Receiving Opensky with Brand Equipment

[kb1ipd]

I recently noticed that there were some opensky basestation units that showed up on eBay. As it turns out, this stuff shows up on eBay and similar auction sites from time to time and is not always that expensive.

Since Opensky remains the one elusive format that nobody can seem to decode, I'm just wondering if snagging some official equipment would allow that, for example using the "digital voice conversion" method, where an IF output is fed to a mixer and then to the input on a radio.

I would think it would really depend on whether Opensky is always encrypted and also whether or not it's possible to make the equipment receive all transmissions and not just those addressed to the talkgroup of the equipment.

Does anyone know if this works?

 

[n5ims]

You may want to monitor this thread (http://forums.radioreference.com/ha...36670-i-purchased-some-opensky-equipment.html) before you spend your money. That thread is from somebody that got some of the equipment and is trying to get it to work and finding out (at least at this point) that having the equipment isn't much help with OpenSky.

I dont believe these are programmed like a current radio. I believe its more like it log into the system when you turn it on and donwloads a profile of channels to the radio.

Frank

Without a valid login to the system even the equipment apparently isn't much help. I suspect that the login isn't something that a user enters, but something like the equipment's ESN (electronic serial number) that's hard-coded into the radios and if that radio isn't in the list of valid ones for that system, it's just some metal and components. Hopefully that thread will get an OpenSky guru to provide some useful info on making things work.

 

[kb1ipd]

hmmm.... So basically the equipment will only respond to the transmissions addressed to it? Is this because it's encrypted or just because it's not programmed to do so? if it's the later, there must be some way to decode the signal by dismantling the equipment and feeding the raw signal directly into the demodulator or something like that.

Also, I can't imagine Harris doesn't make some kind of service monitor or dispatch base station that can tune in all transmissions.

 

[rbouch]

the opensky system is IP driven. If your units IP address and S/N are not in the system you WILL NOT recieve the transmissions. The consoles and any test radio's have to be registered on the network. it is just how the system works. everytime you turn your radio it registers on the system and downloads the profile to the radio. there is some limited memory held in the radio but it really varifies the info before it grants you access to the system. it is just like logging into the computer network.

 

[kb1ipd]

the opensky system is IP driven. If your units IP address and S/N are not in the system you WILL NOT recieve the transmissions. The consoles and any test radio's have to be registered on the network. it is just how the system works. everytime you turn your radio it registers on the system and downloads the profile to the radio. there is some limited memory held in the radio but it really varifies the info before it grants you access to the system. it is just like logging into the computer network.

Yes, an in a computer network, if the traffic is not encrypted, you can use something called a "packet sniffer" to receive and decode traffic not addressed to you.

 

[K4NNW]

the opensky system is IP driven. If your units IP address and S/N are not in the system you WILL NOT recieve the transmissions. The consoles and any test radio's have to be registered on the network. it is just how the system works. everytime you turn your radio it registers on the system and downloads the profile to the radio. there is some limited memory held in the radio but it really varifies the info before it grants you access to the system. it is just like logging into the computer network.

While that information is quite appreciated, it still seems like Not-So-OpenSky has more points of failure than any other radio system known to man. Who thought that was a good idea (and for what reason)?

 

[W2GLD]

Opensky users are each required to login to their individual radios. Upon a VALID login, the radio queries the server and sends the AUTHORIZED, available channel access grant to the users radio. The user ONLY has access to those channels the system administrators have authorized. In addition, there IS a layer of AES encrption placed on top of the data stream.

Simply having Opensky equipment is of no use for monitoring these systems; unless you know someone who will add you as a user on their system; but that also has other legal ramifications for whomever does this as they'd be facilitating unauthorized use of county/state/federal networking and telecommunications systems.

Opensky is by far the MOST secure system around right now; thus why the military have gone or are in the process of moving all comms over to...

 

[kb1ipd]

Opensky users are each required to login to their individual radios. Upon a VALID login, the radio queries the server and sends the AUTHORIZED, available channel access grant to the users radio. The user ONLY has access to those channels the system administrators have authorized. In addition, there IS a layer of AES encrption placed on top of the data stream.

Simply having Opensky equipment is of no use for monitoring these systems; unless you know someone who will add you as a user on their system; but that also has other legal ramifications for whomever does this as they'd be facilitating unauthorized use of county/state/federal networking and telecommunications systems.

So you are saying that the system IS always encrypted? If it's not encrypted then it's perfectly legal to listen to, even if it uses a strange and proprietary encoding.

The question is whethe the voice packets are always encrypted. If they are, then it's a no go. If they're not, then it does not matter if the radio is programed to receive a given channel or not. If it's not encrypted then you might be able to grab the signal and pipe it into the radio's decoder circuitry. It's just "packet sniffing." You just make it blindly decode whatever voice stream is fed to it, but that's not going to work if it's actually encrypted.

Opensky is by far the MOST secure system around right now; thus why the military have gone or are in the process of moving all comms over to...

It's so secure even the people you want to talk to can't receive it half the time!

 

[W2GLD]

So you are saying that the system IS always encrypted? If it's not encrypted then it's perfectly legal to listen to, even if it uses a strange and proprietary encoding.

The question is whethe the voice packets are always encrypted. If they are, then it's a no go. If they're not, then it does not matter if the radio is programed to receive a given channel or not. If it's not encrypted then you might be able to grab the signal and pipe it into the radio's decoder circuitry. It's just "packet sniffing." You just make it blindly decode whatever voice stream is fed to it, but that's not going to work if it's actually encrypted.




It's so secure even the people you want to talk to can't receive it half the time!

While I am NOT a proponent of Opensky systems at all for general public-safety communications, I do understand the design architecture and why they've done some of the things they've done. It's a great data platform, it's robust, stabile, and secure; just ask FedEx, they've been using Opensky technology for sometime now.

The entire data stream is encrypted with varying levels of AES; depending upon what the individual contract and municipality requested in the original bid or subsequent modifications thereafter. As for government communications using Opensky; forget it... These guys are using specialized formats of encryption that are not available to the general public-safety market; especially those overseas countries like Iraq and Afghanistan... The systems aboard the naval vessels and various bases throughout the U.S. soil are also tightening up their encryption algorithms with the implementation of these new Opensky systems.

The voice paths are generally encrypted from site to site, mobile to mobile, portable to portable. Some agencies, like Oakland County, Michigan have taken this a step further and encrypted the traffic on their wired network backbone between the dispatch consoles and the remote stations. The encryption choices with this platform are becoming endless.

Again, Opensky in my opinion is much better for mobile data than anything else; even your comment about users not being able to hear each other is in-fact somewhat justified. Early on, when it was M/A-COM and they were trying to get their four talk paths per channel feature to work; there were MANY lost communications. Since Harris has taken over; Opensky has been overhauled and is now a fully functional four talk path secure digital trunking system that offers excellent voice and data options to various agencies...

Welcome to the 21st century of communications; yes it sucks, but remember, Harris isn't the only bad guy here, Motorola's new Project-25 Phase-II systems are being pushed by sales personnel to include 100% encrypted features for all users... There's allot of wasteful spending of Homeland Security money going on in government these days... Is there a need for some of these things, sure for tactical operations and surveillance, but do the trash trucks really need to have encryption? You're a taxpayer, you be the judge...

Anyway, good luck trying to decode Opensky; I'll be watching this thread with the utmost curiosity into your results.

 

[SCPD]

The Opensky systems in central Texas run 12.5 kHz wide channels supporting two slots for voice or data.

The version described by W2GLD is the older 25 kHz wide 4 slot format.

Yes, there are two versions of Opensky.

 

[AlexC]

Since this protocol already runs on IP... I can see them just switching the RF components out with LTE... plug and play and think of the voice capacity.....

 

[kb1ipd]

The entire data stream is encrypted with varying levels of AES; depending upon what the individual contract and municipality requested in the original bid or subsequent modifications thereafter.

If that is the case, and it's not standardized, but based on requests and whatever customizations are in the system, then it begs the question do all municipalities select full time encryption?

If there's a variance or it's somehow related to options, then that suggests there could be examples where that option is either not selected at all or not for all transmissions.

 

[Trinity-Explorations]

I still have my open sky equipment listed in the thread above, I purchased the equipment with the intention of using it for something.
It would of been nice to put together my own open sky system for voice and data, but the software is pretty much unattainable and i still am not clear what other equipment i would need to put a home brew system together. It would be nice to put my equipment to use. It's getting dusty

 

[HM1529]

System users on OpenSky do not have to login. On Pennsylvania's system, individual user login depends on the agency and how they had their radios set up. Some agencies do require an individual user profile with login every time the radio turns on. For other agencies, you just turn the radio on and go. The radio ID is stored in the main database in Harrisburg and gets its designated profile at boot up, Any user who has a system login can pick up any radio on the system and enter their login info to download their user profile to that radio. I'd have to go dig up the training materials, but I think that one user ID can be logged in to three radios.
Being an IP based system, though, you're still not going to get anything on a non-authorized radio even if login is not required.

As far as encryption, OpenSky certainly allows for top level systemwide encryption and a whole host of options down to the end user activating the encryption switch on their radio, but that encryption is not necessarily the standard on all systems.

Since when is OpenSky the new military standard all over the world? Yes, Harris is a long time defense contractor and the current owner of the OpenSky brand, but I've not seen anything indicating that OpenSky is used throughout the military. Could you point me toward any documentation? I'd like to read some more about military use of OpenSky.

 

[kb1ipd]

Being an IP based system, though, you're still not going to get anything on a non-authorized radio even if login is not required.

That should not necessarily matter. In an IP-based system, if you have the software correctly setup you can decode packets even if they are not addressed to you. It's called "Sniffing"

Imagine we have an open wifi network. You are sending packets to and from a router. I am on another computer. My computer ignores those packets because they are not addressed to me. But I can setup my software with something called a "packet sniffer" This tells the network card to listen to all packets, addressed to me or not. And I can use this to eavesdrop on your transmissions.

If the packets are not encrypted, then it should be possible to "sniff" them, although it might require a change in the firmware or something like that.