6 ms·

I feel that this data is trade secret - why it is not encrypted?

by ex3ndr 6y ago

gmueckl 6y ago
Looks like this is just data from the GPS receiver, mostly about where the rocket thinks it is at the moment. This doesn't strike me as particularly sensitive. Data from, say, sensors embedded in the engines would be much more interesting.
- chrisseaton 6y ago
  > 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?
  - verelo 6y ago
    Encryption takes time, and energy. I suspect they are trying to avoid adding latency to anything that’s not super sensitive.
    - mikepurvis 6y ago
      Those final gasps of data while a vehicle is breaking up could be critical for understanding what went wrong with it. I can definitely see how missing out on the final milliseconds of telemetry because some encryption buffer wasn't full enough to trigger a frame or something would be unacceptable.
      - myself248 6y ago
        I think this is the true reason that telemetry is as raw as possible. The happy-path telemetry tells you very little you didn't already know, but when something goes wrong, those last few bits before the transmitter went silent can make or break your analysis. Sitting on bits until you have enough to run a block through the cipher seems like a terrible idea, even if that's only a few microseconds. Things happen mighty fast when you're trying to get data that might represent the structural collapse or propagation of a blast wave through the body of a hypersonic vehicle.
      - vardump 6y ago
        You don't need any buffering if you pick your encryption mode correctly. That is, use a stream cipher.
        mikepurvis 6y ago
        How much would that affect the ability to recover a partially-corrupted stream, though? I feel like that's part of this too— where the last few seconds might have an increasing amount of the content scrambled, and encryption would render that completely unusable, whereas having it in plaintext would still permit some degree of inference about the fragments you do have.
        vardump 6y ago
        It would not affect at all. Flipped bits / transmit errors have no avalanche effect, unless the bit was flipped in the encryption module.
        mikepurvis 6y ago
        What if you have gaps in your stream with uncertain length, though? Based on quick read about stream ciphers, it seems like the alignment of the key and data is pretty critical.
        vardump 6y ago
        Might be some truth here. Although at this point automatically interpreting plain text data would fail as well. In both cases, you could add separating symbols in the raw data stream. Also, timing should help here. Sure there can be gaps, but at a given data rate the receiving end should be able to compensate for it, as long as velocity doesn't have large unexpected changes (doppler). Even then it should be decodable afterwards. There are a lot of ways you can compensate for any of these issues. That said, of course plain text is going to be the easiest option for a human to decode when everything else fails.
      - Rebelgecko 6y ago
        I think this is a very plausible reason. After a F9 blew up in 2016 or so, the NASA accident review even threw a little bit of shade because the telemetry right before the explosion was lost to bufferbloat
  - toomuchtodo 6y ago
    I can't speak to SpaceX's decision, but in FCC rulings, they have proposed encryption when commanding vehicles, not for telemetry or tracking comms (satellites, specifically, although I'd assume similar guidance for vehicles, with the only command you're going to send to the vehicle would be boom for range safety).
    - toomuchtodo 6y ago
      For historical purposes, range safety on SpaceX vehicles has been autonomous and onboard since 2017. Vehicles emit telemetry, but do not receive commands. https://www.spaceflightinsider.com/space-centers/ccafs/automated-flight-safety-improving-space-access/ https://www.spaceflightinsider.com/space-centers/ccafs/autom...
  - BenjiWiebe 6y ago
    Spoofing is extremely difficult when you are pointing a highly directional dish antenna up into the air at a rocket.
    - dylan604 6y ago
      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.
      - sandworm101 6y ago
        >> 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? Anything is possible but it would be very hard. You would have to fake the doppler shifts. With massive scrutiny you might even have to fake some absorption lines. Then, if the signal was longer than a few days/weeks, you would need to place the emitter far enough away that parallax, relative motion against the stellar background, was undetectable. That distance is probably measured in light-years.
- rrmm 6y ago
  If they were carrying a national security payload, then having a gps feed of the second stage trajectory and target orbit would be less than ideal.
  - ceejayoz 6y ago
    Amateur astronomers are very good at spotting national security payloads after launch. https://www.theatlantic.com/technology/archive/2016/06/mapping-clandestine-moons/485915/ https://www.theatlantic.com/technology/archive/2016/06/mappi...
    - rrmm 6y ago
      Yup. Easy to do for most adversary nation-states as well, but the NRO still doesn't allow the SpaceX livestream to follow stage 2.
      - _Microft 6y ago
        Maybe it's possible to detect radio echoes off the rocket exhaust trail (passively) like it is possible to do with meteors [0][1] and roughly tell where the second stage is (just for the sake of doing it this way). [0] https://www.electronics-notes.com/articles/antennas-propagation/meteor-scatter-burst-communications/meteors-trails-radio-signals.php https://www.electronics-notes.com/articles/antennas-propagat... [1] https://en.wikipedia.org/wiki/Meteor_burst_communications https://en.wikipedia.org/wiki/Meteor_burst_communications
      - ceejayoz 6y ago
        Yeah, over-classification is definitely a thing. I suspect they don't want close-up video imagery of the payloads out there, either.
    - Cthulhu_ 6y ago
      And if amateur astronomers can do it, a well-funded national space agency can do it even better. I'm 100% sure that any launch is picked up via radar and sattelites and the like when they happen, and various properties extracted and extrapolated to determine their target orbit. That said, I wouldn't be surprised if some known launches also contained some unknown payloads. Stealth technology on a satellite would probably thwart detection in space well enough.
ylere 6y ago
People have been running full simulations of SpaceX vehicles just of on-screen telemetry and videos [0]. In the past, SpaceX has been very open towards these kind of efforts, they don't seem to mind at all. [0] Example for SN9: https://www.youtube.com/watch?v=UeBtBidjlvk https://www.youtube.com/watch?v=UeBtBidjlvk | https://flightclub.io/result?code=SN91 https://flightclub.io/result?code=SN91
magicalhippo 6y ago
I imagine it adds latency, which at the very least means more data is lost in case of accident, which can make it harder to know what went wrong. It also adds an additional failure point, as a single bit error during encryption can scramble an entire data packet or worse, rather than just invalidating a single sensor reading.
- de6u99er 6y ago
  You can do this with FPGAs in real-time. https://www.google.com/search?q=fpga+encryption+serial+data+real+time https://www.google.com/search?q=fpga+encryption+serial+data+...
cedivad 6y ago
This is just a guess, but having read the FCC regs in the past, maybe it's because it's so much easier to be complaint when your link is unencrypted (and your rf standard published).

I feel that this data is trade secret - why it is not encrypted?

by ex3ndr 6y ago

I feel that this data is trade secret - why it is not encrypted?

Looks like this is just data from the GPS receiver, mostly about where the rocket thinks it is at the moment. This doesn't strike me as particularly sensitive. Data from, say, sensors embedded in the engines would be much more interesting.

chrisseaton 6y ago
> 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?
- verelo 6y ago
  Encryption takes time, and energy. I suspect they are trying to avoid adding latency to anything that’s not super sensitive.
  - mikepurvis 6y ago
    Those final gasps of data while a vehicle is breaking up could be critical for understanding what went wrong with it. I can definitely see how missing out on the final milliseconds of telemetry because some encryption buffer wasn't full enough to trigger a frame or something would be unacceptable.
    - myself248 6y ago
      I think this is the true reason that telemetry is as raw as possible. The happy-path telemetry tells you very little you didn't already know, but when something goes wrong, those last few bits before the transmitter went silent can make or break your analysis. Sitting on bits until you have enough to run a block through the cipher seems like a terrible idea, even if that's only a few microseconds. Things happen mighty fast when you're trying to get data that might represent the structural collapse or propagation of a blast wave through the body of a hypersonic vehicle.
    - vardump 6y ago
      You don't need any buffering if you pick your encryption mode correctly. That is, use a stream cipher.
      - mikepurvis 6y ago
        How much would that affect the ability to recover a partially-corrupted stream, though? I feel like that's part of this too— where the last few seconds might have an increasing amount of the content scrambled, and encryption would render that completely unusable, whereas having it in plaintext would still permit some degree of inference about the fragments you do have.
        vardump 6y ago
        It would not affect at all. Flipped bits / transmit errors have no avalanche effect, unless the bit was flipped in the encryption module.
        mikepurvis 6y ago
        What if you have gaps in your stream with uncertain length, though? Based on quick read about stream ciphers, it seems like the alignment of the key and data is pretty critical.
        vardump 6y ago
        Might be some truth here. Although at this point automatically interpreting plain text data would fail as well. In both cases, you could add separating symbols in the raw data stream. Also, timing should help here. Sure there can be gaps, but at a given data rate the receiving end should be able to compensate for it, as long as velocity doesn't have large unexpected changes (doppler). Even then it should be decodable afterwards. There are a lot of ways you can compensate for any of these issues. That said, of course plain text is going to be the easiest option for a human to decode when everything else fails.
    - Rebelgecko 6y ago
      I think this is a very plausible reason. After a F9 blew up in 2016 or so, the NASA accident review even threw a little bit of shade because the telemetry right before the explosion was lost to bufferbloat
- toomuchtodo 6y ago
  I can't speak to SpaceX's decision, but in FCC rulings, they have proposed encryption when commanding vehicles, not for telemetry or tracking comms (satellites, specifically, although I'd assume similar guidance for vehicles, with the only command you're going to send to the vehicle would be boom for range safety).
  - toomuchtodo 6y ago
    For historical purposes, range safety on SpaceX vehicles has been autonomous and onboard since 2017. Vehicles emit telemetry, but do not receive commands. https://www.spaceflightinsider.com/space-centers/ccafs/automated-flight-safety-improving-space-access/ https://www.spaceflightinsider.com/space-centers/ccafs/autom...
- BenjiWiebe 6y ago
  Spoofing is extremely difficult when you are pointing a highly directional dish antenna up into the air at a rocket.
  - dylan604 6y ago
    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.
    - sandworm101 6y ago
      >> 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? Anything is possible but it would be very hard. You would have to fake the doppler shifts. With massive scrutiny you might even have to fake some absorption lines. Then, if the signal was longer than a few days/weeks, you would need to place the emitter far enough away that parallax, relative motion against the stellar background, was undetectable. That distance is probably measured in light-years.
rrmm 6y ago
If they were carrying a national security payload, then having a gps feed of the second stage trajectory and target orbit would be less than ideal.
- ceejayoz 6y ago
  Amateur astronomers are very good at spotting national security payloads after launch. https://www.theatlantic.com/technology/archive/2016/06/mapping-clandestine-moons/485915/ https://www.theatlantic.com/technology/archive/2016/06/mappi...
  - rrmm 6y ago
    Yup. Easy to do for most adversary nation-states as well, but the NRO still doesn't allow the SpaceX livestream to follow stage 2.
    - _Microft 6y ago
      Maybe it's possible to detect radio echoes off the rocket exhaust trail (passively) like it is possible to do with meteors [0][1] and roughly tell where the second stage is (just for the sake of doing it this way). [0] https://www.electronics-notes.com/articles/antennas-propagation/meteor-scatter-burst-communications/meteors-trails-radio-signals.php https://www.electronics-notes.com/articles/antennas-propagat... [1] https://en.wikipedia.org/wiki/Meteor_burst_communications https://en.wikipedia.org/wiki/Meteor_burst_communications
    - ceejayoz 6y ago
      Yeah, over-classification is definitely a thing. I suspect they don't want close-up video imagery of the payloads out there, either.
  - Cthulhu_ 6y ago
    And if amateur astronomers can do it, a well-funded national space agency can do it even better. I'm 100% sure that any launch is picked up via radar and sattelites and the like when they happen, and various properties extracted and extrapolated to determine their target orbit. That said, I wouldn't be surprised if some known launches also contained some unknown payloads. Stealth technology on a satellite would probably thwart detection in space well enough.

ylere 6y ago

People have been running full simulations of SpaceX vehicles just of on-screen telemetry and videos [0]. In the past, SpaceX has been very open towards these kind of efforts, they don't seem to mind at all. [0] Example for SN9: https://www.youtube.com/watch?v=UeBtBidjlvk https://www.youtube.com/watch?v=UeBtBidjlvk | https://flightclub.io/result?code=SN91 https://flightclub.io/result?code=SN91

magicalhippo 6y ago

I imagine it adds latency, which at the very least means more data is lost in case of accident, which can make it harder to know what went wrong. It also adds an additional failure point, as a single bit error during encryption can scramble an entire data packet or worse, rather than just invalidating a single sensor reading.

de6u99er 6y ago
You can do this with FPGAs in real-time. https://www.google.com/search?q=fpga+encryption+serial+data+real+time https://www.google.com/search?q=fpga+encryption+serial+data+...

cedivad 6y ago

This is just a guess, but having read the FCC regs in the past, maybe it's because it's so much easier to be complaint when your link is unencrypted (and your rf standard published).