5G as an enterprise LAN / Wi-Fi replacement is a myth

Introduction

There are at least 10 reasons why 5G will not be a viable WLAN (wireless local area network) technology for mainstream enterprise. Despite recent claims to the contrary, it is not an alternative to Wi-Fi in offices, hospitals, apartment blocks or similar locations. 

Enterprises, investors, policymakers and vendors should be extremely skeptical of assertions 5G will displace mainstream Wi-Fi uses. Indeed, they should question the credibility and honesty of those uttering such claims.

There will certainly more deployments of indoor cellular (including private and neutral host networks) in future, but these will almost all be incremental and not substitutional to Wi-Fi. They may be used for IoT/OT uses, but typically these will be entirely new. 

4G / 5G technologies will not be integrated into most laptops or tablets, despite hype.

This post looks at why 5G cannot replace enterprise Wi-Fi - including numerous obvious reasons - and then examines why the cellular industry (which mostly understands the problems) is pretending otherwise. What's the story behind the unrealistic fantasy?

(It's quite long. Get a coffee first.)


What is wireless used for in enterprises?

Before drilling into the specifics of 5G, it is worth looking at how and why wireless gets used in enterprises at a local area. Local area here means a single office or site - whether that's an office block, a supermarket, a hospital or a factory. Some locations have multiple LANs across several buildings on a campus network, such as a university, corporate HQ site or major new property development.

(By contrast, WANs run over wide areas, such as between a retail chain's stores and warehouse sites in different cities, or linking a multinational bank's offices in several countries. Huge locations like smart cities and airports are somewhere in the middle).

A top-level list of local wireless uses, often with separate infrastructure, includes:

• Local IT / Internet connectivity - this is the main LAN space, dominated by fixed ethernet and Wi-Fi. It connects PCs, laptops, deskphones, tablets, conferencing gear and various other computing products, either to the business's own servers or to the Internet and cloud. It is also good for private use of smartphones.
• Coverage extension of public mobile operator (MNO) services onto private property, where outdoor-to-indoor signals don't reach. This uses various forms of distributed antenna system (DAS), repeaters, small-cells etc, typically installed today only in the largest buildings. Essentially, this enables local smartphone connectivity both to the telco's services (eg telephony) and to the public Internet. In some cases Wi-Fi is used to "offload" data that could normally have gone over the carrier network. Note: genuine offload is a tiny fraction of total smartphone data traffic - see this post for more (link)
• Local IoT connectivity (connecting building automation systems, HVAC, entry control etc. This can be further divided into
• Static IoT - things that don't move around, such as sensors, door controls, CCTV cameras & aircon units
• Mobile IoT, for instance credit card terminals, robots, wearables, asset-tracking tags etc
• Local OT connectivity - operational technology, often business/safety-critical with a need for realtime deterministic control, such as industrial machinery, process controls, medical equipment and so on.
• Local voice connectivity - especially walkie-talkies and private two-way radio, which are now starting to be replaced with cellular alternatives.
• Other local uses - numerous sectors have their own niche wireless requirements, maybe linking to public safety / first-responders, broadcast, audiovisual systems etc

While some of these categories overlap (for example, smartphone connections), others remain pretty well-defined in practice. Yet often, they get conflated, especially in discussions about the future roles of 4G/5G cellular networks, whether run by mobile carriers, or new/specialist indoor operators and the enterprises themselves.

This post is specifically about the IT/LAN/Internet access use-case. I think cellular has a lot to offer IoT (especially mobile IoT) for enterprise, as well as OT in industrial settings. We will also see more indoor / premises neutral-host networks (NHNs) both for coverage and private onsite voice/smartphone access. However, none of those generally gets classed as "LAN" connections.

(SAVE THE DATE: I will be running a private workshop in London on July 9th about NHNs, looking at both indoor and wide-area / metro / rural uses and deployment scenarios)

Why can't 4G/5G be used for wireless LANs instead of Wi-Fi?

At the heart of this debate is whether 3GPP cellular technologies can be used for local-area computing networks, especially for laptops, tablets and private smartphone use. Can it replace fixed ethernet and especially Wi-Fi connections? Will future PCs connect to the Internet via 5G? I'm being asked this by various of my clients, so it's worth going in to some detail here (and obviously, more detail & analysis for paying advisory customers)

This is not a new discussion - the 3GPP vs. IEEE standards war has waged for decades. I've addressed the topic multiple times, whether that's been about in-home usage (link), debunking the "5G will kill WiFi" myth (link) or discussing the important role for private cellular in industry and the need for local spectrum licensing (link). 

I can see at least 10 reasons why cellular (whether provided by MNOs as a service, or owned by the business or an NHN provider) is not a suitable IT LAN technology for enterprise:

• 13bn installed base of actively-used Wi-Fi devices today, of which only smartphones typically have cellular radios. Some have shortish replacement cycles (eg tablets) but others will last for 10+ years. They will need to be supported in-building.
• A tiny fraction of laptops & tablets have in-built 4G radios today. Despite the hype, this will not change significantly with 5G. Customers won't pay more for them, and manufacturers don't want the margin hit. We might see 10-20% penetration, but I'm doubtful (This is a whole other "10 reasons" post in its own right...) Wi-Fi remains primary.
• Plenty of other devices will never have cellular connections (5G printers? Servers?!). The number of Wi-Fi devices is exploding in IoT as well - from smart-speakers to lighting to interactive screens and terminals. Add in new low-power Wi-Fi for things like headsets (and a separate battle between Wi-Fi / BLE / ZigBee which cellular doesn't even have a toe in). Again, Wi-Fi remains primary. High-end/critical IoT devices may actually adopt passive optical LAN connections, rather than any wireless technology.
• Private 4G/5G networks are not just radios. They need core networks, control software, and maybe SIMs/eSIMs. The average IT department does not want to, or have the skills, to deal with all this, compared with installing some ethernet wiring and some Wi-Fi APs.
• Almost no businesses want to deal with the complexities of private / public cellular interconnection, roaming, regulation (lawful intercept?!) and so forth
• Even if some IT departments want to go towards 4G/5G connectivity, they still have BYOD policies, and guests, contractors and tenants who will keep desiring (& often expecting) Wi-Fi
• In-building 5G is going to be hideously complex anyway, especially for mmWave frequencies. Installing small cells also needs fibre backhaul, power etc. in the right places, whch may be different locations to Wi-Fi APs.
• Ironically, in-building 4G small cells usually need wired LAN connections to connect them. In future, it might even be possible to use Wi-Fi6 as backhaul, as it should have good-enough deterministic QoS for the time-sync requirements.
• The world would need, I estimate, 100-300,000 more enterprise cellular specialists for designing, installing, maintaining & operating 5G LANs. And AFAIK there aren't even proper training programmes, or certification schemes. That's a decade or more on its own (and probably a big opportunity for some) 
• Indoor wireless coverage is difficult and variable. Radio is absorbed by interior walls, partitions, furniture, insulation, pipework etc. Giving QoS guarantees is almost impossible. Few design, planning and testing tools are available.
• Device-to-device use cases for Wi-Fi are not easily replicable with cellular. Maybe in the future.
• User perceptions of Wi-Fi and cellular, and behaviour around it, are entrenched and will take years to change, if ever.
• Patent & royalty costs for cellular are higher, as well as the extra chipset costs.
• Unknowable new security / threat surfaces (and the fact that Wi-Fi security is often integrated with the enterprise's identity & threat-management systems today)

I could go on. Some of these will change, some will have rare exceptions, and some industries will have particular local requirements for whatever reasons. But the underlying story is clear: 5G is not a Wi-Fi replacement for the enterprise. 
 
This should not really be a surprise to anyone. I honestly find it hard to believe that most people involved in networks/telecoms don't realise at least 4 or 5 of these points off the top of their heads.

Historical note: I've been skeptical of cellular-enabled laptops since 2006 (link). I wrote a full report in 2008 (link), which was actually far too optimistic (I predicted 30% attach-rate by 2011) despite being criticised as too-negative by the cellular industry. Most of the arguments remain valid for 5G.


So why the hype?

What's a bit baffling is why the 5G/WiFi replacement fantasy is becoming more common. Even AT&T's CEO was quoted at the company's financial results event (link) as saying "It’s serving as a LAN replacement product". Other 5G-centric commentators have said similar things.

To be fair, in some cases it will be genuine ignorance, although frankly anyone that clueless about enterprise networks shouldn't be making pronouncements anyway. Another more important issue is the conflation of all the different use-cases for connectivity (as above), and people conflating the LAN, offload and IoT domains in particular. Through that lens, the AT&T statement could (very generously) be considered applicable to some IoT scenarios.

Yes, 5G has a long-term role in some industrial verticals, especially with time-sensitive networking and private control of core and/or radio & spectrum. Neutral-host cellular will be important indoors too. But controlling robots & process machinery, or doing asset-tracking in a hospital, is not the same as accessing SaaS applications from a laptop or tablet, or local IoT applications from billions of devices with local gateways. Neither is using a new 4G/5G CBRS or local-spectrum network for "reverse roaming" or "MVNO onload" really a LAN business either.

But I think there are a few other more cynical reasons in play too:

• Embarassment over mmWave's poor indoor penetration (despite the rhetoric), meaning Wi-Fi is an essential in-building complement for any 5G FWA deployment. This applies in residential use, but also for businesses too. Pretending that some sort of 5G outdoor - 5G indoor hybrid could fix this might spare a few blushes.
• Cost & complexity of future indoor 5G deployments: Reality is biting. Existing indoor systems are going to be hard to upgrade to even 3-4GHz bands, let alone adding mmWave and massive-MIMO support too. It's not just the radio elements, either - how exactly are carriers going to offer QoS / network-slicing over someone else's indoor wiring and antenna infrastructure? See this eBook I recently wrote for iBwave (link) for more details. Basically, if the telcos are going to help pay for 5G indoor connectivity, then new use-cases/revenues are desperately sought, beyond just MBB coverage. A "managed 5G LAN" line on a spreadsheet likely looks appealing, even if it's an exercise in wishful thinking.
• Bluster & hype aimed at regulators considering the 6GHz or other bands for unlicensed use (& thus mostly more Wi-Fi). The US FCC and various European regulators seem minded to add another large band (500-1200MHz) to the unlicensed systems arsenal. Taking a public stance of saying "Oh, 5G could do all those use-cases as well - how about normal exclusive licenses for that band instead?" fits the political narrative, even if it doesn't fit reality. 
• Some 3GPP fundamentalists' dislike of Wi-Fi and unlicensed spectrum generally, or non-telco controlled networks, explains some of the comments. I've seen posts on LinkedIn saying "I wish Wi-Fi would go away", and similar. They have long fantasised about MNO-managed cellular LANs , in the same way that some Wi-Fi (and satellite) fundamentalists think they can replace mobile networks. They're all wrong. (And so are the 5G FWA folk claiming it's a mainstream alternative that could replace fibre or cable).

Conclusion

So to sum up:

• There's lots of different uses for wireless networks in enterprise, whether in individual buildings or across larger campuses. Ignore anyone who groups them all together.
• IT-centric LAN connections, for normal computing devices connecting to the Internet, cloud or local servers, are dominated by ethernet - either using fixed cabling, Wi-Fi or occasionally optical LAN. Smartphones connect both by Wi-Fi and cellular, where indoor connection is good enough.
• A handful of laptops and tablets can use 4G connections today, although few owners even bother to sign up for data plans. A slightly larger handful will have integral 5G in 5 years time, but most will just stick to Wi-Fi only. They will need to be supported in all the same locations as today, plus many new ones (eg public transport & retail).
• Private 4G and 5G networks come in many varieties, with a huge range of shared/local spectrum options being considered by regulators (link). Most, however, are not aimed at LAN use-cases, but more oriented to IoT/OT/indoor cellular coverage requirements. In those instances, Wi-Fi has limitations, for instance in applicability to robots moving around a large factor or warehouse.
• Some industrial/critical use-cases are not ideally suited to unlicenced spectrum, even with the better performance of new WiFi6 deployments. Given that the WiFi industry doesn't (yet) have a licensed-band version, then cellular is a likely option instead. 
• Neutral host cellular networks are very exciting future developments, both indoors and out. But they're not going to be LAN replacements either.
• Operator 4G and 5G networks are very important to extend in-building, especially if telcos want to offer new network-slicing or QoS products that don't just work outdoors. However, upgrading existing in-building coverage solutions to 5G is hard, expensive and has many unknowns. Many small buildings don't have indoor coverage solutions at all today. The mobile industry is casting around for new revenues, as well as costs. One takeout: end-to-end network slicing is largely mythical, and will need to work over 3rd-party Wi-Fi indoors.
• We will also see various forms of Wi-Fi + cellular bonding, with devices connecting to both networks simultaneously. That's for another post.
• As with all areas of 5G hype, there's an "it'll solve world hunger", "one-size fits all" pitch to politicians, regulators, investors and media. It needs to be called out for its disengenuousness.

Overall, the key takeout: 

Private/enterprise 4G and 5G networks have lots of potential future use-cases & market opportunities. Replacing Wi-Fi for IT/Internet access LANs is not one of them.

Note: if you're interested in deeper analysis, or a private workshop / advisory engagement on this topic, please drop me an email at information at disruptive-analysis DOT com, or contact me via LinkedIn or Twitter.

Also - on July 9th, I'm running a London private workshop on Neutral Host Networks, together with Peter Curnow-Ford of Viatec Associates. Drop me a message if you're interested, and look out for full details & registration coming very soon.

Thoughts on in-building wireless - and an upcoming client webinar

I've been pondering some of the side-effects and necessary enablers of the accelerating wireless evolution path we're seeing. As well as spectrum issues I've covered a lot recently, deploying indoor infrastructure is going to be another one of them. 

It is not a new assertion that indoor networks are important for enterprise. The frustrations of poor indoor cellular coverage are universal, while businesses of all types need to provide employees and guests with high-quality Wi-Fi.

(I'll cover trends in home Wi-Fi in a later post, while I've already written about industrial facilities in a number of previous ones, such as here, as the issues are as much about spectrum as about infrastructure and planning.)

Various solutions abound for providing good signal indoors – distributed antenna systems (DAS), small cells, or even just deployment of lower-frequency bands in outdoor networks, with better penetration through walls. Yet costs remain considerable, especially as usage increases near-exponentially. Upgrading or retro-fitting existing installations often requires hard economic decisions, given that most such investments are not directly “monetised”. Suitable expertise, foresight, planning tools and ongoing monitoring/reporting are important.

The future, however, will accelerate the role of in-building/on-site wireless connectivity – in both predictable and unpredictable fashion. If we consider what a building might look like in the year 2030, say – and how it may be used and occupied – we can start to see the challenges and opportunities.

As well as today’s well-known and well-described uses of wireless (smartphones and laptops on Wi-Fi and cellular networks), we can expect to see a huge number of new uses emerge. This means that today’s implementations will require future-proofing, to support the unknowns of tomorrow. For example, consider the implications of: 

• IoT deployments for smart buildings, such as a proliferation of sensors for heating, security, or the operation of elevators. These may require better coverage in unusual places – in ceiling voids, lift-shafts, basements and so on. Bandwidth and latency requirements will vary hugely, from life-critical but low-data fire/carbon monoxide sensors, to networked video cameras, or once-an-hour reporting from water tanks.
• Moving devices such as robots or automated trolleys, delivering products around the building. While some will be fully-autonomous, others will need constant wireless connectivity and control.
• 5G networks will be deployed from around 2020, with further evolutions in following years. These may be extremely demanding on in-building coverage solutions, especially as some networks are likely to use frequencies above 6GHz – perhaps even as high as 80GHz. Extensive use of MIMO and beam-forming may also add complexity to indoor implementations. (A new variant of WiFi known as WiGig also uses 60GHz frequencies)
• Likely huge growth in narrowband wireless, connecting low-powered (but maybe very dense) networks of sensors or other endpoints. These may use 3GPP technologies such as NB-IoT, or other options such as LoRa and SigFox.

All of these trends imply very different traffic patterns. It is not realistic just to extrapolate from current usage – robots may go to places in buildings where humans do not, for example. Mobility requirements may evolve – and so will regulations.

It is not just new classes of device and application which will need to be supported by well-designed coverage infrastructure, but also new classes of service provider that need to access them.

• The advent of new unlicensed or shared-spectrum models of frequency allocation (eg CBRS in the US, or MuLTEfire) may mean the arrival of new operator types – dedicated IoT solutions providers that “bring their own wireless”; enterprises acting as their own local on-site MNOs; various models of “neutral host” and so on.
• Private enterprise cellular networks are starting to become more widespread. Some governments are allocating spectrum for industries like utilities or smart-cities, while equipment vendors are offering optimised enterprise-grade cellular infrastructure.
• Potential future regulations for emergency-services wireless connections. Police and fire authorities are increasingly using broadband mobile, both for humans and remote-sensing devices.
• Distributed-mesh service providers, that operate as decentralised networks with micropayments, or as community initiatives. Some may use blockchain-type arrangements for shared-ownership or membership fees.

One of the unknowns is about the convergence (or divergence) of different network types. On one hand, cellular networks are embracing Wi-Fi for offload, or for multi-network aggregation, especially as they worry that returning flat-rate data plans may stress their networks. On the other, some networks are looking at running 4G/5G in unlicensed spectrum instead of (or in addition to) Wi-Fi. Yet more service providers are adopting a “Wi-Fi first” approach, reverting to MVNO models for cellular where needed. Future permutations will likely be more complex still. All will (ideally) need to be well-suppported by indoor wireless infrastructure.

For property developers and owners, the quality of indoor networks is increasingly key in determining valuations and rental occupancy. Already seen in hotels, and office new builds, it will be important for today’s new constructions and refurbishments to support adequate flexibility and headroom for the next decade or more.

This takes on further emphasis if you consider the trend towards “buildings-as-a-service”, exemplified by organisations such as WeWork. These new classes of facility often incorporate wireless connectivity both as a billable service element, but also to enable their owners to manage the properties effectively, in terms of energy-efficiency and security. Other forms of monetisation and data-analytics around wireless location-sensing/tracking are also becoming more important.

Lastly, in-building challenges will be driven by the specific location and industry, which themselves may change in nature over the next decade. New building materials, construction practices and regulations will impact wireless in unpredictable ways – more metallic insulation perhaps, but also perhaps robot or pre-fabricated construction allowing wireless systems to be installed more easily. Individual industry verticals will have their own shifts – what will retail stores look like, and how will customers behave, in the era of home deliveries by drone, but more on-premise “experiences”, perhaps with AR/VR systems? What workplaces of the future look like, in an era of self-driving vehicles? Industrial facilities will become increasingly automated, with the largest uses of wireless connections being machines rather than humans. Hotels and airports will see shifts in data connectivity needs from employees and visitors, as application usage shifts.

Small cells look certain to play a more important role in future, and Wi-Fi is going to remain the most important indoor technology for many users and businesses (ignore the fantasists who think it's at risk from 4G / 5G - see my earlier post here).

There are no easy answers here – even if you construct good scenarios for the future, undoubtedly we will be surprised by events. But some form of upfront discipline in designing and building indoor wireless solutions is ever more critical, given the unknowns. The more future-proofing is possible, the lower the potential risk of being caught out.

  

On October 5^th, at 3pm BST / 4pm CET / 10am EDT, I will be presenting on some of these topics on a webinar for client iBwave. A link to the event is here