Open source 5G core network

by polymorph1sm • 6 years ago

168 48 6 years ago

So will this let me run a 5G baseband? I've read about Osmocom but I've never tried it out.

oddeyed• 6 years ago

Not quite, this is the "core network" which handles things like handset authz/authn, billing, base station attachement etc.

A 5G basestation is called a gNB, and a handset is called a UE. This project doesn't involve the radio interface of 5G, so neither of those are included. There's another comment on the post outlining how you might go about standing up an actual network using this.

Jhsto5• 6 years ago

For those interested, this project seems to be a rewrite of https://nextepc.org/ into Go. Alternative projects include https://github.com/facebookincubator/magma and https://github.com/openairinterface.

You can start your own telenetwork with these projects (but of course doing such would be highly illegal without a spectrum license), but first, you need a gNB or eNodeB which is lingo for a base station. It is possible to buy an SDR and use software like https://github.com/srsLTE/srsLTE to make the SDR receive and broadcast LTE/5G connections. After this, you need to have blank SIM cards to code. For example, this post instructs how to do so: https://cyberloginit.com/2018/05/03/build-a-lte-network-with.... You might also consider writing eSIMs https://github.com/bagyenda/njiwa.

After this, you should be able to use a commercial phone to connect to the network.

In general, these networks function quite well even on commodity hardware. Some tests I worked on produced end-to-end latency of around 20ms on LTE, and throughput of around 7MB/s. This was using NextEPC on a 400 euro computer with a 50 euro router and a Nokia base station. Further, it was possible to make the system to work in a Heroku like manner by exposing PaaS endpoints and running Kubernetes in the access network: https://www.semanticscholar.org/paper/Open-source-RANs-in-Pr...

I think it's quite likely that sooner or later we will have 5G networks with intra-services running as edge-services, providing us low-latency. It's worth noting that with the latest LTE versions 5G and LTE access latency is virtually the same. The real latency-optimization would be, at least to my perspective, to allow software to be deployed _into_ these cellular networks to minimize network hops.

newhouseb• 6 years ago

I'm not an expert, but there are variants of LTE and 5G (LTE-U and 5G NR-U) that support operating in the unlicensed 5Ghz band.

That said, I'm not sure a commercial handset would connect to anything in that range. You could probably get an SDR-based UE (UE is telecom-speak for "thing that connects to a cell network") to work.

Jhsto5• 6 years ago

Yeah, I'm not an expert either, but there are initiatives to this as well. One such initiative is Nokia Kuha: https://www.kuha.io/

The problem is exactly what you described: there are currently no commercial UE or base stations. So yeah, I suppose one is supposed to use SDR for the 5Ghz band.

bluishscreen• 6 years ago

https://translate.google.com/translate?sl=auto&tl=en&u=https...

Apparently, there are overlaps between common LTE bands and both ham radio bands and unlicensed (... low-power) ones... the above page states that any device with the right bands will work (... and they even got them working presumably?)

g_p9• 6 years ago

SDR-based UEs work for 4G right now (see srsLTE with the srsUE), but I'm not aware of an open source one that supports 5G standards yet.

There are unlicensed variants of LTE/5G, but worth noting that these often are designed to use the unlicensed spectrum as supplemental downlink (i.e. License Assisted Access (LAA) in LTE), rather than actually allowing for uplink and downlink in the unlicensed spectrum.

The reason for that is simple politics - mobile operators are powerful lobbyists, and part of a powerful standards group (GSMA), and don't really fancy the idea you should be able to run what a customer will perceive as a mobile network without significant investment in spectrum (a finite resource).

LTE-U and LAA won't let you run a network by yourself just on unlicensed spectrum. Multefire should, but is quite rare for the obvious political reasons outlined above.

numpad0• 6 years ago

You mean sXGP?

jcrawfordor• 6 years ago

LTE-U is commercially available and currently in use on a limited scale for wireless internet service. The main (and almost only) manufacturer of base stations and clients is a company called Baicells.

While LTE-U does have some advantages over WiFi for WISP use (e.g. better handling of a large number of clients per AP), the higher cost (around ~$9k for an LTE-U eNodeB compared to as low as $500 for a WISP-grade 5GHz WiFi AP) and scarcity of vendors means that it's not very commonly used. We'll see if that changes over time, but WiFi has a huge amount of inertia in that space so it seems difficult for LTE-U to catch up considering that the power levels are limited to such an extent that it doesn't have a huge range advantage over WiFi with good antennas.

In fact, just looking at Baicells it seems that they offer fewer models for LTE-U than they used to, so they may be finding that sales aren't enough to keep up the product line.

solarkraft• 6 years ago

I think it's quite likely that sooner or later we will have 5G networks with intra-services running as edge-services, providing us low-latency.

Noob question, sorry, but: Why not Wifi?

Jhsto5• 6 years ago

LTE (and 5G on 3.6Ghz, I guess) signal can cover many kilometers. The protocols are built to be more reliable (a phone keeps a tab of access points to which it can quickly hop if access to one base station is lost) and the licensing ensures that there cannot be spectrum suffocation at any time, which is quite common in bigger cities with WiFi.

14k12j41j2114• 6 years ago

Mobile networks allow seamless switching of cells. If you're on a call while in the car, your connections won't drop and ideally you wouldn't loose a single packet.

Network and smartphone monitor nearby cells. If you're just about to switch the cell because the quality becomes too bad, everything is already being prepared in the next cell.

ksec3• 6 years ago

Because 5G, or even 4G LTE is still technically superior to even latest WiFi 802.11ax.

non-entity3• 6 years ago

Any recommended resources for learning about mobile communications technologies that aren't overpriced engineering certificates or surface level marketing material for / from telcoms?

Jhsto5• 6 years ago

Coming from a software background, I think NextEPC and its new variant called Open5GS have the most down-to-earth documentation and code to start from: https://open5gs.org/open5gs/docs/. The authors have many good papers that are easy to follow. Osmocom also has good resources https://osmocom.org/projects/cellular-infrastructure/wiki

Most of the learning curve comes from the lingo. Especially now that 5G introduces softwarization of many of the network functions, the terms used by the cellular and software industries clash and may be confusing at times. But you can definitely learn the high-level idea of how the cellular networks function in this way.

For physical level things, I imagine that a degree in signal processing is required. And for more advanced software interfaces, I am afraid that you can only read about them, as most devices on which the software is implemented is proprietary. The open-source software you can find is in no-way as fully implemented as the actual software which runs commercial networks.

14k12j41j2114• 6 years ago

https://www.sharetechnote.com/

g_p9• 6 years ago

Just to add to the above, some countries have very lightweight spectrum access and licensing regimes. Ofcom in the UK let you apply for a low power license (fine for around the home etc.) for a relatively nominal fee, and that will get you usable mobile spectrum - 3.3 MHz in the DECT guardband at the top end of the 1800 MHz band (FDD Band 3), or the 10 MHz slice at the top of the 2300 MHz band (2390 to 2400 MHz, which is TDD band 40).

From memory, a 1-year local spectrum license should cost about £50.

mcspiff• 6 years ago

That’s basically what AWS has proposed with Wavelength: https://aws.amazon.com/wavelength/

matt9j2• 6 years ago

Magma at its initiation extended a hard fork of OAI. The projects have since diverged quite a bit, but some of the core bits are still shared. NextEPC was renamed to open5gs a while back, and a lot of the open source telecom work seems to be happening there https://github.com/open5gs/open5gs . The project was recently reorganized by its founder though, and currently requires a CLA to contribute upstream.

rob-olmos• 6 years ago

Somewhat related recent curiosity: Is there anything new about 5G tower/backhaul infrastructure for edge computing that wasn't already feasible for 4G?

g_p9• 6 years ago

Nothing hugely different to "late stage 4G" (Release 14). The main difference with 5G (that was available in Rel14 but not widely used by anyone) is control and user plane separation, which means some network traffic can leave the user plane at the base station, and go elsewhere, rather than be routed all the way back to the core network.

That enables edge computing by allowing traffic for the edge computing node to be routed to the local edge node directly, without it going down the backhaul.

This is very much a software change though in the implementation of the base station.

foobiekr2• 6 years ago

exactly, control-userplane separation is the primary differentiator for "5g." the whole point is to eliminate backhaul and allow closer CDNs and caches..

chvid• 6 years ago

Is this really what constitutes a "5G core network"? Does it mean that I can buy Huawei for the rest of it and set it up in the UK?

g_p9• 6 years ago

This is a few components that make up the very baseline of some aspects of a standalone 5G core.

If you want to add commercial base stations to it, you'll find you're missing a few non-standardised things missing from all "open source" solutions - you'd need base station orchestration and control, to handle configuring and managing the base stations and getting them to behave in the ways you want.

For one or two base stations you might cope without it, if you can figure out how to configure the radios, and they happen to work. But generally, there's a load of integration to be done that isn't part of the standards, and that you'll need in addition to this. You'll also need to handle scaling up and clustering some of the components that need to scale up with traffic.

ComodoHacker• 6 years ago

Can't find where COVID-19 infection code is. Is it not implemented yet?

14k12j41j2114• 6 years ago

Let's hope nobody finds out about Presidential Alerts. Basically, it lets you send Tweets to any mobile user.

g_p9• 6 years ago

Fairly straightforward to use these in other core networks. Not sure if this one implements the signalling for it.

Fun fact though - if a phone is without signal on its home network, it will attempt to join any valid 3GPP network it sees, and the cell broadcast/emergency alert will be triggered on the handset (even without a valid SIM) - no authentication takes place.

tpmx• 6 years ago

This won't have a chance to win unless e.g. Cisco/Google/Apple/FB somehow decides to fund a few thousand developers each yearly. And they won't do that unless there's clear incentive for them.

In a way I really hope they won't. How could anything good come out of that?

From an engineering perspective: the software stack is conceptually (if you squint enough) a bit like webkit/chromium, but on top of that you also need cutting edge radio/antenna development.

Open source 5G core network

Related Stories