Oh! Happy to see Listen to the cloud posted here! It’s been a crazy ride since I built it last November. I went viral in Russia and Kazakhstan And were interviewed by a Spanish newspaper called El Mundo together with Eric (who made youarelisteningto). The best outcome of it was receiving an email from a developer who had a lot of problem with ADD and anxiety and he told me about how listentotheclouds helped him focus while at work and expressing the gratitude. It’s very humbling to hear that something you built just for fun actually helps others in ways you had no idea it would.
Thank you, this is really nice!
Tho, one question: Why does the ISS Space Station channel ask me to install Flash, while all the other channels seem to work just fine?
(And another also - the original Grand Theft Auto had a CD audio track that represented the ambient police audio; that's what played when you were in a police car, ambulance or fire truck. There's also a City Ambient for when you're walking around. ( https://www.youtube.com/watch?v=87Ls5ImYEXA )
P25 is very vulnerable to jamming, decrypting encrypted traffic, traffic analysis, and geo tracking of individual radios.
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Because of the design of P25, commonly used in America, if you enable encryption, a tiny bit of noise in the signal makes it unusable. One problem is that there are separate error correction codes for different parts of the packet, and very few error correction bits were allocated for the important encryption bits.
To get around this, sometimes just the dispatchers will have encryption on, since those packets are traveling over fiber to the transmission towers, where they are broadcast at high power levels. The other direction, personal radio to repeater tower, is almost never encrypted because of the much lower power of the personal radios.
P25 has some nice features - our local area has perhaps a hundred different public safety organizations, all of which can talk to each other at any time, and often coordinate for any major incident. But security is not one of them.
"P25 has some nice features ... but security is not one of them."
And that is just fine.
Police and firefighters/medics[1] are civilians and are in their role to serve civilians at the pleasure of civilians. There is no need for secret comms and, in fact, it is often quite valuable for the public at large to have visibility into their operations in real time.
There is no need to encrypt public safety radio comms and you should be quite suspicious of anyone who claims that there is.
Those radios belong to you. The frequencies belong to you. The people who use them are your own servants.
Agree, it is probably good for police / fire / EMT etc. to be open.
However, the linked talk above notes that the researchers accidentally discovered that some "sensitive tactical law enforcement operations" were unwittingly operating in cleartext, and divulged to the open air "names and/or identifying features of targets and confidential informants, their locations, descriptions of undercover agents, [...] plans for forthcoming takedowns and operations," and a few other things you probably don't want to widely announce.
It also notes that radio locations could be easily discovered, even if they're not communicating. Bad guys could therefore build a map of possibly-federal-agents in the city, and learn things they're not supposed to know even if they can't hear what's being discussed.
Again, PD/Fire/EMT are great to have open and mutually communicating. But there are (life and death) reasons why you might really need a secure channel in other cases.
>However, the linked talk above notes that the researchers accidentally discovered that some "sensitive tactical law enforcement operations" were unwittingly operating in cleartext, and divulged to the open air "names and/or identifying features of targets and confidential informants, their locations, descriptions of undercover agents, [...] plans for forthcoming takedowns and operations," and a few other things you probably don't want to widely announce.
We expect block headed 18yo infantrymen not to send sensitive information over insecure channels. I don't think asking the same from our public servants is unreasonable.
AFAIK in Europe they have full-encryption. But the presence of encrypted traffic in the reserved airwaves near you means there are cops/fire/ambulance nearby. I remember reading about someone building a cop radar by exploiting this property!
There are false positives (e.g. you're speeding down the autobahn, and there's an ambulance in a town you're passing through), but it's probably good enough...
Because of the design of P25, commonly used in America, if you enable encryption, a tiny bit of noise in the signal makes it unusable.
That is incorrect. There is no difference in voice quality or degradation in quality of service between an encrypted P25 signal and an unencrypted one.
An analogy would be like claiming that there is a difference in quality of service between http and https.
There's no voice quality difference, if the packet goes through, that's true.
The problem is that without encryption, P25 packets can handle a bit of radio noise and still be error corrected into usability. With encryption, in practice, certain bits get altered that cannot be error corrected and the packet cannot be decoded. P25 error correction ability is not evenly across the entire packet.
HTTP and HTTPS are riding on top of TCP, which mostly guarantees in order bytes, the correct bytes, and no missing bytes. If you loose the guarantees of TCP, and allow say 1 out of 2000 bytes to be altered randomly, HTTP would still mostly work, and HTTPS would be dead as a doornail.
Again, that is incorrect. Error correction is applied after encryption via 2.8kbs /sec of forward error correction paired with 2.4kbs /sec of data signaling. And the IMBE vocoder also provides it's own error correction.
The signaling, voice and error correction is then formatted into P25 speech frames. A transmission starts with a header data unit, identifying the destination of the call and if encryption was used or not.
It then continues with a series of logical link data units (LDUs), that carry the digital speech. The LDUs also repeat the signaling information and the synchronization sequence, so radios can join the call late, or reenter if they drop out due to bad RF coverage and then come back into the call. The call ends with a terminator data unit, indicating that the PTT’s been released, and this is the end of the call.
To get around this, sometimes just the dispatchers will have encryption on, since those packets are traveling over fiber to the transmission towers, where they are broadcast at high power levels. The other direction, personal radio to repeater tower, is almost never encrypted because of the much lower power of the personal radios.
This is also not correct. Encryption can either be manually turned on or off by the individual user (radio) and/or the dispatcher, or encryption can be "strapped" to a talkgroup in cases where full time encryption is used. THe scenario you describe is all based on the user's choice, not an operational need due to power levels.
"Because of the above-described property of the error
correction mechanisms used, especially in voice frames
such as the LDU1 and LDU2 frame types, there is no
mechanism to detect errors in certain portions of transmitted
frames. This was a deliberate design choice, to
permit undetected corruption of portions of the frame
that are less important for intelligibility."
Can someone explain to me why police scanners are so popular? I recently came across some guy (https://www.reddit.com/user/regoapps) who made millions off of making a police scanner app. Is the demand really that high? What's the appeal?
Edit: Why am I being downvoted? It's a genuine question... I see listening to police scanners is a popular thing and I just want to understand why
I think the downvotes might be because it seems you haven't explored possible motivations on your own and it comes off as dismissive. While it may not be appealing to you, it pays to spend a bit of time thinking about what might be appealing to others. That's not to say you haven't done this; sharing what you had thought about may have staved off downvotes.
Okay I understand. I see from this thread and a thread from a couple of years ago that some people are using this as a background noise. I tried doing this but it's too sporadic and the talking is distracting for me to focus on programming. It also makes me feel a little anxious for some reason.
I didn't mean to offend anyone's interest, I just wanted someone to maybe show me a side I'm not seeing. I should word my questions with more thought and empathy in the future.
J-F, I would generally ignore the downvoters. Because you have to 'read the tea leaves' to try to know why somebody downvoted you, and you can only 'make stuff up' as to the potential reason. THAT means there is no objective feedback mechanism to learn how to avoid downvoting; or, in particular, why your specific contribution was downvoted.
In my world, posting a well-reasoned on-target opinion on a website is not isomorphic with a video game, where I need to score XP or some other adolescent incentive.
So, given the lack of specific feedback, I suggest you ignore the downvoters, and do what I do, which is to imagine them as ignorant youngsters who actually think anybody cares what they think. They lack power in their own lives, and so they get the illusion of power over others with their downvote button. We should feel sorry for such creatures.
My parents listen to a small county's sheriff dispatch on Broadcastify when my brother is working his shift. I sometimes listen, too. It's mostly mundane stuff, and lots of domestic disputes, making it seem odd that hundreds are listening to a small town's dispatch. But sporadically you'll hear something interesting (e.g., needing backup to help apprehend a 300lbs guy who's huffing propane), which I guess explains it. Or, there are simply that many family members listening.
As an amateur radio geek, the first thing that stood out in my home state was the apparent massive disparity between LA and SF police radio traffic. SF appears to still be analog, and still uses "10-4" as a code??
Considering all of the lack of public trust of police departments these days, I'd prefer that they don't use encryption. But, I'm sure there is more than one side to the issue.
They have the gear but few implement encryption. Most police departments are more worried about not beimg heard than of bad guys listening in. Normally only drug squads use encryption.
Are US police radio still broadcasting unencrypted on public frequencies ? I know for a fact eavesdropping is forbidden in some european countries and the broadcasts are encrypted in some.
Yes, with some exceptions. We lean much more heavily towards open/public records and “sunshine is the best disinfectant” than privacy. The ability of an independent press to observe and audit police activity is considered by many (myself included) to be foundational to liberal democracy.
Unless they're broadcasting "just planting some drugs on this suspect, over", having the transmissions unencrypted probably isn't a very useful way of auditing police activity.
On the contrary, there have been several high profile incidents where police radio traffic was used to demonstrate ill intent. It's difficult to use a tool day in, day out like that without getting complacent.
Open radio also makes it more likely the news media is there when the action is still happening instead of giving cops time to paper over their mistakes.
The point is that deployment of police power to a particular location/situation becomes public record immediately and unconditionally, and the press can (and does) follow up on it.
Police getting to operate in secret is a dangerous road to go down. Same reason that the names of suspects who get arrested are public. It might suck for their future reputations, but the alternative is a world where the police get to make people disappear.
Just as an interesting anecdote about laws regarding listening to police radio. In New Zealand, it's not illegal to listen to police radio (although a lot of it is not digital and encrypted), however, it is illegal to act on information gained from listening to it. I don't know exactly how this works in regards to journalists using police scanners, but I've never heard of anyone getting prosecuted for that sort of thing.
Did anyone else immediately think that should read “you are listening to Los Angeles” because of the Soul Coughing song? Nice to see that it’s an option on the site.
I revisited that thread, and upvoted a few comments from almost four years ago. Good luck figuring out which comment got the upvote when your points count goes up. :-)
Worth noting, though, are the SomaFM links to similar stuff over there. I’m a big fan of Mission Control myself.
Is there anyway to turn of the music or switch channels? Ambient music is not my cup of tea, I'd rather just have the scanner play without Yanni in the background.
Listen to live Bitcoin transactions: http://btclisten.com/
Listen to airports: http://listentothe.cloud/
Listen to train ride: https://www.youtube.com/watch?v=9pVWfzsgLoQ
Listen to driving through NY: https://www.youtube.com/watch?v=3kV4zowtJC8