nrsc5/pull/308), "HERE TPEG", "TTN TPEG", "TTN STM", "NavteqAdmin" and "NavteqPacketData1." At present, nrsc5 makes these streams available through its API, but doesn't otherwise do anything useful with them. I don't believe any of the GUIs process them either. Some reverse engineering work is needed.
- argilo 3y agoAlso, all of those stream types seem to be used across multiple stations. I haven't seen any weird one-off streams.
- patja 3y agoThere was the somewhat recent issue in Seattle where a station included an image file with no file extension, and it bricked the radios in Mazdas: https://arstechnica.com/cars/2022/02/radio-station-snafu-in-seattle-bricks-some-mazda-infotainment-systems/ https://arstechnica.com/cars/2022/02/radio-station-snafu-in-...