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Receiving SpaceX Falcon 9 Telemetry with a HackRF and 1.2m Satellite Dish

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Re: Receiving SpaceX Falcon 9 Telemetry with a HackRF and 1.2m Satellite Dish

#31

Post by sandworm101 »

Cthulhu_ wrote: post #18
_Microft wrote: post #6

Some sleuths repaired/decoded a corrupted video file from (the first?) splashdown of a Falcon 9 in the ocean a few years ago [0], so maybe someone is able to tease out some information from the recorded binary data as well? They only searched for obvious string data so far. It's a different beast of course, as the structure and meaning of the data is basically unknown in contrast to the known format of a video file.…

I'm kinda hoping they'll publish some specs about at least part of their transmission data, I mean given that it's not encrypted either means it's not critical, or encryption is too costly. I can imagine that commands the other way do have some kind of encryption.

>> commands the other way do have some kind of encryption.

I'm betting that they don't. The reason that this stuff isn't encrypted is likely the same reason that fighter jets and airliners don't have keys. Yes, someone could jump in and do something bad, but the greater danger is the encryption/lock system causing an accident by getting in the way of legitimate commands. This is the launch vehicle, not the spy satellite.

It is likely that physical realities offer sufficient protection. The rocket might be designed to ignore commands coming from the wrong direction and/or signal strength. It might be that to send a command you would have to be physically co-located with the legitimate antenna array, or be ridiculously more powerful, something that would be very easy to detect.

Re: Receiving SpaceX Falcon 9 Telemetry with a HackRF and 1.2m Satellite Dish

#33

Post by coder543 »

sandworm101 wrote: post #31
Cthulhu_ wrote: post #18

Earlier quoted context omitted.

I'm kinda hoping they'll publish some specs about at least part of their transmission data, I mean given that it's not encrypted either means it's not critical, or encryption is too costly. I can imagine that commands the other way do have some kind of encryption.

>> commands the other way do have some kind of encryption. I'm betting that they don't. The reason that this stuff isn't encrypted is likely the same reason that fighter jets and airliners don't have keys. Yes, someone could jump in and do something bad, but the greater danger is the encryption/lock system causing an accident by getting in the way of legitimate commands. This is the launch vehicle, not the spy satell…

> Yes, someone could jump in and do something bad, but the greater danger is the encryption/lock system causing an accident by getting in the way of legitimate commands.

That's just not how encryption works...

Also, a malicious actor being able to point a multi-ton rocket filled with explosive fuel the wrong direction would be far worse than the system continuing the mission autonomously.

Now imagine human spaceflight missions where the command stream can be hijacked by anyone with an SDR. Yeah, not happening.

The command stream better be authenticated, and if you're doing cryptographic message authentication, you might as well encrypt the payload so no one else can read it anyways.

> The rocket might be designed to ignore commands coming from the wrong direction and/or signal strength.

You want to talk about something error prone "getting in the way of legitimate commands"? That would be an unbelievably error prone approach. Oh, the rocket accidentally rolled on its axis a few degrees? Ignore all commands to correct it!

Encryption and authentication are extremely reliable.

Re: Receiving SpaceX Falcon 9 Telemetry with a HackRF and 1.2m Satellite Dish

#34

Post by dylan604 »

BenjiWiebe wrote: post #11
chrisseaton wrote: post #7

Earlier quoted context omitted.

> This doesn't strike me as particularly sensitive. I'm no rocket scientist but I would have thought you'd want to encrypt and sign everything... by default. Otherwise how do you stop spoofing as well?

Spoofing is extremely difficult when you are pointing a highly directional dish antenna up into the air at a rocket.

Not if you're SR Hadden.

I have been curious on what it would take to do a Contact like signal fake. Would it be possible for a satellite to be launched into a direction in space that for all intensive purpose make it look like it is coming from somewhere else further away? Would it be easy to tell that it is originating much closer than what it is simulating? How far would it need to be away from earth before it was believable, and then would the fact the signal's source is constantly moving futher away be discernible from the signal itself? Basically, think along the lines of a fanfic premise told from Michael Kitz' perspective.

Re: Receiving SpaceX Falcon 9 Telemetry with a HackRF and 1.2m Satellite Dish

#35

Post by shmerl »

mastax wrote: post #21
shmerl wrote: post #15

Does HackRF require soldering an RF shield to it? Apparently it comes without it by default.

No, but you can add it if you want a lower noise floor.

I mean how critical is it? Just an improvement in quality or it's bad without it?

Re: Receiving SpaceX Falcon 9 Telemetry with a HackRF and 1.2m Satellite Dish

#36

Post by Denvercoder9 »

Cthulhu_ wrote: post #18
_Microft wrote: post #6

Some sleuths repaired/decoded a corrupted video file from (the first?) splashdown of a Falcon 9 in the ocean a few years ago [0], so maybe someone is able to tease out some information from the recorded binary data as well? They only searched for obvious string data so far. It's a different beast of course, as the structure and meaning of the data is basically unknown in contrast to the known format of a video file.…

I'm kinda hoping they'll publish some specs about at least part of their transmission data, I mean given that it's not encrypted either means it's not critical, or encryption is too costly. I can imagine that commands the other way do have some kind of encryption.

> that commands the other way

Does Falcon 9 even have a command channel anymore? The trajectory is preprogrammed, guidance and control is automatic, and the flight termination system is automatic as well.

Re: Receiving SpaceX Falcon 9 Telemetry with a HackRF and 1.2m Satellite Dish

#37

Post by jccooper »

Cthulhu_ wrote: post #18
_Microft wrote: post #6

Some sleuths repaired/decoded a corrupted video file from (the first?) splashdown of a Falcon 9 in the ocean a few years ago [0], so maybe someone is able to tease out some information from the recorded binary data as well? They only searched for obvious string data so far. It's a different beast of course, as the structure and meaning of the data is basically unknown in contrast to the known format of a video file.…

I'm kinda hoping they'll publish some specs about at least part of their transmission data, I mean given that it's not encrypted either means it's not critical, or encryption is too costly. I can imagine that commands the other way do have some kind of encryption.

There are no commands the other way. F9 flies entirely autonomous, including termination. Based on the FCC filings, I'm pretty sure it doesn't even have receivers.

Re: Receiving SpaceX Falcon 9 Telemetry with a HackRF and 1.2m Satellite Dish

#38

Post by eeZah7Ux »

Cthulhu_ wrote: post #18
_Microft wrote: post #6

Some sleuths repaired/decoded a corrupted video file from (the first?) splashdown of a Falcon 9 in the ocean a few years ago [0], so maybe someone is able to tease out some information from the recorded binary data as well? They only searched for obvious string data so far. It's a different beast of course, as the structure and meaning of the data is basically unknown in contrast to the known format of a video file.…

I'm kinda hoping they'll publish some specs about at least part of their transmission data, I mean given that it's not encrypted either means it's not critical, or encryption is too costly. I can imagine that commands the other way do have some kind of encryption.

you are confusing encryption and signing

Re: Receiving SpaceX Falcon 9 Telemetry with a HackRF and 1.2m Satellite Dish

#39

Post by ClumsyPilot »

Denvercoder9 wrote: post #36
Cthulhu_ wrote: post #18

Earlier quoted context omitted.

I'm kinda hoping they'll publish some specs about at least part of their transmission data, I mean given that it's not encrypted either means it's not critical, or encryption is too costly. I can imagine that commands the other way do have some kind of encryption.

> that commands the other way Does Falcon 9 even have a command channel anymore? The trajectory is preprogrammed, guidance and control is automatic, and the flight termination system is automatic as well.

People who code still make mistakes. There's got to be an override of some sort

Re: Receiving SpaceX Falcon 9 Telemetry with a HackRF and 1.2m Satellite Dish

#40

Post by fastball »

londons_explore wrote: post #4
robin_reala wrote: post #3

Serbia and Siberia are substantially different places. Let’s hope it’s just a typo and not a bug :)

I really want to visit /S.*ia/ sometime!

Might want to use /S[beir]+a/, otherwise you're gonna end up visiting a famous singer!
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