Up until now this was mostly an annoyance, largely because it was a personal problem.  By that I mean it was an inconvenient truth that individuals discovered when they bought a consumer wireless product, whether that was a Wi-Fi access point, a cordless phone or a mobile headset.  As these were generally low cost, discretionary purchases, users either took them back, put them in a cupboard and forgot about them, or worked around the problem by moving the appropriate access point.  For the more technically engaged, a raft of companies grew up making repeaters, range extenders, power amplifiers and directional antennae, allowing users to exacerbate the problem by swamping all of their neighbours’ installations.

In the last year people have started to take the middle word of “short range wireless” rather more seriously.  That’s come about as governments around the world have mandated deployments of smart meters.  Whilst no-one cared too much if a consumer product didn’t work, smart meters are a different kettle of fish.  They need to be able to connect with the other components of the smart metering wireless network in the home in order to send consumption data back to the utilities.  They have to do that reliably and regularly over a period of many years.  And they need to be able to cope with a wide variety of homes - from small bungalows to multi-storey apartment buildings.  All of a sudden that “range” word is getting a lot of attention.

The problem is that the wireless standards being considered don’t cover 100% of different homes.  Any one standard probably struggles with covering much more than 75% of potential homes.  That’s a big problem for regulators and civil servants who have a very black and white view of life - when a mandate says “all”, they assume that means every last home.  So what can they do?

In an ideal world the governments who are mandating smart metering should have started to think about the problem ten years ago.  That would have given them time to release an appropriate chunk of RF spectrum and work with standards groups to define a suitable protocol.  Needless to say, they didn’t, which gets us to where we are today with a raft of competing short range wireless standards all arguing that they have the best solution.  That’s marketing weasel words; none of them do, at least in their present form.  Each has made inevitable compromises between range, security, power consumption and bandwidth - that’s what wireless standards are all about (for more on which, buy the book or read some of my previous posts).  It doesn’t mean that they couldn’t evolve to solve range, but that’s not been their first priority.  Goverments also have another problem, which is their politics, as there are certain civil servants involved with smart metering in Europe who have very limited ideas regarding what a standard is and whether anyone is allowed to use some of them.     

But range has become top of the list for governments and utilities, not least because it’s one of the easiest things to measure.  Or is it?  Surprisingly, very little work has been done to evaluate it.  One of the best analyses comes from Australia.  Australia has a particular problem in that they install meters in metal boxes on the outside of a house - something that most RF engineers refer to as a Faraday cage.  The report looked at the effect this has on the range of ZigBee at 2.4GHz.  Sadly the report isn’t public, but its main conclusions have been disclosed at a number of conferences, which are that the range from ZigBee devices was perfectly adequate in most homes, but that they would benefit from have an additional repeater somewhere in its middle, operating at 100mW 

The main conclusion, which is that ZigBee worked most of the time, tended to get eclipsed by the predictable recommendation of upping the power, based on the old principle that if you shout louder, you’re more likely to be heard.  It’s a less than valid corollary that is far more prevalent than it deserves to be and decidedly problematic in the real world.

Because adding a repeater as a solution is not as easy as it sounds.  The cost of adding it is one issue, but a bigger one is how to power it?  Today the only products that a utility needs to monitor your power consumption are an electricity meter and a gas meter.  The electricity meter is self-powered and the gas meter has a big battery in it.  If a repeater is added next to the electricity meter, where it can be powered from the main electricity supply, it does nothing to increase the range.  But if it is located some distance from the meter, then the question arises of how to power it?  If it plugs into a socket, what’s to stop a user unplugging it at some point?  How many household products can you think of that have remained permanently on and powered for twenty years or more?  And a device in the middle of the house transmitting at this power level is unlikely to endear itself to the electromagnetically sensitive members of the population.  Although a technical solution, it’s not practical for large scale deployment.  What the industry needs is an answer that doesn’t require the installation of extra boxes.

A much less focused piece of research is currently being undertaken by the UK government, which is looking at radio range at different frequencies for a variety of different types of house.  At least they think that’s what they’re measuring.  The actual trial is looking at carrier wave propagation, which is rather different.  Part of the rationale behind it is to provide an evidence base for their eventual choice of HAN technology.  The problem with this approach is that propagation is not the same as range.  An earlier generation of physicists, notable Friis, have already evaluated propagation and discovered that the power received at an antenna decreases with the square of increasing frequency.  Hence this piece of research will conclude that 2.4GHz, which is where ZigBee operates, has the poorest propagation of the frequencies being investigated.

It’s an outcome that doesn’t tell us anything much about range.  Although range depends on propagation, it also depends crucially on the way a wireless standard uses that frequency. Wireless standards are designed to manipulate the properties of the transmission to extend or decrease range.  They do this by employing coding gain, channel width, spread spectrum techniques, diversity, directional antennae and a host of other parameters. 

Understanding this distinction is quite difficult, so let’s take an analogy, based on your car.  A simplistic view of how fast your car could go would be based on the diameter of its wheels.  If the axle turns at a particular angular velocity, then the speed is proportional to the wheel diameter.  That’s akin to classic propagation and transmit power, where the diameter of the wheel is the equivalent of wavelength (which is inversely related to frequency) and the angular velocity of the axle turned by the engine is that of transmit power. 

But that’s not how we build cars.  In a real car we also have a gearbox, which adds a similar level of complexity to a car’s speed as a wireless standard does for range.  With the gearbox present, for the same size wheel and engine rpm, you can drive at a wide variety of speeds.  The gearbox makes appropriate compromises to maximise acceleration, torque and speed depending on which gear you select. 

Even when you’ve grasped that propagation is not the same as range and has an important dependence on range, that’s still not the whole story.  Even with the same standard, range is still highly variable dependant on different chips and pcb designs.  There’s still a lot of black magic in RF design and these can affect the range of any individual product by an order of magnitude. 

I’m not sure what the Government will deduce from this study.  It may give them an indication of what percentage of homes need another technology, but I’m not convinced, as it doesn’t bring the reality of practical implementations into the study.  What it will do is indicate that there is currently no holy grail.  The more worrying scenario is that they will try to use it to ascribe a financial cost to a delay to allow them to develop a new standard.  For example, “If 2.4GHz covers 60% of properties today, 868 MHz will cover 71% in two years time, 169 MHz would cover 83% in five years time and white space solves the problem altogether the year after I retire, how much money can be saved by sticking our collective heads in the sand and putting off smart metering?  And is it enough to pay for my index linked pension?”  Answers on a postcard to your local MP…

So what are the options for smart meter connectivity?  Today, if the UK Government chooses ZigBee, they’re probably limited to fulfilling something between half and three-quarters of UK homes.  Let’s be clear that whatever its failings, ZigBee SEP 1.1 has the security, throughput and higher layer application features in place to allow deployment to start.  Plus there are multiple vendors supporting it, both at chip and device level.   No other wireless standard can make that claim today.  It is the pragmatic choice.  Any limitation around range is not an excuse for delay.  Over the eight or more years it will take to complete the smart metering roll-out in the UK technology will evolve and should be directed towards finding solution for the remaining proportion of homes.  Hence I’d suggest that governments take a pragmatic approach.  That means accepting that no solution available today will cover 100% of home, but start with one that does, then concentrate resource on adding in other technologies to fill in the missing 25-50%.

Under that plan, stage one would be to take ZigBee and target homes where it is going to work.  There’s an interesting corollary to that.  Homes where it will work are likely to be clustered together, where all of them have the same, or very similar construction.  That means that it would make sense to start installing smart meters on a street by street basis.  What’s interesting is that’s exactly what the recent Centre for Sustainable Energy report on smart metering recommended.  Not for any reason of radio range, but because of the community advantages that occur when groups of people make changes together.  That’s just good behavioural psychology.  So let’s do that - kill two birds with one stone by starting with the streets which have houses which work with ZigBee, which will keep everyone busy for the first few years of the deployment.  Then expand the smart metering deployment to other homes as new technologies appear. 

As the utilities are doing this, the UK government should be looking at what comes next, to cover the next tranche of installations.  One option is to use Powerline communications for properties where that’s appropriate.  The Homeplug Alliance has been working with the ZigBee Alliance for several years on ensuring compatibility at an application level.  It has limitations, particularly for the mobility of In Home Displays, but it can provide a solution for another group of homes.

Slightly further out, there will be time to consider a better radio for ZigBee.  Currently ZigBee uses a radio defined by the 802.15.4 standard, in a version which was ratified back in 2003.  Although the 802.15.4 standard has evolved in the last nine years, ZigBee hasn’t incorporated any of these upgrades, as it takes considerable time and money to develop new chips.  But over the time of the smart metering deployment, it should be possible to develop a new generation of radios which could have an enhanced link budget, giving them better range.  There’s quite a good chance that they could be backwardly compatible, making life easier for consumers and equipment vendors.  That would probably provide a solution which would cope with the majority of detached, semi-detached and terraced homes, which covers a large portion of the UK housing stock.

It still leaves the issue of multi-story buildings, which are particularly resistant to short range wireless, particularly if the meter is in the basement.  However, the issue of radio propagation in these buildings isn’t one that’s limited to ZigBee and smart metering.  It’s a similar concern for mobile operators, as buildings that don’t work well for ZigBee are generally equally ill-disposed to cellular networks.  Which means it’s a problem that network operators need to solve too.  Recent research claims that over 75% of mobile calls are made from inside buildings, and around 95% of data access is also done inside.  (That last figure’s not actually that surprising, as most data access from a mobile involves looking at your phone’s screen - an activity that’s closely correlated to walking into lampposts if you’re outside the home.)

A lot of research is going into solving this problem, notably by covering these buildings with distributed systems, capable of RF distribution over Ethernet or structured cabling.  This allows RF signals over the 500MHz - 5GHz range to be distributed throughout the entirety of the building.  Today most of these projects are in the research stage, although companies like Zinwave are beginning to turn them into real products.  But with investment and commitment, they should appear as viable commercial solutions in the next five years.  The beauty of this approach is that it would work with the current generation of ZigBee products, and it might even get paid for by the network operators.

The important thing is that we don’t wait until there is a perfect solution that covers 100% of homes.  If we do, we’ll never get there, as there will be no income for the industry to evolve new solutions.  Instead we need to be pragmatic.  Understand the limitations and start with what we can do.  And then use the experience and revenue from that to extend to new solutions.  There are already roadmaps and research which promise tenable answers, but they need the momentum of deployment to bring them to reality.  By working with mobile networks to solve shared problems the industry can probably move much faster.  Just look at the developments in mobile infrastructure over the last decade.  It shows what can be done when the commercial incentive is there.

Most importantly, don’t give in to the inherent risk aversion of the energy industry.  They are facing a massive step change in their level of technology and IT systems by signing up to meet the UK smart metering mandate.  Because of its degree of deregulation, the UK deployment will be one of the most complex systems in the world.  The utilities are starting to realise that and some would not be averse to applying the brakes to wait for the perfect solution.  Particularly if they believe that might be a long way away.

But it should all be possible.  If we’re pragmatic and work together, the UK will gain some world beating expertise.  Technology will get there.  Eight years ago (the equivalent of how long we are planning to take to complete the UK roll-out), ZigBee was little more than a pipe dream.  Wi-Fi didn’t exist, nor did the iPhone or the Pad.  Technology can move faster than we realise, particularly when it has something driving it.  In this case that’s a well-defined problem, with the added incentive of deploying tens of millions of real products. 

The UK has taken an aggressive stance in defining and mandating the world’s most complex smart metering system.  It should show its resolve in moving forward by taking the risk and stepping up to develop the appropriate new technologies alongside that deployment.  If it does, then UK plc will gain valuable expertise in demonstrating and selling smart metering to the rest of the world.

This bizarre situation arises from the decision back in March this year, when PG&E worked out what to do with their electro-sensitive customers who were demanding that they weren’t radiated with emissions emanating from their smart meters.  PG&E put forward a proposal to make customers pay for non-smart meters, charging somewhere between $135 and $270 a year for the privilege of having a good old-fashioned meter reader come round and leave them a note to say they were out when he called.  The double whammy benefit that none of the media appeared to pick up is that the $270 charge would eat into these user’s mobile phone bill, so they’d have less money to spend on getting radiated by phoning their local papers to campaign against smart meters.  More affluent customers could have the gold plated option of paying several thousand dollars to have their meters moved to the top of local telegraph poles, or buried underground.

PG&E reckoned that this option would be taken up by 185,400 customers.  (I don’t know how they got to that precise figure. Although by a strange coincidence, 1854 is the year that Texas was connected by telegraph to the rest of the US, putting in place the telecoms network that Enron would use so effectively 150 years later.)  Anyway, this number presented PG&E with a problem.  185,400 is not a lot in terms of commissioning a special non-wireless meter.  So they were faced with the prospect of having to pay more for a non-smart meter, wiping out a substantial part of that $50 million annual windfall from their more sensitive customers.  Today they announced a solution - they’d supply the same wireless smart meter, but turn the radio off.  Enter the wirelessless meter.

Over the past few years there have been a number of rumours about smart meters being shipped with the radio disconnected.  That was because they’d been specified to include a radio, but no-one had ever intended to connect it, because it was way before the standards had been completed and it would probably not have worked.  But because it was on the procurement tick-list, the chips were fitted, but never turned on.  I’m not sure whether these stories are apocryphal - they covered several different wireless standards and allegedly several million meters, but PG&E’s decision means that they’re going to be true in the future.

For the different standards and chip companies supporting them, this opens up a fascinating new market opportunity.  Instead of competing to claim they have the best implementation of the standard, they now have the chance to compete on the basis that they are less effective than any other standard.  It doesn’t matter what your range is (unless it’s zero, which is now very good), what profiles you support, or even how power efficient you are.  All that matters is that you can keep quiet.  It does raise the interesting question of whether you need to go through a radio certification for a device that will never turn on, but I’m sure that the test houses will claim you do.  After all, they’ve got a living to make as well.

What we don’t know is whether these chips will be turned off in such a way that they can be turned back on.  So if a house is sold, can the new radio be turned back on.  And if so, how can it be done?  And I’m sure our PG&E’s wireless-shy community will want to know that it can’t happen accidentally and fry them in their sleep.

One important thing PG&E haven’t told us is whether these radios will need to be upgradable to support a future IPv6 based network which also doesn’t transmit.  I’m sure NIST will have a view on that, so maybe we can expect a new PAP group to consider disconnected radios.

You can’t really blame PG&E for opening up an Alice in Wonderland debate on dumb smart meters.  They’re trying to find a pragmatic solution in the face of wireless deniers.  But it does highlight the ever increasing complexity of the hoops that the smart metering industry is having to jump through.  All of which sucks up effort from the more important task of making the roll-out effective.

Is that a white rabbit I just saw jump out of my meter?

There’s no doubt that ZigBee is well placed in current smart meter deployments.  Although there are quite a limited number of real ZigBee deployments in Europe, the UK has more or less committed to SEP 1.2 for its foundation phase of national deployment and most meter and IHD suppliers were showing ZigBee products, albeit with not very many sporting a ZigBee certified logo.

Despite that, a significant number of suppliers were also highlighting support for the new Wireless M-Bus standard, which has slithered down the spectrum to its new resting point of 169 MHz.  Wireless M-Bus has always had a popular following within Germany, with an implementation based on a radio running at 868 MHz.  The shift to the lower frequency acknowledges one of the enduring complaints which the 868MHz camp has levelled at 2.4GHz solutions, which is their potentially limited range. 

Whilst 2.4GHz is a frequency that’s fine for most houses, it faces challenges with blocks of flats.  Up until now, the 868 MHz triumvirate of Wireless M-Bus, Z-Wave and wireless KNX had always given the impression that they could achieve adequate range at 868 MHz.  This break in the 868 MHz ranks does not augur well for a reasoned debate, but just increases the in-fighting and paranoia about whether any radio standard works or is ready for deployment.  That’s not what Smart Metering needs. 

Lower frequency proponents have a history of playing mischief on the 2.4GHz standards, citing their better range.  Whilst that’s technically true, it can be a specious argument.  Moving away from 2.4GHz brings other problems, not least of which is the lack of bandwidth in the lower ISM bands.  That limits the throughput which can be achieved by operating at a lower frequency.  It may not be a major issue for transmitting measurement data, but it means that features like Over the Air upgrades may be challenging.

The PR around these lower frequencies solutions generally focuses on the range of the radio, but that’s only part of what you need for a smart meter or smart home deployment.  The bigger development task is the protocol stack which brings security, power management, topology and commissioning tools to the solution.  A lot of the lower frequency standards jostling for position have relatively simple stacks.  In one sense, that’s good, as there’s nothing wrong with simplicity.  But for an application like smart metering, where security and integrity of data are paramount, these simplistic approaches look rather limiting.  The industry needs to understand that the time for talking and pontification is over.  We’re only really going to discover what works by committing to deployments, rather than pandering to academics and consultants who want to be paid for telling us there’s something better around the corner.

Wireless M-Bus was not the only contender.  The main Smart Metering show had outgrown its space and spawned a daughter exhibition and conference targeting the Smart Home.  On the exhibition floor for Smart Homes, there seemed to more floor space taken up by wireless standards that there was devoted to products.  Z-Wave were proudly demonstrating the range of products that they’ve enabled, as was EnOcean. Wireless DECT, a recent latecomer to the table were busy promoting themselves, as were wirelessKNX - another favourite in Germany.  In comparison, the ZigBee booth looked rather small and apologetic.

Around the show floor, there was the initial evidence that ZigBee may have let in a Trojan Horse by embracing IP in their Smart Energy Profile 2.0.  I’ve written about the incompatibility of IP with low power radio before and my personal view is still that it’s a really bad idea.  But the IP lobby has gained momentum, especially since the decision to allow it to run on different radios.  That was evident in Amsterdam.  SEP 2.0 is still a long way off, but I came across four separate stands with demonstrations of an early implementation.  What was interesting is that only one of these four ran on a ZigBee radio - the demo being given by Ember.  The other three were all using Wi-Fi.  And as far as I could tell, these were all using stacks from different vendors, running on different host microprocessors.  So a lot of effort is being put into SEP 2.0 by people who have no interest in ZigBee.  It’s quite clear that the Wi-Fi community see this as their chance to wrest smart metering and home automation away from ZigBee.

For those with a long memory, ZigBee isn’t the first wireless standard to get mugged by the IP fundamentalists.  Back in 2002, when Microsoft was starting to court Bluetooth, it led a similar crusade to incorporate IP support into the Bluetooth standard.  At conference after conference they would present the world according to IPv6, to the extent that it became a favourite game for delegates to lay bets on how many seconds it would be before the Microsoft speaker uttered those four syllables.  The IP lobby got sufficient traction for many man years of development work to be undertaken, some might say wasted, leading to the PAN profile, the BNEP Network Encapsulation Protocol and an Automation profile proposal using BNEP to support ANSI 1451.5.  All of which have subsequently been ignored by product and application designers.  The only significant think to come out of this IP invasion was that its major proponent became the Chairman of the Bluetooth SIG.  So maybe there’s a lesson for Bob Heile (Chair of the ZigBee Alliance) to keep a close look out for Geeks bearing IP gifts.

To some degree, it doesn’t matter too much which standard is chosen for any national or regional smart metering deployment.  Utilities have always tended to purchase proprietary versions of meters and back ends - a fact that has led to the observation that US utilities may be wasting over $2 billion is their procurement policies.  So if the UK goes ZigBee 1.2, Germany goes wireless M-Bus, France goes Powerline and Massachusetts goes Wi-Fi SEP 2.0, that will work for utilities.  What it does not do is open up a market for connected home automation devices.  The point here is that whereas utilities determine exactly what they put in your home, when it comes to appliances, it’s the consumer that chooses.  Which makes it is really important for the industry to coalesce on one single radio standard.  And I emphasise radio, as it’s the physical layer that is important here.  Wireless standards are complex, which means they are both difficult and expensive to implement.  They’re also difficult for consumers to commission.  Most appliance manufacturers are not familiar with them and don’t want to have to support multiple options for different markets. 

Today you can buy some top of the range domestic appliances with Wi-Fi, Bluetooth or Z-Wave, but they’re expensive prosumer products for the geeks.  A lot of the speakers in the smart home conference were promoting a vision where you can lounge in front of your TV and use your smartphone or tablet to turn off the annoying bleep on your dishwasher.  (In case you hadn’t guessed, the utilities are starting to recruit marketing managers from the telecoms industry.)  Whether or not you believe in that vision, it’s only going to start to become a reality when the industry decides on a wireless standard that spans phones, TVs and dishwashers.  There is a school of thought which believes that we’ll buy gateways that will translate between all of the different wireless protocols.  I don’t buy that one.  I’ve heard it before, as a solution to bridge between different combinations of Bluetooth, Wi-Fi, ZigBee, DECT, Insteon, X-10 and IrDA.  These gateways exist, but they’re expensive and complex to use.   I see nothing that will change that.

What the industry needs is a single standard to coalesce around.  That will drive volume, which will reduce price, which will increase its penetration from high end to standard appliances.  There’s lots of individual alliances and demonstrations going on, but they’re still at the stage of teenage groping, not meaningful, long-term relationships.  It doesn’t help that Government sponsored bodies, such as NIST and the EU are trying to impose their own agendas, like prudish parents who are attempting to enforce an arranged marriage.

Today the assumption is that home automation will follow the lead of smart meter deployments, as these will be the primary source of consumption data.  However, that may not be a valid assumption.  The utility industry has its own, peculiarly slow deployment timescales and a risk aversion that means it will probably fight to retain control of data.  Each utility or national Government may well mandate their own choice of wireless standard.  But by the time it’s deployed, the consumer industry may have gone down a different route.  Nest Labs has just launched its Wi-Fi thermostat.  It’s not the first, but the company’s founders have learnt lessons from their time at Apple about how to make a product desirable.  It’s certainly going to raise the barrier for home HVAC products.

But back to Amsterdam.  One of the most bizarre aspects was the closing session of the Smart Homes conference, which saw a panel session that crammed the stage with representatives of most of the competing standards.  The ZigBee Alliance was there, along with HomePlug Power Alliance, the KNX Association, Ultra Low Energy DECT, the OSGI Alliance, EnOcean, the Home Gateway Initiative and Z-Wave.  All was sweetness and light as they agreed that there was room for all of them to work together.  But you got the distinct feeling that you were looking at animals at the Zoo who were waiting for night to fall, each in the knowledge that their keepers had forgotten to lock the cages.  And each of them knew that as soon as the lights went out, one or more of them would be on the menu.

One of the speakers before me was Aidan O’Neill of PrePayPower in Ireland.  Aidan made a statement that the bulk of his customers spend more each day on cigarettes than they do on electricity.  It’s one of those throw-away lines that doesn’t really impinge at the time. Let me explain why it’s so important.

The energy industry has a mission to change consumer behaviour in the way we use energy, particularly at peak times.  They’re convinced that they can achieve this by introducing new tariffs - what they call Time of Use (ToU) pricing.  They consistently claim that users will “follow” the dollar”; in other words, if electricity is made more expensive at times of peak demand, millions of us will change how and when we use our appliances.  I’d argue that there’s precious little evidence for that.  Most people still need to cook meals and wash clothes at peak times and it will take a very big price hike to change that.

There’s lots of evidence that people won’t change, unless price increases are truly draconian.  When gas (petroleum) prices rocketed in the U.S. the higher cost didn’t spawn a new industry making more efficient cars.  Instead it signalled the explosive growth of the Hummer and the lookalike SUVs that guzzled gas as if it came out of the pumps for free.

The hard fact that everyone needs to acknowledge is that we spend money on things we like, whether or not we need them, or whether they’re good for us or our environment.  Governments have tried hard to control this addictive behaviour, slapping taxes on alcohol and cigarettes.  On one level they claim that this is to curb consumption and modify public behaviour.  On the other hand, they find it quite a useful source of revenue.

That latter point, the chance to demand more money from the consumer, is probably what makes Time of Use pricing look so attractive to utilities.  Smart metering and the promotion of energy saving is not really a very convincing business model for a utility, as it reduces its income.  There are lots of expensive consultants who will explain that this is balanced by savings gained from reducing the need to build new power stations, being able to optimise the grid and so on.  However, many of these arguments seem at best to be either self-serving or somewhat tenuous.

But if you’re a utility, it must feel great sitting in a focus group with consumers, asking them whether they’d support Time of Use pricing and appealing to their green instincts, persuading them that by doing so they’ll help to save the world.  Stephen Sondheim summed it up rather well with his words from “Into the Woods” when the Wolf meets Red Riding Hood for the first time:  “There’s no possible way to describe how you feel, when you’re talking to your meal.”  Why wouldn’t a utility love Time of Use pricing?  The question is: “will it really work?”

The problem is that for most people, energy use is an addiction, just like drink, alcohol, or any other drug of choice.  And like all drugs it’s incredibly difficult to wean people off it.  It’s not easy to change addictive behaviour.  The only area of addiction where Western governments have had any real impact is smoking, which illustrates just how difficult the job is.

As a population, very few people stopped smoking because they worried about its dangers, however graphically they were portrayed.  So a simple message that excessive energy use is bad for the world is unlikely to have much effect.  We could start with mandatory Government health warnings on light switches and pictures of dying polar bears on fridges, but my guess is that they won’t do much to change or shift energy demand.

Nor did people give up smoking when taxes were increased.  They moaned.  A few people went down the micro-generation route of growing their own, but most paid up and continued to puff away.

It was only when the message started to permeate that it was anti-social that behaviour started to change.  Legal judgements on the dangers of passive smoking started to change the moral ground, from where it became acceptable to castigate people about their habit in public.

That was reinforced by pressure groups taking tobacco companies to court over their marketing practices and winning massive settlements from them.  Only then did Governments act by banning smoking in public places, throwing more grist to the mill of ostracising smokers and reinforcing consumer behavioural change.  Yet despite all of this, many still smoke - they just do it in private.

Can we effect a similar social tsunami in terms of energy usage?  At what point will it be acceptable to publicly criticise a neighbour because they have an illuminated Santa on their roof at Christmas?  Or cook real food in their oven instead of microwaving a ready-meal?  And if we go down that route, what secrets might we find lurking in the vaults of our utilities that could set them up for public vilification and the chance to become the next Philip Morris?  Heaven forbid that at some point in their murky past they might have encouraged consumers to use more energy…

The prospect of becoming the next punchbag for the righteous consumer movement isn’t the only concern for the energy utilities.  They’ve probably not even thought about that possibility.  There’s a more worrying possibility that they should be considering.  Governments have seen acceptable or necessary addictions as a source of tax revenue in the past, and there’s no reason they couldn’t do the same again - this time with energy.  Instead of letting utilities profit from Time of Use prices, they could legislate to implement them as a Tax on Use, diverting the potential spoils from the utilities’ coffers to their own.  If they seize that opportunity they probably won’t even bother to pretend they’re trying to change consumer behaviour - they’ll just take the money.

Which brings me back to Aidan’s quote.  And here’s the insight I promised.  For all of the progress in changing society’s attitude towards smoking, PrePayPower’s customers still spend more each day on cigarettes than they do on power.  Yet these are the same customers that utilities believe will change their energy use as a result of the introduction of Time of Use tariffs.  If every stick and carrot that has been applied to get smokers to change their behaviour over the last fifty yeas has failed to have an effect on PrePayPower’s customers, what hope is there for Time of Use pricing?

Does anyone in the industry seriously believe that ToU will work?  Unless their wolf eyes can see a truth that the rest of us are blind to, then PrePayPower’s message is telling us that all the utilities can do is dream and drool.  Their Little Red Riding Hood won’t even acknowledge the Wolf’s presence as she sneaks a cigarette out of Granny’s basket on the way to deliver her daily packs of Woodbines.

There is no lack of agreement about the need to improve the grid and the way that we consume energy.  Growing demand, political concern over the stability of supplies, climate change worries, new challenges in the form of electric vehicles and decades of underinvestment in generating capacity and the grid have persuaded Governments around the world to support and mandate investment in new “smart” technology from smart meters in homes to intelligence in the grid.  The last time the world saw a similar level of stimulus was in the 1930s, during the great depression.  So this really is likely to be a once in a lifetime event.  The political will is there, the question is who decides how it is going to be done?  Groups like NIST in the US are pushing hard to put things in place, but are groups like this too academic in their approach?  Over the last year they’ve set up eighteen Priority Action Plans or PAPs to oversee development.  (A potentially unfortunate acronym as my dictionary defines pap as “worthless or oversimplified ideas”).  And according to a recent pronouncement they obviously don’t think the industry is doing enough to meet the challenge.  But before we look at that, let me share a quote with you:

“I hate those guys.  I hate those legislators and politicians - not because they restrict business and screw up the markets, even though they do and it does.  I hate governments because I know those guys.  I went to school with them.  And let me tell you, the weakest, most ignorant, most drunken incompetents work for the US government. And the bottom of the barrel, know-nothing dicks design the regulations for a market they know nothing about.  Why should we look at the regulations they’ve put in place by committee and go “Yeah, you suck at your jobs, fine, we’ll ignore that and suck at ours too?”

Not my words, but those of Lucy Prebble from her brilliant play “Enron“.  It’s a diatribe that she gives to Jeffrey Skilling - Enron’s President, as his empire starts to crumble.  Strangely, from a character that has little to commend himself throughout the rest of the play, it’s a dramatic moment where you suddenly start to feel sympathy with him, particularly if you’ve ever worked in a regulated industry.  Of course, that speech is just fiction and has nothing to do with the current situation…

The current spat is about whether to mandate IP over the entirety of the smart grid.  (IP as in Internet Protocol, not Intellectual Property, although the legislators ought to be a bit more aware of some of the implications of the latter than they appear to be.)  IP is the foundation of the Internet as we know it today and is generally a good thing, as long as you aren’t limited by power consumption or spectral bandwidth.  Or to put it another way, it’s fine as long as you’ve got a cable and a power supply.  It’s an obvious choice for most of the grid infrastructure and connectivity down to each house, but when you get to individual, battery powered devices within the home it start to become less than ideal.  I’ve written abut the reasons for this before, so won’t rehash them here.  Except to reiterate the fact that we need more experts from the embedded world to get involved in this debate.

This is all getting acrimonious because smart meters which are currently being deployed don’t use IP.  They mostly use ZigBee Smart Energy Profile 1.0, which uses an optimised protocol that was designed for low power wireless communications.  And they work well.  The only limitation is that they need a gateway device to convert the ZigBee protocol to IP when they want to communicate with the outside world over the Internet.  But that’s not a problem, as they’re always going to need a gateway because ZigBee in any incarnation is only designed to have a range that’s largely limited to the home.

The IP lobby, which is almost religiously fundamentalist in their views, don’t like this.  They want the smart metering world to convert to IP as potentially promised in the ZigBee Smart Energy Profile 2.0 as soon as possible.  Preferably yesterday.  And last week they formed a new PAP group - PAP18 - the nineteenth one, whose mandate is essentially to tell ZigBee what to do about making the transition from SEP1.0 to SEP2.0 painless.

The timing was interesting.  A few days before there was a schism within the ZigBee Alliance, where it has been reported that the working groups failed to approve the decision to use IP as a transport within Smart Energy Profile 2.0.  The deliberations of the working groups are confidential, but elements of that debate have been reported by EE Times and Smart Grid Today.  In the light of this, the NIST decision appears to be an attempt to exert pressure on the ZigBee Alliance to conform to their crusade for IP.

The ZigBee Alliance, like other similar industry groups, develops its standards through a process of consensus.  That bestows a couple of very valuable advantages:  it means that the standards process is less influenced by vested interests and it also gives the standard time to develop through debate, both of which are a good way of getting a better standard.  Each person eligible to vote will have their own reasons for accepting or rejecting a proposal, and those reasons are private.  But I suspect that one of the reasons for the recent rejection has been a reaction to the level of external pressure which has been applied to the membership.  That will be further informed by a different level of technical understanding of what is being asked, as within the ZigBee working group there are far more members who understand the implications and potential folly of forcing IP into small, battery power devices.  ZigBee is not alone in this tackling this dilemma - other low power wireless groups are having the same debate over taking IP to resource constrained devices.  There is not an easy answer, which is why this debate needs time, whatever wireless technology is being considered.

It is important not to be deflected by these current squabbles, and to understand that the industry does not need IP to connect to each individual device.  We do not need to make this decision now.  Smart meter manufacturers and utilities in regions that are leading deployment are working on a roadmap for the SEP 1.0 standard.  SEP 1.1 is already being tested by multiple manufacturers prior to formal certification and working groups are adding new functionality into a future SEP 1.2.  There is a valid roadmap for SEP 1.x that has no need of IP, as long as a gateway is installed in the home, which is what is happening.

There has been immense pressure to include IP.  The effect of that pressure, largely from NIST within the US has been the recent setback in ZigBee Alliance voting.  At best it will reduce confidence amongst those utilities embarking on their smart metering strategies.  At worst it will add a year or more of delays while they wait to see what happens?  For those utilities who have chosen to take the SEP 1.x route this isn’t a problem - they can just carry on with what they’re doing. However, those who believed the roadmap for SEP 2.0 and decided to wait for it may find themselves waiting a lot, lot longer.

I’ll stress again, whether or not we take IP to meters and IHDs within the home is irrelevant.  It is perfectly possible to access them using the non-IP approach of ZigBee SEP 1.0. Which takes me back to those words penned by Lucy Prebble in “Enron”.  If you get a chance to see the play, it is well worth it.  If not, go out and buy a copy and read it.  You’ll have plenty of reading time while you wait to find out what SEP 2.0 will be.  And if you know someone in NIST, lend them your copy when you’ve finished.

The whole concept of bringing Internet Protocol to battery powered devices in this new era of the Internet of Things is not confined to smart metering - it’s a question that is being wrestled with by many standards groups who are trying to balance issues of accessibility, interoperability and power consumption.  In general, the closer a product is to commercial deployment, the less sway the IP proponents have.  But they have the US power industry in their sights.

I don’t believe that their arguments add up.  If smart metering is to work it needs to look at the whole picture and make pragmatic decisions.  The UK approach seems far more sensible, which may be why it’s making far better progress.  In contrast, there’s a distinct feeling of banana skin about the IP advocates and their promotion of ZigBee Smart Energy Profile 2.0.  As time goes on it looks like an approach that is having to conceal more and more inconvenient truths behind a veil of smoke and mirrors.

The argument has nothing to do with the potential benefits of smart metering (albeit they still need to be proven), or the basics of ZigBee’s Smart Energy Profile.  Most in the industry would agree that they are the only way to go for smart metering at the moment.  The question is how to address smart meters and individual devices that are connected to it over the Home Area Network?  There are two schools of thought.  Those using Version 1.0 of the Smart Energy Profile typically connect to meters via a gateway device which is located on the Internet.  This means that the gateway has an IP address, so that it can be found by other internet devices.  The smart meter and other devices in the home don’t have their own individual IP addresses.  Instead they can be accessed via the gateway, which knows what they are, and can direct messages to them.  That’s the same way most people are accessed.  The gateway is like our home or office, which has a unique address, and we have our individual names so that we can be located at these addresses.  The important point to recognise is that our names aren’t normally unique.

The IP advocates claim that this is not good enough and that every device should have its own individual, unique 128 bit IPv6 address.  (Intriguingly, I don’t know any of these advocates who have changed their personal names to a unique 128 bit address, so their IP preaching has a slight ring of “don’t do as I do, do as I say”.)

On the surface this makes some kind of sense.  But when you start looking at what needs to be done to make a truly low power wireless device that logic starts to peel away.

When you design a battery powered wireless product you put a lot of thought into how to make the battery last as long as possible, especially if needs to have an extended battery life.  There are a number of techniques to achieve this.  You want the device to stay asleep, consuming minimal power for as much of its life as possible.  When it does wake up to send something you want it to be awake and powering the radio for as short a time as possible, and to be able to go back to sleep again as quickly as possible.  It doesn’t matter what wireless standard you’re using - these are universal principles.

To minimise the time they are on, low power wireless protocols are designed to use very short packets of information, which can be sent very quickly.  ZigBee has a maximum packet size of 127 bytes.  Bluetooth low energy is even more frugal at just 47.  Each packet needs to contain a destination and source address, which is a necessary overhead for any wireless protocol.  With IPv6 (which is what the IP lobby wants to use to accommodate all of the anticipated devices), that takes up a minimum of 32 bytes.  In many cases it takes double that.  In contrast the data being sent in the same packet usually requires only a few bytes.  Which means supporting an IP address on these devices may increase the packet length by an order of magnitude.

A useful analogy is to look at packing in the supermarket.  An efficient radio protocol is like a banana - it comes ready packaged.  If we were just to add an old IPv4 address it would be like wrapping it in cellophane.  IPv6 adds a presentation box, a bow and a carrier bag to take it home in.  In the eyes of a low power designer, it’s the wireless equivalent of landfill.

Everybody who works with IP it knows it’s bloated.  That’s not a problem for products that use cables and have power supplies, but it’s anathema for low power wireless devices.  Recognition of the bloat is why we have 6LoWPAN, which is an attempt to shave the problem down from supersized to merely clinically obese.  But it’s still too big.  Yet this is what the ZigBee SEP 2.0 proponents are clamouring for.

It’s not the only problem with taking IP to a low power wireless device.  The TCP or UDP protocols above it are not designed for link layer acknowledgments.  As I indicated above, efficient low power wireless devices want to transmit the minimum amount of data as quickly as possible and then go back to sleep.  But most want an acknowledgement that the data was received before they go back to sleep.  That’s most efficient when it can happen low down in the protocol stack, which is what happens with well designed radio protocols.  Add TCP or UDP and the acknowledgments happen higher up the stack, which means the radio has to stay awake longer before it gets the acknowledgment back and can turn off.  This highlights the major difference between radio protocol designers and the IP protagonists.  Efficient radio protocols are designed from the bottom up.  In contrast the IP zealots are trying to impose their view from the top down.  And that doesn’t lead to an efficient radio.

Which brings us back to the UK - US divide.  Both countries started with the same Zigbee SEP 1.0 standard.  In the US, NIST, who became involved in the smart energy standards, decreed that IPv6 must be supported by every device, so the whole industry upped stumps and started developing SEP 2.0, which will include 6LoWPAN.  In contrast the UK evolved the standard to SEP 1.1.  Having completed that, they’re moving on to enhance it with SEP 1.2.  And there’s already talk of an SEP 1.3.  Most of Europe is following the UK lead - it’s pragmatic and it’s working.  The industry is working to add features to the 1.x SEP standards that are relevant to the evolution of smart metering, not engaging in an orgy of technical masturbation.

While the SEP 1.x activity is moving steadily forwards, the SEP 2.0 efforts continue to slip.  Despite the issues, the believers are still worshipping their sandals and gourds and brandishing the scourges to drive their followers faster. In a move reminiscent of Napoleon in George Orwell’s Animal Farm, NIST recently published an edict for the loyal congregation to work harder to finish the great task before them.  It is frighteningly evangelical in its approach.  And in pushing its vision, it’s promoting another rather inconvenient truth.  Which is that the route between the two visions may be illusory.

The fact that is rarely spoken is that an SEP 1.x device cannot talk to an SEP 2.0 device.  That’s because of the simple reason that they use different networking layers.  One uses IP and the other does not.  That worried many utilities who wanted to start their deployments with SEP 1.0, as SEP 2.0 is still a fair way out into the future.  They didn’t want to install meters which would end up as stranded assets.  So in SEP 1.1, the ZigBee Alliance added an “Over The Air” Upgrade cluster.  This allows new firmware to be propagated down through a mesh of SEP 1.1 or higher devices, which, once installed will upgrade themselves to support SEP 2.0.  (I personally think there are some interesting topological inconsistencies with this theory, but that’s another story.)

What we’re now seeing is that the SEP 2.0 firmware is growing.  It looks as if it is growing to such a size that most of the chips in current 1.0 and 1.1 devices will not have the resources to store and run the new 2.0 firmware that they receive.  So the industry is selling a story and convincing itself of the efficacy of an upgrade that is unlikely to work.  We don’t yet know the extent of that problem, but it probably means that many utilities that had planned to migrate from 1.1 to 2.0 may discover that their only option, once they have installed a 1.1 meter is to upgrade it and all of the associated devices around it, to 1.x.

The bigger stack also means that we’ll need more processor power and more memory, so implementations will be more expensive.  And reports are starting to come in that, with the bigger stack, power consumption in early test devices is significantly higher than had been forecast and a lot more than SEP 1.x.   That’s a major concern for battery powered devices like IHDs and gas meters, as they may not be able to support SEP 2.0.  For consumers it means they’ll either have to waste power by plugging their IHD into the mains, or work their way through a mountain of batteries, neither of which are very true to the spirit of saving energy.

The main reason that the UK has not gone down this route is because it’s included the energy industry in making the important decisions about the technology.  In the US, the industry has been led by technology startups and standards bodies, who have other agendas.  Some of them are already exhibiting their normal attention span deficit and suggesting we need a Smart Energy Profile 2.1, which uses CoAP on top of 6LoWPAN.  That’s moving the protocol goalposts rather than refining the features, and has the potential to add another chapter of confusion and interoperability issues.

It places the US smart metering community in an “Alice through the Looking Glass” world of always waiting for jam tomorrow.  With stimulus finding dwindling and VC interest waning, there’s a good argument that it would make better sense to step back and consider what it really wants?  To follow the pragmatic approach from the UK, or continue living on promises?

++++++++

A week after writing this, there was a vote within the ZigBee Alliance which appears to show that I am not alone in having these doubts.  This is covered by Rick Merritt of EE Times in his report that “Vote delays smart grid software”.

It’s a nice high-tech story, but does it make sense?  You can see how it has evolved from the effort that is being put into smart grids.  The theory is that to reduce the strain on generating capacity, it makes sense for energy hungry appliances in the home to adjust their start time, so that they run when there’s least demand for electricity.  Hence by connecting appliances within the home to your smart meter, or your utility’s web site, they can be told when to turn on or off.  Which, on the surface, makes a certain degree of sense.

But there’s another side to the story.  The connected appliance doesn’t save energy - it just means that it uses the same amount of energy at a different time. The other approach is to make the appliance more energy efficient.  When you look at the relative efficiencies of different products, the manufacturers who seem most enthusiastic about smart appliances are those who sell some of the least efficient ones.  It makes one wonder whether their interest in connectivity is just a PR sticking plaster to cover up their poor performance.  Instead of investing in research they see an easier win in investing in media techno-babble.

The problem with doing that is that the promotion of smart appliances ups the requirement specs for the smart meters and gateways that are at the core of home energy management.  Rather than let the smart metering industry have a period of relative stability to confirm their technical specifications, complete trials and educate users, this new mania around connected appliances adds a level of unnecessary technical uncertainty.  As such it is a very dangerous distraction to the core requirements of smart energy.

There will always be a group of techies who want to connect everything and automate their lives.  The smart grid projects happening across the world have given them a golden opportunity to claim that home automation is finally here.  They’ve been saying that for the last sixty years without any great success, but believe that with the advent of cheap wireless, ubiquitous smartphones, iPads on every wall, universal broadband access and billions of Obama stimulus dollars flooding into their tech start-ups, there’s nothing to stop it happening in the next year.  (The fact they believe that everyone else owns and uses all of these devices does provide a good indication of their limited grasp of how most of the world really lives.)

As I said above, one of the goals of smart energy is to smooth out demand for electricity.  That helps utilities and generators to manage the distribution network more efficiently and helps them plan when they need to build new power stations.  Already in some parts of the world, utilities offer load shedding plans to consumers, which allows the utility to turn off domestic air conditioning units for short periods when there is peak demand, in exchange for lower electricity tariffs.

The smart appliance promoters believe that this principle can be applied to other energy hungry device around the home, such as fridges, freezers, washing machines and dishwashers.  At CES, LG even suggested that a smart oven could cook your meal more slowly if it noticed that electricity demand was high.  Which would give kids an excellent excuse for being late for school - “Sorry Sir, my toaster was experiencing peak demand, which meant my Pop-Tarts were an hour late.  But it helped me save the world.”

This all relies on the consumer wanting to save money, or in a few altruistic cases, wanting to help the environment.  It requires them to be prepared to inconvenience themselves by putting aside their “I want it and I want it now” mentality and accepting that the washing may not get done for another few hours.  As experience shows that not many consumers act this way, the proposed stick to change their behaviour is to vary electricity pricing on an hour by hour basis so that using your washing machine at peak times will cost more.  Hence the drive to add connectivity to appliances, so that they will know how much it costs to run at any particular point in time.

There are a couple of issues with that.  The first is that many users may not have the flexibility to shift the time they do their washing.  Parents with children need to wash their clothes in time for them to go to ballet lessons or play football, which means they may have very little choice - the washing goes in when it appears.  Even if they did have that choice, very few utilities will have the ability to move to this type of granular tariff in the short to medium term.  In order not to be divisive, they need to offer these new money saving tariffs to all of their customers, which means installing a lot of new smart meters.  That’s already underway, but the world needs to update 1.6 billion electricity meters.  That’s started and it’s a work in progress, but it is unlikely to be completed before 2020, so widespread availability of Time of Use pricing probably won’t happen for at least the next five years.

Behind that reality, the driving forces that are talking up smart appliances are the wireless standards.  All of them - ZigBee, Wi-Fi, Bluetooth and 3G want to conquer the world and are desperate to find a market which will provide another billion chip sales every year.  They’ve all been working hard on the smart metering opportunity, but have seen that go into a lull, as utilities wait for feedback on the first tranche of deployments.  Only then are the utilities likely to sign off the national and regional specifications for the major roll-outs which will commence a few years later.  Which leaves the wireless companies with something of a quandary over what to do for the next few years?  So, according to the old adage that “the devil will find work for idle hands to do”, they’ve turned their attention to extending smart energy connectivity to encompass everything they can find within the home.  For each of them, the smart appliance is their current wet dream, with its prospect of billions of connected devices.

It’s a message that is resonating within certain elements of the white goods industry who want to smarten up their energy saving credentials.  By buying into the connected appliance story, they’re able to get on the bandwagon of claiming to be energy conscious.  The question is whether that’s driven by cynicism.  In an earlier piece I looked at the energy efficiency of GE appliances and found they were less than wonderful.  After the media frenzy at CES I was prompted to look a little more deeply and see how well others promoting this idea are doing.

Once again I turned to two sites which list the performance of domestic appliances in the US - the Energy Bible for dishwashers and washing machines and the Government’s Energy Star site for freezers and refrigerators.   The first gives an Energy Factor value - the higher the number, the better the device.  In contrast, for freezers and fridges, the number given is the energy consumption in kWHr per year, so in this case we’re aiming for lower numbers.

In the case of washing machine and dishwashers, GE and Whirlpool, who have been staunch advocates of connected devices fare very poorly.  For refrigeration, they’re better, but still not at the top of the list.  These figures take the average of all the machines for each vendor in the published lists.  If you look in more detail at the source information, the cheaper appliances from most manufacturers generally perform significantly worse.  Now, think about the demographic of owners.  There’s probably a good correlation between the people with the least ability to use their appliances outside peak times and these cheaper, poorer performing machines.  This means that any improvement in reducing grid load by using smart appliances is likely to come from a limited portion of the population.  So if these companies really want to help the grid, they should be concentrating on improving product performance, not fobbing users off with the story of smart appliances.  To my mind a smart appliance should be smart and efficient autonomously, and not rely on an internet connection. 

Fridges and freezers seem even less suited to being smart, as they are on 24 hours a day, so the emphasis must be on making them still more efficient in their own right. The industry has come a long way in the last decade, cutting consumption by 2 to 3 times, mainly by improving insulation.  But there is still new technology to be explored.  As an example, take True Energy, a company based in the UK, which has recently announced their SureChill technology.  It’s been designed for vaccine storage and uses phase-change materials to maintain temperature in a fridge in the absence of power.  This gives it the potential to keep a fridge cold for periods without power, decreasing the electricity consumption.  It seems a far better approach to reducing demand on the grid than adding connectivity and complexity, and I’d far rather see the industry concentrating its attention on technology like this.  I suspect there is plenty of scope for improvement without the need for wireless.

As I said at the start, this new concentration on smart appliances is a dangerous distraction for the smart energy industry.  It adds technical uncertainty at a point when the industry is trying to coalesce on standards for smart meters and it distracts appliance vendors from concentrating on core improvements to the technology of their devices.  By offering the prospect of jam tomorrow it also distracts users from starting to understand their current energy usage.  Utilities are just beginning to provide energy meters to their customers, along with information on how to save energy users.  That’s a very important thing to get right.  If the media is promoting a story that smart appliances will solve the problem, much of the momentum may be lost.  And as appliances only get replaced every ten years or so, that could put back energy consumption by a decade.

These are important issues.  The industry needs to consider whether the prospect of a smart appliance is worth pursuing in the short term, as it has the potential to do more harm than good.  It’s time to think about whether it’s any more than a PR ruse, particularly given the performance of appliances from those who are so active in supporting it.

It was written to promote GE’s view on which wireless standard should be chosen for the Home Area Network (HAN).  These are designed to connect devices around the home to a smart meter or a home gateway that has access to information about your current energy tariffs.  GE thinks the best choice should be ZigBee because “ZigBee is better than Wi-Fi”.  One of the paper’s authors is an active editor for the ZigBee Alliance Smart Energy Profile, so that’s not surprising - he’s entitled to be enthusiastic about the technology he’s part of.  And it may be that ZigBee is a good choice.  But GE’s analysis doesn’t provide any evidence as to why it might be.  Instead it provides an evidence-free quasi-analysis that does ZigBee more harm than good.

We’ve had a year of hype as different wireless standards vie for the crown of being chosen as the de facto one for smart metering.  Much of that obscured the facts which need to be considered to make that choice.  In the last few months I thought the industry had settled down and was beginning to a bit more logical.  This rant from GE suggests that some of those involved in the debate still have a lot to learn.  If you want to see how not to make a reasoned argument, download and read the GE white paper.  I’ll highlight what is so wrong about it.

There is no shortage of wireless standards that would like to be picked.  The current runner setting the pace is ZigBee, but Wi-Fi and Bluetooth are there as well, plus a bunch of prominent also-rans, including Z-Wave, Wavenis and Wireless-MBUS, along with a clutch of rank outsiders.  Most of these standard would admit that they still have some way to go.  None of the standards are yet fully fit for purpose for smart energy, but most of them recognise their deficiencies and are working on fixing them.  There’s a valid argument that none are really good enough and the industry should take the best bits of each and come up with something new, but we probably no longer have time for that approach.

Because none of them are perfect, it’s proving difficult to make a choice, as government led groups around the world are discovering.  Many different factors need to be weighed up, of which the most important are range, power consumption, robustness to interference, security, interoperability and IP ownership.  Throughput and latency, which are important in other wireless applications aren’t particularly relevant for smart metering, as so little data is transferred, none of which is time critical.

In their white paper, GE is quite content to ignore robustness, security, interoperability and IP ownership, which makes the job a lot easier for them.  And they limit the contenders to Bluetooth, ZigBee and Wi-Fi.  So they’re making their task relatively easy by not being very representative.  Yet they still manage to mess it up.

They start their analysis with range.  Range is one of the most misunderstood parameters in wireless connectivity.   For any of the standards operating at 2.4GHz, if the radios are transmitting at the same power, with the same antenna, the range is predominantly determined by the receive sensitivity.  That depends on the ability of the receiver to extract a signal from the noise, which is a factor of the symbol rate (the rate at which you modulate the signal), how many symbols you use to encode each piece of data, and to a lesser degree the modulation method, modulation index, the degree of error correction used for the packets and the amount of receiver diversity you use.  For more about how these all work together, have a look at my book - “Essentials of Short Range Wireless“.

That’s obviously all a bit too complicated for the GE team.  Instead they make the observation that the Bluetooth range on their mobile phone is only a few metres.  On that basis, they discard it from further consideration.  There’s a reason the range is limited on most phone, which is because phone manufacturers understand power consumption.  For them, the most important parameter is battery life.  As most Bluetooth applications only need a range of a few metres - typically from the phone to a headset, they cut the transmit power down to minimise the power draw.  2.4GHz radios tend to be exponential in their power draw.  So a device transmitting at 4dBm will consume 30mA, whilst one transmitting at 14dBm will probably take up 250mA.  For a phone manufacturer, 30mA is acceptable, 250mA is not.  They do the same for Wi-Fi implementations, which is why your phone’s Wi-Fi range doesn’t match that of your laptop.  But I suspect the people writing this paper haven’t yet worked out how to use Wi-Fi on their phones. 

You can see that GE engineers might not appreciate this subtlety - after all, they’re not experts in power management, as their devices don’t have to run on batteries.  It’s ironic that the poor efficiency of household appliances is one of the reasons we need a smart grid in the first place.  If you have a look on the energy bible site for dishwashers, the best performing GE product comes in at position 147 out of 605.  And over half of their products fall into the 16% of worst performing dishwashers.  (I chose dishwashers as there’s less variation in size, so it seems a fair comparison.)  Hence GE can hardly claim to be qualified to pontificate about power consumption.  Although that doesn’t stop them.

That’s not the only deficiency this paper has.  They state that Bluetooth is based on the IEEE 802.15.1 standard.  It’s not.  Bluetooth writes its standards independently.  It contributed an early version to the IEEE, but that’s five versions out of date.  They also refer to the Bluetooth Alliance.  A quick check of the website, or any of the specifications, all of which are publicly available, would show them it’s the Bluetooth Special Interest Group.  There’s no such thing as the Bluetooth Alliance.  Maybe they’re confused because Alliance rhymes with Appliance.

But on with their range experiment, which is now down to deciding between ZigBee and Wi-Fi.  The first bad point they find against Wi-Fi is the fact that ZigBee “is the lowest power”.  Putting aside the fine detail that power consumption depends on topology and application, I’m afraid that’s not true either.   Like for like, Bluetooth low energy, Z-Wave and Wavenis are all lower power than ZigBee.  But they’ve already been excluded, so according to GE, they don’t count.

But then Wi-Fi stumbles again, because according to GE, ZigBee is the only standard that supports mesh and ZigBee is generally used in a mesh.  Unfortunately for GE’s analysis, ZigBee is not the only standard for mesh.  Mesh can be run over most networks.  There are plenty of commercial mesh networks running over Bluetooth.  And ZigBee isn’t the only wireless standard that has specified mesh.  There’s another one.  It’s called 802.11s, which is part of the 802.11 set of standards which underpin Wi-Fi.   In fact, most ZigBee implementations don’t use mesh.  The standard includes it, but the bulk of commercial deployments only use ZigBee in a star network or cluster tree topology.

Then comes the issue of cost. Apparently Wi-Fi chips are around $2 more expensive than ZigBee.  That will come as a shock to the companies who bought around 700 million Wi-Fi chips last year, a volume that helped drive the price down.  In contrast, less than 10 million ZigBee chips were sold, according to IMS, which means they’re typically more expensive than Wi-Fi.   And both are a lot more expensive than Bluetooth, which is now shipping for less than $1.

Now we get the really weird bit.  GE claims that an additional processor is needed to run the protocols for these chips and for Wi-Fi that costs $11 more than it does be for ZigBee.  My experience is that people using embedded Wi-Fi and Bluetooth are writing their application code directly on these chips.  After all, most of these chips already contain two or three processors.  So developers don’t need to use another separate microprocessor.  And certainly not one costing over $10.  So GE doesn’t seem to know how to design products cost effectively, and are using that inadequate engineering to try and tell the rest of the world what to do.  But maybe that’s why GE appliances cost so much. 

Having tried to bludgeon us into submission with a concerted display of ignorance, they now change tack to prove their point with an experiment.  They take a ZigBee chip (a good, low power one) and compare it with an 802.11n chip, which they claim is low power.  In one sense they’re right, the 802.11n chip they use is designed to be low power.  Or at least low power for 802.11n, which is capable of constantly pushing several hundred Mbps of data across a link.  If they had wanted to do a valid comparison, they should have chosen an 802.11 chip designed for low power sensor applications.  In other words, they should have used one operating at 1Mbps using DBPSK modulation, such as the ones from Gainspan and G2 Microsystems. 

Instead they perform a comparison of bicycles against jumbo jets and come to the surprising conclusion that bicycles are lower power.  Which means that in GE’s eyes, ZigBee wins.

In a final act of madness, they do a calculation of the savings that a customer would make if an appliance used ZigBee instead of Wi-Fi.  They don’t separate out the power taken by their unnecessary external microprocessor, (they never tell us what that is), so it’s all very dubious.  But they claim that choosing ZigBee rather than Wi-Fi would save a customer a massive 4.2 kWhr per appliance per year.

Let’s go back to those energy bible figures.  If you sort them by annual power usage, GE dishwashers take up 48 of the bottom 60 places in terms of energy guzzling consumption.  They consume around 324 kWhr per year, against the most efficient dishwasher on the list - the Fisher & Paykel DS605, which takes only 157 kWhr per year - less than half the power of the GE appliances.  So if they spent their time concentrating on designing decent appliances rather than writing silly papers like this, the GE team could save the user 167 kWhr per year, which makes pontificating about the choice of radio based on a 4.2 kWhr saving seem rather irrelevant.  If you’re beginning to think that GE engineers who live in glass houses shouldn’t throw stones, you’re probably right.

What is worrying is that this has been submitted to the study groups looking at wireless for smart grid as a serious paper.  Every proponent of a wireless standard will be biased to some degree - that’s to be expected, as you’d expect the people working on a standard to believe in it.  But this paper trivialises the whole process.  As I said, it ignores important points like robustness, IP, interoperability and security.  One of the most thorough analyses I’ve seen regarding these points is in a paper put out by the Bluetooth SIG, which is worth reading.  In comparison, this GE white paper is little more than an evidence-free rant.

I don’t think that this does the cause of Smart Energy any good.  Nor does it bring any honour to the ZigBee Alliance, who I suspect are embarrassed by it.  And it certainly does nothing to enhance anyone’s opinion of GE.  If this is the level of due diligence they apply to technology it’s no wonder their appliances sit at the bottom of the league tables for energy efficiency.  On the basis of this report I’ll keep on buying Fisher & Paykel and Zanussi.

To understand why equating a standard with interoperability is a fallacy, let’s start with an analogy.  In many ways, a standard is like a language.  So we could define English, or French or Russian as standards.  The standards bodies would then claim that everyone who speaks the same language is interoperable.  I’d disagree.  The language defines the grammar and the vocabulary, but you only have to listen to a Democrat and Republican senator debating health reforms to understand that speaking the same language does nothing to promote interoperability.  If anything, a standard provides the tools to ensure that conflict is more, rather than less likely to occur.

Interoperability is about working together seamlessly.  To achieve that requires more than just a standard.  It needs a set of interoperability tests and the testing tools to confirm compliance with those tests.  These don’t generally come with a standard - they need to be put in place to support it.  That entails time and money, which means most standards can’t support them until they’re already fairly well established.  Industries like Smart Energy demand interoperability, as they want the meters they install today to work with devices that customers may install in ten or twenty years’ time.  But if they want to achieve it, they, need to understand how this process works.

(You can download this article as a pdf - The Evolution of Interoperability. Making the Dream a Reality.)

Let’s start with a definition:  Interoperability in this context is the ability for any two devices to connect together and support a meaningful dialogue, regardless of who made them, how they’re used, or what else they may have connected to in the past.  It is the aspiration to that ideal state where there will be a flawless interaction between products created by different manufacturers. 

That’s not an easy definition to visualise.  Interoperability can be a difficult concept to grasp, especially for a wireless connection.  The primary reason for that is although wireless standards basically replace a cable, at the same time they offer the promise that once “connected”, widely different devices should be able to “communicate” with each other.  I use quote marks for both of those terms, as when you think about them, they’re far from obvious.  If you connect a weighing scale to a mobile phone, what should it do?  What does a connection between a smart meter and a washing machine mean?  Or one between a pair of running shoes and a headset?  At the highest level, interoperability has to rely on an application, which goes beyond the scope of wireless standards.  However, interoperability has become a desirable tick box in many industries, regardless of whether it makes any sense.

To explore what wireless interoperability means, let’s start with the simplest wireless scenario of a broadcast service.  A good example is a television, where programs are transmitted in a defined format by a few large broadcasters to a range of passive receiving devices called TVs.  The way in which the programs are broadcast is determined by a number of different standards - typically NTSC, PAL or SECAM.  Because broadcasts are normally confined to national boundaries, there’s not an obvious interoperability problem.  However, those different standards meant that TV manufacturers used to have to make different, incompatible models for different countries.  After thirty years of relative stability, newer HD formats have arrived which are not compatible - it you have an old TV you can’t display them.  Nor is there any way you can upgrade your TV to an HD format.  Which highlights two points: which are that both ends of the wireless link need to support the same standard if you’re going to get interoperability, and that interoperability is not the same as, nor does it confer backwards compatibility.

For broadcast TV, interoperability is relatively easy, as a very few companies control the broadcasts, and as soon as you turn on you TV it receives the signal.  It does not need to connect, or pair, or negotiate encryption keys.  It’s an embedded device that has been designed to do one thing. The next level of complexity is where devices can have a two-way conversation, transmitting as well as receiving.  That means they need to connect and establish a link between each other.

An everyday example of this is a mobile phone and the cellular network.  This is a simpler interoperability problem that it might first appear, because phones do not connect directly to each other.  Instead each connects with the network infrastructure, which transfers the data between the two (or more) appropriate handsets.  Handsets and base stations have to conform to industry standards.  For most phones those are defined by ETSI - the European Telecoms Standards Institute, which is responsible for the GSM and 3G standards which are widely used.  It’s not the only standard, but it accounts for over 4 billion connections throughout the world.

Despite those numbers, there are not that many different mobile phones, and even fewer different base stations that they connect to, because the industry is controlled by a relatively small number of companies.  One of the reasons for the small number of companies is the cost of implementing the standards, plus the cost of testing them.  Before a mobile phone is brought to market it needs to pass a stringent set of qualification tests, which can cost anything up to $1,000,000.  At that point it becomes legal to sell it.  However, before a network operator will sell it to you, they insist on it passing a further set of interoperability tests.  In Europe that’s the GCF test schedule; in the US it’s the PTRCB, both of which are of similar complexity.  These extend the normal tests to check that the phones correctly implement the features that are critical for working on real networks.  Both of these provide significant barriers to entry for new companies, but between them they provide a high level of assurance for users and operators that phones will work.  That’s very important for network operators, because if phones don’t work, then they won’t make any revenue from calls.  Yet despite that, most users have experienced calls failing to connect, or had issues in sending pictures between different networks.  And that’s despite the fact that there’s a limited number of players, that phones can only connect to a limited number of different base stations and that every product that gets to market is extensively and expensively tested.

Which brings us on to short range wireless.  It doesn’t matter which standard it is - they all have the same issues.  Users expect a wide number of products to be able to connect to each other, for them to work out what they can do and then share information with each other, whether that’s a piece of data like room temperature, a voice stream, a data file or a video.  Interoperability is the expectation.  Regardless of who makes an individual device, users believe that it should connect to any other device which supports the same wireless standard, within the bounds of what is reasonable expectation (and I still don’t expect a pair of running shoes to talk to my Bluetooth headset, but one day someone will).

Specification writers try hard to make sure that their standard supports interoperability.  That means they need to define how devices connect, what protocols they use to transfer data between each other, how that data is formatted and how to recover if things go wrong.  Defining that for a wide range of applications is difficult, which is why most wireless specifications are several thousand pages thick.  The problem is that this level of complexity invariably means that different implementers take slightly different approaches, and because they’re human, make slightly different mistakes.  Out of 2,000 pages, it only needs two developers to interpret one line of that specification differently and you have an interoperability problem.  That’s the main reason that devices don’t always work with each other in the way we expect.

That’s the reason we have problem.  What is counterintuitive about interoperability is that it changes during the life of a standard.  In the early days of a standard there are very few products on the market.  Generally they’re being produced by the companies that have dedicated resources to writing the standards, so they’re keen to make sure that these first products are interoperable.  (That’s just good vested interest.  If they’re not, the negative publicity doesn’t attract other companies to use the standard, and consumers are put off buying it.)  To ensure interoperability, these manufacturers will test their products with each other, making any modifications necessary to demonstrate interoperability. The important point to note here is that these modifications may not make the products comply with the standard.  They are fixes to solve problems, and as such may perpetuate deviations from the core standard.  These will probably be ignored if everything works, as without a test system that checks compliance to a standard, expedience tends to win.

As the number of products starts to grow, the task of testing everything against everything else becomes impossible, as it grows factorially.  Major manufacturers will still perform extensive testing of their flagship products, but in general interoperability starts to take a nosedive.  The other thing that happens is that as more and more manufacturers start to write protocol stacks and profiles, each tends to deviate slightly from the standard, because of minor differences in interpretation and implementation.  Rather than testing these rigorously against the specification, effort tends to be put into ensuring interoperability with what each manufacturer sees as the market leading product.  That results in more patches to make their stack work.  If in turn they become successful, other manufacturers will do the same thing against that product, running the risk that de facto implementations start to
diverge from the specification.

As more and more products and manufacturers come to market, this leads to sets of products that work with others in their group, but which exhibit a steadily decreasing level of general interoperability against the standard.

Many standards attempt to address this by designating a small number of “golden units”.  These are products that are meant to be the best case implementations, and which act as a reference against which other products should be tested.  There’s generally strong competition between manufacturers for their products to be chosen as golden units.  That can be counter-productive, as it results in a rush to generate products early in the life of the specification, when they are likely to have had very limited testing. 

It also leads to another problem, which is the issue of waivers.  If a product fails to interoperate with a golden unit, but the manufacturer believes that their product conforms to the standard, they may ask for a waiver.  In theory this should lead to the golden unit being updated.  Far too often it results in a growing grey area around the golden units, where once again market practice diverges from the word and intent of the specification.  It’s not uncommon with the golden unit approach to find two products that comply with the standard, but which cannot talk to each other, or two products that are interoperable, but where neither conforms to the standard.  There have also been examples of two golden units from different manufacturers that are incapable of working with each other, but which are still considered acceptable for testing.

The solution is for a standards organisation to invest in automated interoperability testing equipment which is designed to test every product against the specification.  It’s not an easy option to choose.  The Bluetooth SIG made that choice in 2005, when they saw a growing number of interoperability issues.  The result was their Profile Tuning Suite (PTS) - an automated piece of testing software that runs on Windows, and which can be used to test (and help develop) new Bluetooth products. Because it tests products directly against the specification there should be no question of deviation.  If a manufacturer thinks there is a problem, then that can be checked against the standard, and the PTS updated to correct an error, or an errata can be raised to clarify the specification itself.  It provides a closed loop system that helps to ensure that all new products move closer to the standard, rather than drifting away.

It’s not a trivial decision to develop this type of software.  Over five years, it has cost the Bluetooth SIG around $10 million to develop it to the level at which it operates today.  That cost doesn’t diminish with time, as there is an ongoing expense to maintain and update it, as well as extending it to cover new releases of the Bluetooth specifications.  Nor is $10 million the whole cost to date - member companies and test houses have probably contributed an even greater amount in terms of engineering resource that they have provided.  But the results are dramatic.  Since it’s been in place, it has been used to test over 8,000 products and has resulted in a significant improvement in interoperability, as indicated by the diagram.

No other short range wireless standard has even started down this route.  That means that Bluetooth (and Bluetooth low energy, which uses the same tester) have a five year lead over other short range standards like ZigBee and Wi-Fi in terms of being able to guarantee interoperability.

When initiatives like Smart Energy talk about interoperability they need to understand this distinction.  A standard does not confer interoperability.  In a mass market, interoperability can only be achieved by stringent testing against the specification itself.  For that you need a test system, backed up with an enforcement policy that can remove non-compliant products from the market.  Unless an organisation has already embarked upon putting those into place, it will take them around five years before they can even start to claim that they have a handle on interoperability.  Interoperability does not have short cuts. 

In conclusion, if you need interoperability, make sure you’re asking the right question.  Slick PR from a standards body is no substitute for doing it properly.  If a standard tells you it’s interoperable, don’t believe them until they show you their interoperability test system and enforcement program.  If they can’t, it’s likely that they’ll follow the curve of increasing interoperability problems and growing customer disenchantment.

(You can download this article as a pdf - The Evolution of Interoperability. Making the Dream a Reality.)

Whilst some of these approaches consider cost in terms of the price of silicon, or even the opportunity cost in terms of time to market, one significant cost has been missing from their calculations - the cost of choosing a standard that opens up Intellectual Property disputes.  That’s a real risk.  The only place I’ve seen it publicly stated is in a briefing document from the Bluetooth SIG, which points out that from the IP viewpoint, wireless standards are far from equal.  It’s a very valid concern.  We’re already seeing the patent trolls coming out and attacking ZigBee and Wi-Fi.  As volumes start to increase, so will their determination to make a fast buck.  As soon as that happens, deployment could grind to a halt.

Intellectual Property Rights in standards is something that most people ignore.  There’s an assumption that if a standard exists, then as long as you acquire the right to use it, there are no IP issues.  Unfortunately that’s not true.  A lot of companies have been taken to court for that misplaced belief, and ended up paying millions of dollars, or in extreme cases, going to the wall.  So it’s important to understand the IPR landscape with respect to standards.  I’ll start with the same statement that’s in my book:

The existence of a standard does not give a company a free right to exploit it, nor automatic access to the IP within it.  To use it you must agree to the terms of the body which owns the standard.

These terms vary, but if we look at ZigBee and Bluetooth, each requires a company that uses the standard in their product to sign a member agreement which contains a clause of IP ownership.  You can read the Bluetooth one here and the ZigBee on in Annex 2 of their agreement.  Both introduce the concept of Necessary Claims.  What that means is that once you sign up, which you must do if you want to use their technology, you effectively give up your right to sue for infringement of any IPR you might own which is included in or used by the other companies who are implementing the standard.  It doesn’t affect you rights if it’s used by companies outside the standard, or by companies who use the standard, but haven’t signed that agreement - you can still sue them.  In Bluetooth you can’t charge a fee for anyone using your IPR as part of the standard - that’s an RANDZ license (Reasonable and Non Discriminatory - Zero cost).  In ZigBee, in theory you can charge a license to other ZigBee companies, although I don’t think anyone has - that’s a RAND licence (Reasonable and Non Discriminatory, with the emphasis on reasonable). 

This is a two way pact.  Companies agree to give up the right to sue each other, but in turn sign away some of the value of their IP.  The latter can be quite a difficult step for some companies to take.  The use of IP as a competitive tool varies quite widely between different industries.  Some see it as having a defensive value, some as an aggressive means of getting income, other as a bargaining tool.  When you sign this sort of agreement, you’re also signing yourself up for potential future use of your IP that you might consider valuable, because no-one knows what these standards might cover in five or ten years’ time.  That’s something that might make companies with a more conservative approach to IP reluctant to sign.

The benefit of this model is that the more companies you can get to sign the IP license, the more IP goes into the standards pool, so the more protection you’re likely to have from being sued.  Bluetooth is particularly good in that respect, as they have over 13,000 members who have signed up.  ZigBee has around 300.  Before a standard is released, most standards groups do an IP review to see if there are any problems from patents held outside the group and will try to address them.   But none of the standards bodies give any IP guarantees.  If there’s an underlying patent that someone owns, they can come out of the woodwork and sue you.  No standard is immune - that’s already happened to Bluetooth, Wi-Fi and ZigBee.  The question that companies and organisations need to ask is how to compare the risks?

To start, you need to look at just how much a standard covers.  Some standards, like Bluetooth, have written everything from the radio specification up to the application profiles.  So all elements of that specification are covered by the member IP agreement.  Others, like ZigBee, use external standards for the radio and baseband (in their case the IEEE 802.15.4 specification), so the ZigBee agreement provides no IP cover for any of this. 

Even when a standard has written the whole specification itself there are still subtleties.  Z-Wave is a standard that was written to cover the whole stack from radio to application.  But it was written and the IP is owned by one company.  It means that it does not have the safety of 13,000 contributing members for its IP pool which Bluetooth has. On the other hand, it’s a simpler specification, so there’s probably less to infringe.  You don’t really know the answer to this until there are enough products in the market to make it worth an IP owner taking out an injunction.  Bluetooth got past that point a long time ago, as there are billions of Bluetooth devices in the market.  Standards like Z-Wave haven’t shipped enough to make it worth a patent holder suing them and ZigBee is only just at that threshold.

Which brings us to patent trolls.  Many people ask “What is a patent troll?”  Within the PC and telecoms industry it’s long been rumoured that some large companies employ more lawyers than engineers and make more from their patent licenses than they do from selling products.  Whether you think that’s a good business model is up to you, but at least they’re generally trading on their own innovation.  Patent troll is the term applied to companies that specialise in buying up unused patents - often from failed start-up companies, sitting on them until they see a market opportunity and then suing companies who infringe them.  Because they don’t generate their own IP, many in the industry see them as parasites - hence their derogatory name.  (For a nice example of some of the more inventive IP business models, I’d recommend Cory Doctorow’s novel Makers.)

Here is where the uncertainty about the risks come in.  The business model for someone owning some underlying IP is not to go after the first product to appear.  If you do that you may frighten the market off, which would limit your licence revenue.  Instead, you wait until the technology is well established, probably shipping a hundred million units a year and then send out the injunctions.  Typically these will be served against smaller players who can’t afford the legal battle, or the cash-flow hit of having their production stopped.   If they take out a licence, this will be used as legal proof that the industry considers the patent is valid, at which point injunctions will get slapped on the bigger players. 

That approach is taken both by trolls and research institutes that own relevant IP.  It means that the risks and costs of choosing a particular standard may not be felt until four or five years after that decision was made.  As a general rule, it means that standards that have been around longer, have more members and have also shipped more units are safer.  Once a standard has passed the hundred million shipments, most of the trolls will have come out of the woodwork, so you can be pretty clear about the future risks.  If it hasn’t, then you really need to do your homework, and probably put aside five to ten dollars licence contingency for every product you make.  Which is a cost that is generally left out of the PR pitches made by standards bodies.

The corollary is that it also means that more recent standards are more risky.  People owning IP that they think they can make money from keep quiet about it.  And as each year passes, more patents are being granted in this area, increasing the threat for new standards currently being written.  So unless you have the wide membership of a standard like Bluetooth, any new standard, protocol or even profile offers the risk of infringing an ever growing body of IPR.

Any patent owner in this area will have realised by now that they have the potential to put the smart metering industry over a barrel.  The cost of physical deployment is so high, that any infringement will have to end up with a settlement - it’s too costly to replace the wireless portion of millions of meters.  The question those specifying the standards need to ask themselves is whether they’ve fully understand that risk when they make their choices.