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Using encryption on ham bands is illegal yes. You can use it on commercial bands if you buy a license from the FCC and ISM (common 2.4ghz/5Ghz) is mostly fair g

Using encryption on ham bands is illegal yes. You can use it on commercial bands if you buy a license from the FCC and ISM (common 2.4ghz/5Ghz) is mostly fair game as well. The practical reality is people are probably getting away with abusing it because the FCC is not omniscient and has limited resources. For an individual to draw the ire of the FCC they need to make a nuisance of themselves. Occasionally you hear of people getting arrested for using illegal cell jammers and the like. I can't recall hearing of someone getting caught using encryption. For something like this to really get a crackdown you would need a watershed event like RC aircraft had with cheap drones. The point where very capable hardware became extremely cheap and accessible to people who know nothing about the hobby. The RC aircraft community effectively self policed for decades because the bar for entry was high enough that anyone getting involved had to engage with the community. Drones changed that. And the FAA had to step in and regulate. I think we are getting close with cheap Chinese radios. But even Baofengs still require programming and educating yourself. Devices like the flipper zero are far more damaging. Even though they are limited in their capabilities, they make it trivial for the user to make a nuisance of themselves in ways that are hard to ignore. Its probably a matter of time until a cheap radio hits Amazon that does everything for you and permits non hobbyists to ruin everything. Imagine something as capable as a HackRF but as easy to use as an iPhone. Then we have problems.

reaperman 3y ago
Assuming there was aggressive enforcement against it, could someone “get away” with encrypted transmission sent in low-power alongside high-power unencrypted transmissions? Like would a well-encrypted stream look indistinguishable to a bit of noise from a low-quality transceiver?
- thereddaikon 3y ago
  That depends entirely on what they are listening with. One sub set of ham radio is called fox hunting which is a gameified form of radio direction finding. Some guys are really good at it. If you annoy one of them and they are persistent they can potentially track you down. The Feds of course have very sophisticated tools far and above what's available to you but if you've drawn that kind of attention you are already in deep trouble and looking at jail time. Powerful software defined radios like the RTL-SDR are inexpensive and with a PC can be used to scan broad swathes of spectrum and even decode and store transmissions. People can setup their own DIY listening posts this way. For someone with the right setup and looking at the right time they would notice you are using an encrypted transmission. To figure out where you are would involve repeated detections from multiple points. An adjacent topic is pirate radio stations. The Youtube channel Ringway Manchester has a series of videos about historical UK pirate stations and their stories. You might find it interesting.
  - reaperman 3y ago
    I think you maybe answered a different question than what I intended to ask. I meant to ask - if I only transmit encrypted communications while I’m legitimately transmitting legal content … how would anyone differentiate illegal high-entropy encryption from legal high-entropy noise? Obviously anyone can track my transmissions with “fox-hunting”. But my transmissions would superficially be valid and legal. How would they notice the well-encrypted communications which theoretically should look like random noise?
    - dgacmu 3y ago
      To put this in different words, you're basically asking about steganography applied to a radio transmission. I think the answer is: unlikely to be noticed unless you were receiving particular attention for some reason. Though your noise might inadvertently violate bandwidth constraints. If you search for radio steganography or acoustic steganography you'll find a bunch of papers on the topic.
    - creeble 3y ago
      If it is above the S/N ratio, it won’t look like noise. If it is below, it’s hard to make useful.
    - thereddaikon 3y ago
      Ah, so if you are using encryption on a digital mode like DMR or P25 for example, they have very distinct sound and appearance over the air. Its pretty unmistakable as common digital modes can be identified by ear by experienced Hams. So if I am listening on my SDR and pickup a digital transmission on a ham band I can try to identify and decode it. If I am confident I've correctly identified the mode being used and I can't decode it then its probably encrypted. Some modes like DMR even carry some information unencrypted when the transmission is. So its still possible for someone without the key to correctly identify the transmission even if they can't hear what's been said. Trying to hide a transmission as background noise would be very difficult. I wouldn't say impossible but it wouldn't be easy. The modern technique is low probability of intercept, LPI. Which uses a combination of techniques including very rapid and complex frequency hopping as well as well as beam forming and making the transmission as efficient as possible to limit the required power. The lower power, and more more directional your transmission, the less likely someone unwanted will be able to pick it up unless they are between you and the intended recipient.
avidiax 3y ago
I think there's one more intrinsic safeguard for these radios vs. drones. Handheld radios are mostly not useful in an urban setting (compared with a cell phone), and only other radio users can even be bothered by them. Unlike "drone spotted in posh neighborhood looking into windows" as a headline, "Baofeng user briefly interferes with garage door opener" just doesn't have any edge.
- thereddaikon 3y ago
  That's a fair point but I've seen for a few years now Baofeng Ham radios resold as walkie talkies for recreational use. Often advertised as for powersports like ATVs and boating. This is completely illegal but these resellers have been doing it for awhile now without any consequences. Still, the real world impact is limited and mostly contained to annoying Hams. And its a meme in the community that the FCC doesn't care about Hams. I think the flipper zero/hack rf side of things is the bigger problem. Its very useful to whitehats but they also lower the bar for a lot of disruptive attacks. Get a flipper zero and war drive any neighborhood built in the 80's and its prime hunting ground for forcing garage doors. I'm surprised we haven't heard more of that actually.
  - ganzuul 3y ago
    > I'm surprised we haven't heard more of that actually. It’s a bit of an information hazard. E.g. what if someone made sewer pumps run backwards. Meanwhile the level of exploit capabilities is on the level of Spectre. There is such a wide gulf between what is and what should be that we can’t properly discuss it.
crmd 3y ago
Question from a non-ham: how does the fcc define encryption? Is it ok to speak in code, like a numbers station? What about speaking in Navajo, like the Americans did in ww2? What if it was a made-up tonal language with lots of clicks that sounded similar to a modem transmitting a bitstream?
- threeio 3y ago
  "messages encoded for the purpose of obscuring their meaning" https://www.ecfr.gov/current/title-47/part-97#p-97.113(a)(4) https://www.ecfr.gov/current/title-47/part-97#p-97.113(a)(4) It's intentionally broad, and gives exceptions for controlling satellites as the only real exception. People try to fight that publishing encryption keys would mean that you are within the intent of the law, I struggled decades ago trying to create a digital voice mode while every OM told me I was trying to encrypt things. sigh.
  - crmd 3y ago
    Awesome, thanks
- deleted 3y ago
  [deleted]
- thereddaikon 3y ago
  What threeio said is right. Technically, encoding data digitally isn't encryption and is fine, and there are digital modes used by Hams. But if you were to come up with your own scheme I could see some sweaty old timers try to accuse you of encryption just because their $3k Yaesu can't decode it. There's a good reason why a lot of recent innovation in the hacker and maker spaces has been in unlicensed bands. The rules for the Ham bands were written decades ago when just trying to talk to people around the world was considered experimental. Now its trivial to do that with HF with the right equipment and a bit of reading. The FCC tends to neglect the ham space which is both a good and bad thing. Lack of attention means people are probably getting away with doing a lot of harmless things they technically shouldn't be. But it also means we are stuck with rules from the 1930's.
fullspectrumdev 3y ago
> Imagine something as capable as a HackRF but as easy to use as an iPhone. This is literally just a UX overhaul away for the HackRF Portapak system. As-is the UX is slightly too awkward for the casual user, but these things trend towards becoming more user friendly over time. Honestly a Portapak with Bluetooth module and a phone app to control it would be pretty fucking cool, now that I think about it.
- brewtide 3y ago
  https://github.com/htotoo/ESP32-Portapack https://github.com/htotoo/ESP32-Portapack Looks like this may be in the works!
doubleg72 3y ago
You mean like the portapack, which is based on a HackRF and allows transmission on a broad range of frequencies.. https://github.com/portapack-mayhem/mayhem-firmware https://github.com/portapack-mayhem/mayhem-firmware At least the normal layperson would need to understand RF to cause any damage.

reaperman 3y ago

Assuming there was aggressive enforcement against it, could someone “get away” with encrypted transmission sent in low-power alongside high-power unencrypted transmissions? Like would a well-encrypted stream look indistinguishable to a bit of noise from a low-quality transceiver?

thereddaikon 3y ago
That depends entirely on what they are listening with. One sub set of ham radio is called fox hunting which is a gameified form of radio direction finding. Some guys are really good at it. If you annoy one of them and they are persistent they can potentially track you down. The Feds of course have very sophisticated tools far and above what's available to you but if you've drawn that kind of attention you are already in deep trouble and looking at jail time. Powerful software defined radios like the RTL-SDR are inexpensive and with a PC can be used to scan broad swathes of spectrum and even decode and store transmissions. People can setup their own DIY listening posts this way. For someone with the right setup and looking at the right time they would notice you are using an encrypted transmission. To figure out where you are would involve repeated detections from multiple points. An adjacent topic is pirate radio stations. The Youtube channel Ringway Manchester has a series of videos about historical UK pirate stations and their stories. You might find it interesting.
- reaperman 3y ago
  I think you maybe answered a different question than what I intended to ask. I meant to ask - if I only transmit encrypted communications while I’m legitimately transmitting legal content … how would anyone differentiate illegal high-entropy encryption from legal high-entropy noise? Obviously anyone can track my transmissions with “fox-hunting”. But my transmissions would superficially be valid and legal. How would they notice the well-encrypted communications which theoretically should look like random noise?
  - dgacmu 3y ago
    To put this in different words, you're basically asking about steganography applied to a radio transmission. I think the answer is: unlikely to be noticed unless you were receiving particular attention for some reason. Though your noise might inadvertently violate bandwidth constraints. If you search for radio steganography or acoustic steganography you'll find a bunch of papers on the topic.
  - creeble 3y ago
    If it is above the S/N ratio, it won’t look like noise. If it is below, it’s hard to make useful.
  - thereddaikon 3y ago
    Ah, so if you are using encryption on a digital mode like DMR or P25 for example, they have very distinct sound and appearance over the air. Its pretty unmistakable as common digital modes can be identified by ear by experienced Hams. So if I am listening on my SDR and pickup a digital transmission on a ham band I can try to identify and decode it. If I am confident I've correctly identified the mode being used and I can't decode it then its probably encrypted. Some modes like DMR even carry some information unencrypted when the transmission is. So its still possible for someone without the key to correctly identify the transmission even if they can't hear what's been said. Trying to hide a transmission as background noise would be very difficult. I wouldn't say impossible but it wouldn't be easy. The modern technique is low probability of intercept, LPI. Which uses a combination of techniques including very rapid and complex frequency hopping as well as well as beam forming and making the transmission as efficient as possible to limit the required power. The lower power, and more more directional your transmission, the less likely someone unwanted will be able to pick it up unless they are between you and the intended recipient.

avidiax 3y ago

I think there's one more intrinsic safeguard for these radios vs. drones. Handheld radios are mostly not useful in an urban setting (compared with a cell phone), and only other radio users can even be bothered by them. Unlike "drone spotted in posh neighborhood looking into windows" as a headline, "Baofeng user briefly interferes with garage door opener" just doesn't have any edge.

thereddaikon 3y ago
That's a fair point but I've seen for a few years now Baofeng Ham radios resold as walkie talkies for recreational use. Often advertised as for powersports like ATVs and boating. This is completely illegal but these resellers have been doing it for awhile now without any consequences. Still, the real world impact is limited and mostly contained to annoying Hams. And its a meme in the community that the FCC doesn't care about Hams. I think the flipper zero/hack rf side of things is the bigger problem. Its very useful to whitehats but they also lower the bar for a lot of disruptive attacks. Get a flipper zero and war drive any neighborhood built in the 80's and its prime hunting ground for forcing garage doors. I'm surprised we haven't heard more of that actually.
- ganzuul 3y ago
  > I'm surprised we haven't heard more of that actually. It’s a bit of an information hazard. E.g. what if someone made sewer pumps run backwards. Meanwhile the level of exploit capabilities is on the level of Spectre. There is such a wide gulf between what is and what should be that we can’t properly discuss it.

crmd 3y ago

Question from a non-ham: how does the fcc define encryption? Is it ok to speak in code, like a numbers station? What about speaking in Navajo, like the Americans did in ww2? What if it was a made-up tonal language with lots of clicks that sounded similar to a modem transmitting a bitstream?

threeio 3y ago
"messages encoded for the purpose of obscuring their meaning" https://www.ecfr.gov/current/title-47/part-97#p-97.113(a)(4) https://www.ecfr.gov/current/title-47/part-97#p-97.113(a)(4) It's intentionally broad, and gives exceptions for controlling satellites as the only real exception. People try to fight that publishing encryption keys would mean that you are within the intent of the law, I struggled decades ago trying to create a digital voice mode while every OM told me I was trying to encrypt things. sigh.
- crmd 3y ago
  Awesome, thanks
deleted 3y ago
[deleted]
thereddaikon 3y ago
What threeio said is right. Technically, encoding data digitally isn't encryption and is fine, and there are digital modes used by Hams. But if you were to come up with your own scheme I could see some sweaty old timers try to accuse you of encryption just because their $3k Yaesu can't decode it. There's a good reason why a lot of recent innovation in the hacker and maker spaces has been in unlicensed bands. The rules for the Ham bands were written decades ago when just trying to talk to people around the world was considered experimental. Now its trivial to do that with HF with the right equipment and a bit of reading. The FCC tends to neglect the ham space which is both a good and bad thing. Lack of attention means people are probably getting away with doing a lot of harmless things they technically shouldn't be. But it also means we are stuck with rules from the 1930's.

fullspectrumdev 3y ago

> Imagine something as capable as a HackRF but as easy to use as an iPhone. This is literally just a UX overhaul away for the HackRF Portapak system. As-is the UX is slightly too awkward for the casual user, but these things trend towards becoming more user friendly over time. Honestly a Portapak with Bluetooth module and a phone app to control it would be pretty fucking cool, now that I think about it.

brewtide 3y ago
https://github.com/htotoo/ESP32-Portapack https://github.com/htotoo/ESP32-Portapack Looks like this may be in the works!

doubleg72 3y ago

You mean like the portapack, which is based on a HackRF and allows transmission on a broad range of frequencies.. https://github.com/portapack-mayhem/mayhem-firmware https://github.com/portapack-mayhem/mayhem-firmware At least the normal layperson would need to understand RF to cause any damage.