1. Shared access licence. There's 3.3 MHz (duplex paired) of former DECT guardband available for local use at the top of the 1800 MHz band. This should work fine to run 2G or 4G. There's 10 MHz of TDD at 2390 to 2400 MHz, indoor use only I believe, and most useful for 4G. There's also 3.8 to 4.2 GHz which allows outdoor use, and is dedicated shared spectrum for 5G. Transmit power limited aren't enough to run a big commercial network, but are enough to deploy a private network on a campus or private site.
The former two should be widely supported on handsets. The latter (5G option) is aligned with band N77.
2. If you're in a rural area, get a local access licence to "take" existing operator spectrum and use it legally, with 3 years max tenure. It can be renewed if the operator has no intention to use it. Operators don't like this, as they see spectrum as their owned property, but this isn't the case, and they only have a right to use it...
The process of getting a local access licence is deliberately complicated by operators as they don't want you doing it, but it can be done. You need to understand the technology and commercials of the industry though to realistically be successful. Some operators want you to talk to them first, others want you to talk to Ofcom first. If you know what you're doing, and make a strategically selected request for spectrum, it can be done. You can operate a commercial service in this spectrum, but you have to be clear to users the time-limited nature of spectrum access.
Going forward though, it's clear from Ofcom's own priorities that a more dynamic nature of spectrum allocation and utilisation authorisation is a priority and likely to be coming down the line - it's been a work item the last couple of years. Once that comes, we could see easier ways to access spectrum. Realistically though, operators will do what they can to make spectrum access complex, to preserve a final moat in a market of 10+ years of continued reduction in average revenue per user.
https://www.ofcom.org.uk/manage-your-licence/radiocommunicat...
This isn't nationally auctioned spectrum (which gets bid up to billions, then operators have to pay those fees into government coffers).
How complex / large is it of an installation? How comparable (or not at all) to setting up a large scale wifi network? How complex is the maintenance? Team size for installing / operating vs number of people served?
Everyone’s phone has a custom sim card?
Thanks :) Truly curious about this.
The only feasible alternative was 900 MHz WiFi which would have been similar, but lower throughput and much less available technology, whereas LTE modems are cheap and abundant.
It was deployed about a month ago and so far so good. It's data only, and the server the EPC is on just acts as a gateway.
Due to the conditions, the eNB is indoors. Installation of antennas was done by station carpenters as I was not allowed on the roof without training :). I am a physicist, not a telecom engineer but it was not too complicated.
- setting up a mobile network is quite different to a WiFi network in some ways, but perhaps a little more in line with a complex large-scale WiFi network. Mobile networks are architected around a "core network" which manages mobility and user traffic, and a "radio access network" which connects the base stations to your core network. The "core" is a fair bit more involved than a large-scale WiFi network setup, at least in my experience. You will need domain knowledge of 3GPP networks, and that's sometimes hard to get hold of, at least outside of traditional mobile operators and vendors. That can be a barrier.
- In terms of maintenance, a well-built RAN should "run itself" for the most-part. You'll want some monitoring on equipment. If you are using modern software-based base stations, they will run on Linux. Treat this like any large at-scale fleet deployment of Linux servers. Keep them patched and plan your maintenance windows for reboots etc. Your core network itself will realistically be a bunch of Linux servers to provide network functions. You'll have the usual periodic maintenance issues keeping up a bunch of complex services that you don't always fully understand, and the temptation to never update anything, as "it's working right now".
- The number of people you need for installing depends on skill sets. You'll need some experienced riggers to install macro sites on masts by climbing the masts. But you also need people who can pour concrete to get masts into the ground. And people who can install masts. You'll need someone who knows some DC electricals and can get everything powered up. You'll need some radio knowledge to plan out the network and check the antennas are pointed in the right directions and with the correct tilts. If you outsource this to a subcontractor, they can probably get the same people who do commercial networks to do it, but that will cost you dearly, and you'll never quite know what happened or how to fix it if something goes wrong!
- To operate the network I guess it's not a huge amount different to any other complex IT system. If you build out your core network well, you can serve a few thousand users without too much trouble, with minimal people. Once you start to scale beyond a few thousand users, you have to scale up the core and architect it a bit better. There's some routine monitoring and maintenance, and the usual things you need to do in any production environment, but in general it's not too horrendous. If you go down the "big vendor box" route like carriers do, they'll take big complex managed services to keep everything in check, but have far fewer really good network people on-staff. The biggest issue you'll have in terms of staffing up to manage it is getting the breadth of knowledge and skills needed to have access to the right range of skills as needed - legacy telecoms can get complex fast. If you are having an issue with IMS for 4G calling (VoLTE), you might only need 1 person, but that's in addition to the 1 3GPP core expert you have, the 1 IP networking expert you have, etc.
- You need to put a custom SIM into every device, and set up a PLMN identity for the network, which is just a 5 or 6 digit number that identifies the network to handsets. The SIM tells the phone what network it should try to join, and contains the crypto keys used to do authentication with the network. You can often get a PLMN allocated by your national telecoms regulator, or use one in the 999/xx range, which are set aside for private, uncoordinated use.
I have recurring daydreams of booting up a fiber ISP or WISP or (thanks to this post) a micro cell network, but peeking at the real-world implementation of those is a good way to remind myself that there's a ton of complexity that I shouldn't underestimate :-) i.e. it helps to keep those dreams "grounded".
I've built temporary 500-people ethernet + wifi networks and I'm always curious to read what it's like to do it at a larger scale. Thanks again!
There is complexity in this, but remember here you're talking to people who chose to get deep down into the tech in every component out of a desire to learn, do it themselves, and save money!
What I didn't mention was I built and ran that network effectively by myself (modulo mast climbing), with support of a few others who wanted to learn the ropes.
A fibre ISP is absolutely achievable and there's been a few posts about those on HN recently. Depending on how you go about it, it's absolutely feasible to build out your own fibre GPON network. Heck I know people doing this who have absolutely no background in networking, but have learned the practical skills of splicing and hired in the networking knowledge to support them.
A WISP is a bit simpler to get going than a cellular network, but you can also build one using cellular (that costs more). The big issue WISPs encounter is scaling their business and customer base up - it's easy to do lots of little point to point links in "customer obsessed" mode where you set out infrastructure to reach each rural customer. It's far harder to deliver a great service to these customers, especially as you start to distribute service from these points to multiple customers. A lot of WISPs end up with pretty messy flat networks they can't then scale up, and can't easily augment with fixed fibre to give themselves more capacity.
You absolutely can start your own ISP or WISP. I won't go so far as to say you should, because to evaluate "should" you'd need to understand the local offerings and competitors and regulatory landscape, but it's definitely possible. In the UK, I believe from memory that something like 2 in every 3 kilometres of fibre to the premises has been laid by "non traditional" providers or new entrants, independent of the big telcos.
Your own cellular operator is not impossible, but the scale you need to get to before you have a sellable product is the issue. You need to be (or use) a fibre ISP to get backhaul in. You need to understand site leasing and access arrangements. You'll need to be able to do radio planning and get spectrum access. You'll need billing and customer support and fault resolution. Managed services can help, but you'll rapidly see your revenues drain that way.
In the US there are a number of smaller state-level cellular operators, who effectively do all this themselves. I wouldn't recommend trying to run a mini mobile operator as a business just yet until the supporting ecosystems get better able to serve smaller scale customers though - the rise of private networks will change this, but everyone is still thinking of national scale for now.
For context, I’m in Canada where the ISP competitive landscape is dire. In the province of Quebec where I am, there are “debates” as to who should manage the government-installed electricity poles and be allowed to run any cable on them.
Actually, it’s the main national telecom giant who ended up managing those poles… Many small towns’ high speed (i.e. dsl) projects are stalled because of this.
I’ll stay on the lookout for an opportunity. :) Thanks
Not saying it would be easy - these sound like deeply entrenched problems to resolve - but often showing precedent for how it's done better elsewhere can help spur Commonwealth governments on.
In the UK, you would want to point them towards the Access to Infrastructure regulations, and the regulator's approach to "duct and pole access" - https://www.ofcom.org.uk/about-ofcom/latest/media/media-rele...
In the UK the "national telecoms giant" has to give equitable wholesale access to ducts and poles, and this is being used to lay fibre to the premises in rural and urban areas.
If you’ve done this, you could do the WISP / private LTE network. Will you likely need to do a lot of research and reading? Yes. Will you occasionally make potentially costly mistakes? Yes. But will you be successful if persistent? Yes!
As someone who owned a small WISP back in the earlier days of the Internet when finding guides was hard to do and has done a private 3G network for fun, it’s definitely doable if you set your mind to it.
Very weird that the ubuntu article talks about how easy it is to do this and makes no mention of spectrum license concerns.
However, those provisions are made in order to ensure a good/fair access to anyone, and therefore to prevent a single user or single technology from overusing those bands which are meant to be shared. For that purpose, there are associated restrictions (in terms of power/EIRP, duty-cycle) and/or mandatory sharing approaches (Listen-before-talk, detect-and-avoid, etc.). In the case of Wi-Fi, CSMA/CA is a form of listen-before-talk.
Unfortunately, mobile technologies defined at 3GPP (GSM, HSPA, LTE, NR) are not designed to be used in such a way (i.e. they don't have any sharing mechanism such as LBT and they require _by design_ dedicated/licensed bands), which by the way implies some kind of specific coordination at the country borders where two operators are using the same channels... (you might look at ECC recommendation 15-01 for an example of PCI sharing).
LAA is a way to have an LTE carrier within the (shared) 5 GHz band, but it has to rely on an anchor carrier for signaling, which requires licensed spectrum. Multefire is a fully-unlicensed solution, but I doubt many UEs (smartphones) support it, and anyway because it must implement the same power limitations and LBT as wi-fi in order to comply with regulations I doubt it would be much better than wi-fi... (maybe it would in some specific case where deterministic QoS is important)
One more thing : keep in mind that a typical 3G/4G/5G macrocell site (e.g. around 65 dBm EIRP per carrier) is something very expensive : your mileage may vary but it can easily be around 100000 € / site when some construction is required.
I want to add, as I said in my last comment that 5G NR allows for 5Ghz to be used as primary carrier, it was controversially included in the standard. A study from earlier this month showed LAA apparently doesn't play too well with wifi nearby: https://www.cs.uchicago.edu/news/article/laa-wifi/
WiFi is a whole different kettle of fish - it's designed to be used by multiple independent access point operators simultaneously, with the ability to change frequency if needed based on the interference observed. It's designed to try to deliver good performance by listening before transmitting etc, to avoid transmitting over another device, to avoid a tragedy of the commons scenario where selfish devices end up rendering WiFi unusable for everyone (including themselves), through refusing to yield time to devices transmitting on other networks.
NR-U and LAA etc don't generally play according to the same rules, as they're standards arising from the world of exclusive spectrum access, and coordination of base stations by one operator - in the world of cellular, the base stations allocate uplink channels for their clients. That doesn't work in WiFi with multiple networks in the same approximate location, hence they need to try to prevent interference and cross-talk.
I believe CBRS band 48 (3.5Ghz) is lightly licensed but I don't remember if you can set it up as a primary carrier on LTE.
I really really want to see real world usage of NR-U and as a possible replacement of WiFi.
In an ideal world, your radio manufacturer and software vendors would have appropriate patent licenses in place.
For this and other reasons (handset support being commercially problematic since carriers want to preserve their dominance), I don't see NR-U really replacing Wi-Fi. The friction to joining a device to a network is also far higher, and there's much more complexity in running the network and architecting a suitable core network and user plane functions and keeping it all running. WiFi really is a lot simpler in many ways.
I was hoping for some exemption or special arrangement on the patent issues for consumer private 5G Network. WiFI just sucks, comparatively speaking. Including WiFI 6E. And judging from the ways they are doing things I have very little hope for 802.11ay and 802.11be ( WiFi 7 ).
Outta curiosity, why do you say 6E sucks?
It is indeed an innovative way to give access to spectrum, but it's a pity it has been done in this band (which had a huge potential for usual operators in terms of site reuse).
I suspect in Europe a light licensing approach such as CBRS might be considered in higher bands such as 26 GHz...
Transmitting over radio waves is a highly regulated privilege. There are a few ranges that are open to public (i.e. the bands used for Wifi and BT) with devices that need to be certified to ensure that they transmit only in the narrow permitted ranges, but in most frequency ranges (including the LTE/5G ranges) it is illegal to operate a transmitter without an explicit license.
We need more and wider unlicensed bands, there's no reason for most of this regulation anymore.
Maybe if there’s enough demand for workplace private phone network, such laws could be passed to run 5G or 4G as Wi-Fi alternatives.
i suppose if you only had relatively low data rate applications you could use 900MHz, but there's a dearth of CPE. 900MHz unlicensed has slightly more bandwidth than a single 2.4GHz wifi channel.
In addition, in many countries the TVWS regulations only cover specifically authorised devices which adhere to TVWS standards (which 3GPP doesn't), and create a whole host of challenges for the client devices (handsets), which don't understand TVWS rules, and need their transmit power to be controlled by the base station, which isn't necessarily aware of the client location, or authorised within TVWS rules to query the TVWS database on behalf of the client.