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Free and open source solutions now exist for every component that is required to create a 4G cellular (LTE) network, all the way from the radio access network (RAN) and core, to services which are used for integrated voice (VoLTE). Creating a fully functional mobile network is the next logical step, but this requires overcoming the final remaining technical hurdles. This project will provide end-to-end integration of a FOSS technology stack for 4G networks, via a validated hardware and software configuration that is subjected to appropriate testing. Together with additional tooling and documentation for repeatable deployment, the project will making it far easier to create a self-contained 4G network than ever before. This is particularly timely given the availability of low cost software-defined radio (SDR) hardware, coupled with the efforts of wireless regulators to provide increased access to spectrum for private and community LTE networks.

Why does this actually matter to end users?

For many people, especially those living in urban areas, mobile internet and mobile telephony literally just fall out of the sky. It's there, invisibly. But of course, wireless communication is not really wireless: somewhere near, often discretely hidden, there is a powerful antenna on top of some specialised radio equipment. On one end that equipment establishes a radio link with our phone or tablet through electromagnetic waves, and on the other end it connects to the internet and the telephony network - through a fiber optic link or a copper cable.

After that explanation, we might think we understand a bit more how wireless communication works. But we run into new unknowns: how does that equipment actually work? Can we really trust it? How can we tell? Meanwhile, we heard enough warnings about the possibility of mobile network equipment being backdoored, and used to spy on people. And who decides which equipment is put where, what it costs to get access to the network and how our communication is protected? Now compare that to how you use your wifi at home: you also connect to a device over a radio link, but you control that device yourself. You can change the security settings yourself, add any device you want without having to ask for permission, and even take the whole device apart to see what it does. Wifi gives a lot more ownership.

If you consider how much wifi and mobile telephony resemble each other at a technical level, how odd is it that one technology is so close within our reach - and the other is really almost a black box? If someone would tell you that downloading a video your mom posted online would cost you 5 euro to download on your home wifi, you'd politely tell them to go away. If someone told you that they were very sorry but that your wifi is always going to be crappy because you live in a pocket of the network, you'd pick it up and put it somewhere else; or add another antenna, or change the equipment altogether. And if someone told you they would use your wifi signal strenght to inform some third party whenever you move from one room to the other, you'd be more than right to be angry. So why can't mobile telephony be more like wifi?

This project is about building an open hardware mobile telephony and data network. It allows anyone - of course within the bounds of the applicable legislation - to learn about and experiment with mobile telephony. The goal is to produce a fully functional 4G network, with everything you would need to actually use it as a daily driver - and a lot of documentation to help you on your way. Everything can be inspected and modified from top to bottom. That way, you can make sure your own telecom network is fully trustworthy and private.

Run by AB Open Ltd

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This project was funded through the NGI0 PET Fund, a fund established by NLnet with financial support from the European Commission's Next Generation Internet programme, under the aegis of DG Communications Networks, Content and Technology under grant agreement No 825310.

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Please check out NLnet's theme funds, such as NGI Assure, NGI0 Discovery (which is focussed on search, discovery and discoverability) and the Internet Hardening Fund.

Want to help but no money to spend? Help us by protecting open source and its users.