Can someone explain the use case for this project?
Is it intended for device vendors creating phones and tablets or for telecom companies building their own infrastructures?
Is it intended for device vendors creating phones and tablets or for telecom companies building their own infrastructures?
This project tries to build an open solution following O-RAN standards for RAN software. It is targeting telecom. companies for their Radio Access Network (RAN). Their infrastructure is divided into the Core Network (like a simple internet network) and the Radio Access Network (base stations, antennas and all that stuff). Phones and tablets are User Equipment (UE), nothing to do with srsRAN.
Genuine question.
It looks so closed and complex compared to more traditional comms like wifi or even ethernet.
You could build srsRAN and run a local eNodeB instance to form a local LTE network. Given that it has a radio that operates in the LTE bands, in theory you might be able to build srsRAN for a phone and run the necessary base station software (eNodeB and EPC) on a phone to form an "ad hoc" network. It wouldn't be truly ad hoc in that the network would still have a base station, just that it would be running on phone hardware. srsRAN wouldn't be running as an application, but would be replacing the firmware in the phone's LTE modem.
Edit:
Here is a paper by someone who has built an ad hoc LTE network.
https://arxiv.org/pdf/1802.09262
It does exactly the above: using srsRAN (which used to be called srsLTE) to run local base station software (eNodeB+EPC) to get around the asymmetry in the LTE protocol.
Because billing.
All the complexity in cellular can be traced back to making the system secure the whole way back to SIM cards because there is actual money at stake if the system gets cracked.
If you like, you can consider just plain old VOIP where the central entity is used for discovery but the actual call may then be routed p2p though not in VoLTE and its successors of course because the media plane is also centrally routed.
However, if I’m not mistaken 5G has V2V comms (Vehicle to Vehicle) specifically designed for self-driving cars, drones and IoT and that is the most “ad hoc” it can get
Networking between phones, without a common base station, is hard. Harder than WI-FI, because identity is managed centrally and the frecs in use require a license to name some "simple" problems. Cellular comms are not designed to handle this kind of scenario.
There has been some work to add inter device connectivity lately, to support many interesting use cases. You can find more looking for "sidelink" or "PC5", but you will not find many phones that implement it.
It seems to be mostly focused in vehicular use cases in V2V and V2X scenarios
5G also has a peer mode, and I'm trying to figure out if it can be implemented in userspace or has to be done in firmware.
My idea is that peer mode would be useful for replacing walkie-talkie or mesh messaging like Meshtastic since everyone has a phone. The range is supposed to be around a mile.
Proprietary, Closed Standards: no
Here are all the 3GPP 4G/5G standards that govern cellular phone networks:
https://www.3gpp.org/specifications-technologies
Also look under the "Specifications" drop down menu at the top of the page. Every release is listed.
These standards being freely available is why SRS were able to write srsRAN. There is nothing stopping others from doing so either, apart from the amount of information that has to be understood and digested.
Edit: Apart from complexity the other potential barrier is patents, but that's not a technical barrier.
Those technologies aren't terribly useful to use in your house like WiFi is, and even if they were, you need more government paperwork to do it. That means less hobbyist interest.
Use cases are partly captured by the list of customers across the bottom of the srsRAN home page (https://www.srsran.com/). It's great for any company/research group smaller than a multinational base station manufacturer, at which size the big players don't want to talk to you.
- Testing of various kinds. You can get deep inside an OSS base station, inspect and debug things, but likely may not even look at the proprietary innards of a commercial BS.
- Emergency connectivity when the backbone is broken, or did not exist. Most people would bring mobile phones anyway.
- Study / teaching, like MINIX OS or trainer aircraft which you can take apart and inspect.
- Maybe very small local cells to improve connectivity in difficult landscapes (mountains, skyscrapers, underground).
I was wondering a bit whether that means Base Station or perhaps something else...
Something like this would've been useful in a couple remote networks that I worked on. Internet was easy to get with some ubiquiti wifi routers and antennae. Getting cell reception was a pain in the ass that involved setting up a repeater in the one spot of the valley where reception was kinda okay. I haven't looked into the project too much, but I imagine I could set it up to connect to a telcom tower and handle the wireless backhaul similarly to how I did the wifi.
Edit: An open implementation like this could lead to cheaper cells for large, concrete/metal buildings that typically have terrible reception.