Mister Beacon Episode #53

Bluetooth Mesh – Szymon Slupik

October 04, 2017

Bluetooth Mesh is perhaps the biggest thing to happen to IoT since Bluetooth Low Energy sparked the revolution of beacon technology, wearables and thousands of other connected products. Szymon Slupik, CTO of Silvair and Chair of the Bluetooth Mesh Working Group at Bluetooth SIG explains what the release of this new standard means, what mesh is, why it was necessary and the applications that it enables.


  • Steve Statler 00:06

    Bluetooth Mesh is arguably the biggest thing to happen to IoT since Bluetooth Low Energy sparked the revolution of beacon technology, wearables and 1000s of other products have driven the sale of billions of devices. We spoke to Szymon Slupik peak CTO of Silvair, and chair of the Mesh Working Group at the Bluetooth SIG, and asked him to explain what the release of this new standard means, what Mesh is, why it was necessary, and the applications that it enables. We hope you find this useful. Don't forget to subscribe to us on the Mr. Beacon website, YouTube, Facebook, or your favorite audio podcast platform. Simon, thanks for coming and doing the Mr. Beacon podcast with us. In the in the Bluetooth world, you're a bit of a celebrity at the moment, because you chaired the Bluetooth Mesh Working Group. So you've been busy? And can you first of all start off just by telling us what's what's new with Bluetooth Mesh, what's just happened?

    Szymon Slupik 01:14

    Adoption has just happened. And adoption is like the crowning moment in development of a specification that becomes part of the broad blue standard. So adoption is the moment when everything's ready, everything's proven to be interoperable, tested, and we unveil it to the world. So the Mesh is now adopted, which means products can start using that spec and products can be listed, which is the Bluetooth SIG term for binding contract in some way between product vendor and the organization that holds the intellectual property rights to those specs. And those products could hit the market. So this is becoming very exciting. Now, you know, the long work and now products come to fruition and and they show up.

    Steve Statler 02:15

    Very cool. Congratulations on that. In our discussions today, what I'd like to do is just have you talked to us a bit about what Mesh is, what it means and what the applications are. But before we get into that, how long has it taken to getting this actually into a released state.

    Szymon Slupik 02:34

    Depending on what you consider a starting point. So formally, we started a Bluetooth Mesh study group in 2014, second half of 2014. And that study group was formed to work on functional requirements. After the study group completed the collection of requirements and formulated and Frd document, Working Group was formed. And that was the first meeting of the Mesh Working Group was early February 2015. So if you take that as a starting point, it's two years and a half.

    Steve Statler 03:20

    That's a significant amount of work. And it's a really big deal. I think, you know, we had Bluetooth we had Bluetooth low energy, or Bluetooth smart, I should say. And now Now we've got Bluetooth Mesh is will Bluetooth Mesh products have their own brand, or will they just be using the Bluetooth today?

    Szymon Slupik 03:40

    Bluetooth is using just a single brand Bluetooth because like it makes things simple. Of course, under that brand umbrella, you have a variety of specifications, products, use cases, they all use the same fundamental technology, the same fundamental radio technology that powers all of them. So that's the common denominator.

    Steve Statler 04:06

    And explain to us just briefly what what is Mesh?

    Szymon Slupik 04:10

    Yeah, so Mesh, depending on like which angle you look at it, but it's it's a network, it's a low power or I would say even ultra low power networking system peer to peer network. So it is a new topology for devices that use Bluetooth radios. So you know, Bluetooth started back 19 years ago with of course audio was the first application and that was over. Point to point link. And this is how it still is today. Like your phone to your headset is point to point link. Then, in 2010 Bluetooth Low Energy was integrated into Bluetooth wireless and low energy, it offers point to point links, not for audio, but for low data rates, devices like accessories, activity trackers, you know, it enabled all these in market have have accessory devices, human interface devices that connect to a central device that's in the middle. So Bluetooth offers today this topology of several point to point links that hooked to the central hub, which usually is your smartphone or your PC computer. Low Energy also enabled applications that use one to many topology, you've probably probably you're of course heard of beacons, because you're running the beacon business and, and so beacons is a new phenomena in Bluetooth, enabled by low energy and it's really I want to many broadcasts falls. Because you don't have connections, you have a device that broadcasts data and you have many devices around it ad hoc that can make use of that data interpret that in variety of ways. Now mash, it introduces many to many peer to peer connectivity. So you can have a complete network of devices, 1000s of them organized in a network. So they all share security credentials, and they all have their own addresses, and you have unicast addresses and you can have group devices, group addresses for grouping devices and Mesh organizes that system. That's the so actually, the Mesh specification is three specifications. So the first fundamental is the Mesh profile. It's the networking part security networking, as we're seeing communication, publish, subscribe how two devices communicate, you doesn't defined what they are telling each other what information they exchange. So on top of the Mesh profile, we have a Mesh model spec that is an application layer, it defines things, how they behave, how they react, who can talk to who about what. So in that match model spec, we have four main areas one is called generics, which is used to generically control any type of a device. So it contains things like binary on off commands, so you can switch on your lights, or you can switch on off any other device. And you have analog levels. So you can, for example, sent a message that that controls level of something or that something can report the level of itself, whatever it is, that's why we call it generics. Second part of the profile spec of the model spec is sensors. And that's very important because it's very flexible. And it builds on a system of gait characteristics that has been developed for a number of years. And Mesh sensors built on top of that. So we are enabling any type of a sensor to be managed device, including things that we refer to as multi sensors. So there's several sensors in one. So you can envision things like occupancy sensors combined with ambient light, and they are very popular in lighting applications. And you can have temperature, you can have other environmental that's kind of addressing this category of devices, but also within the sensor models. We have what we also refer to as sensors, we have means of reporting, variety of statistics and maintenance data. So actually, any device in IoT world can benefit from collecting and reporting its own data.

    Steve Statler 09:27

    And how flexible is that to do?

    Szymon Slupik 09:30

    It's designed to be ultra flexible. So So probably we covering today, north of 90x percent of sensor applications out there. Now, if anything is missing, for example, there is a very unique type of a sensor that we haven't envisioned. The good news is that the spec already covers that in some way. The only way that needs to be defined is the format and the meaning of the data. So you may say, Okay, I have a device that reports, whatever fluctuations of sunburn on on his skin, whatever, and you define that as a 16 bit value or 50 bit value or whatever you like. And then you apply to blue to seek to assign an identifier for your type of sensors, so that once somebody hears that sequence of the identifier and data, they know how to interpret that. So that's designed to be very quick turnaround cycle, you know, so, so, if any new needs arise, we can satisfy them almost immediately. Then, third part of the model spec is time, and connected to that since and schedules. So time we consider very important because propagation of time across networks is something that may bring very important value to many, many applications. So you know, today, probably, you can count the number of of devices that display time in your home. And, and they are not synchronized usually. And very often they like Blink, and with zeros, or they don't have the current readings when the daylight savings is on or off. So we see that as a very fundamental application. For the time models, all those devices can form a Mesh network and tell each other what time it is. The other thing, as long as a device has a notion of time, it can have a table of schedules so that it can be a blind sunblind, for example, that shuts down an app, depending on the program schedule, or they can be variety of other use cases when they are time driven. So that's what the time is about. And finally, finally, finally, last but not least, is the lighting part of the model spec. And that lighting part is really very deep, I would say address is not just simple home lights, but it addresses the needs of professional lighting industry. So this is a completely new territory for Bluetooth, to innovate. And I'm very curious to see what is the reaction of lighting companies when they go through the spec and when they see the products. But the good news is that leading lighting companies were contributing to that specification. So we believe it's very solid.

    Steve Statler 12:44

    And I was going to ask you who's actually been working on this, because I think that tells us something the kind of companies that have been involved in this massive effort tells us where it's gonna be.

    Szymon Slupik 12:53

    So the main contributors are listed on one of the initial page of each specifications. So you have the Mesh profile spec, Mesh, model, spec, and Mesh properties, which is the third one. And, of course, you have traditional companies who have always been there, which are cheap vendors, companies who produce blue silicone that surrounds all those applications. So, so I won't be going through all the names. You know, that's the case. The other companies that we are very happy to have fanboys are the big guys like Google, for example. So So Google has actively contributed to the spike. And of course, they are listed as a contributor in the spec. And finally, there are few companies like ours. So we are a fairly young startup. And, and for us, this has been a great experience to be among all those big players and plays such an important role in defining and developing that spec. So Silvair, my company is a software lighting control company. That's how we define ourselves. So so we, our product is software stacks and applications and platforms for organizing lighting systems, and Bluetooth Mesh is the primary platform slash technology to achieve that goal.

    Steve Statler 14:26

    So you really had a you had some skin in the game, this had to work because Silvair's business and you're the CEO of that business is sitting on top of this.

    Szymon Slupik 14:34

    Yes. So for us, you know, it's been very significant, but and I would say binary bet. I mean, we bet everything on the technology and for a reason, of course so so we had not the greatest experience with other technologies and we quickly realized It was somewhere around 2012 13 that that really, we want to use Bluetooth for. Fundamentally, this radio is the best radio of choice available today for this kind of applications.

    Steve Statler 15:17

    And yeah, yeah, so why not other radio technologies like I mean, ZigBee is famous for having some Mesh functionality in it.

    Szymon Slupik 15:25

    Yeah, we played with ZigBee and related technologies before going to Bluetooth, and we, it was a great learning experience. So we built our second generation lighting control system based on ZigBee, radio and on what we consider the time the best breed of other technologies and layers. So it was a full ipv6 solution based on ZigBee in sub gigahertz frequencies. So it seemed to have all the properties of a winning system. So it was easily traversing concrete walls. And it was, you know, IP based, and it was like everything. And then the final product didn't work. Because we found it simply too slow and, and too heavy. And it's like, I like using that paradigm a lot. It's like building the next generation aircraft, using steel as your primary material, you can build a beautiful thing, it just won't fly. So we learned that you have to start with a proper foundation, like, you know, modern aircraft are built from from latest generation composites. So So for us, Bluetooth radio is like this fundamental building block that guarantees that we will get the best performance.

    Steve Statler 17:01

    So you can have a great standard, but obviously key to any standard is adoption. And what's your view on where this is going to be adopted? And how confident are you that this is going to be kind of live up to the rest of the Bluetooth standard?

    Szymon Slupik 17:14

    Yeah. So we've taken care of that, to some extent, when defining the requirements for the specification. So one of the fundamental requirements for Mesh has been that it is backwards compatible with Bluetooth four. So it means that in a nutshell, it's a software upgrade for existing Bluetooth devices. Of course, they have to have enough resources like flash memory, RAM, and things like that. And the vendors have to provide that update. But but it's only quote only a software updates to everything that's out there. So your existing phones, they can do much today.

    Steve Statler 18:00

    Or Bluetooth beacon, if I get a firmware upgrade, yeah.

    Szymon Slupik 18:03

    If you, if you absolutely, yeah, that's, that's, that's the key. So of course, this approach has a drawback that we are not based on the latest, greatest Bluetooth five radio, which improves things even more. But Mesh, by principle has been designed for very rapid market adoption. And to prove that on day zero, so the day of launch, two vendors, we were one of them, qualified their stacks. So on day zero, at the day of adoption, you had, you know, two qualified software stacks for for Mesh available. That's something bluetest Five is still in the process of being developed into products Mesh is you could say already developed. So now companies are building and products that will be hitting the market very soon.

    Steve Statler 19:06

    Let's talk about scalability, because that's got to be one of the challenges with these Mesh networks, they can potentially be very large, and you've got nodes that are running on batteries. How can you say anything about how you're going to make sure that this sort of flooding of packets doesn't wear down all the batteries and exhaust the network?

    Szymon Slupik 19:29

    Yeah, it's it's a significant problem I've made and we have what we believe very good means of addressing that problem. So there are a number of techniques that the specification and visions to enable scalability. So again, you know, it starts with the radio itself. That's way lighter way faster than anything comparable. So a single Mesh message it occupies only 376 Micro seconds of airtime on a given frequency. So that's 10 times better than anything else available. You mentioned those other technologies. So we have an advantage here from the very start. And then the architecture of the system is such that it enables, through planning, such deployment of those networks that they can really lead reach a high number of nodes. So we have networks, in pilot projects that are north of 1000 devices, and we know there is still room to have more, I would say where other comparable networks say they are going to saturate, we are running just fine. And that's because of the lightweight design. So I was talking about how the radio helps, but also what helps a lot. And I believe that's the very unique design proposed for mash is that I mentioned message is very, very small. So without compromising on security, which is always the biggest overhead on transport payloads, we are able to squeeze the entire Mesh message into a single Bluetooth advertising PDU, which is including all the preambles and thanks for the something octopus is very small.

    Steve Statler 21:34

    And without going into a lot of detail. Can you just give us a sense of are there different roles within a Mesh network? Like if I have a battery beacon and a powered beacon? Are they going to behave the same or differently?

    Szymon Slupik 21:45

    Yeah, they can behave differently. So we have support for low power nodes through concepts of friendship. So that concept allows those low power devices achieve very low duty cycles. So essentially, you can have a device that sleeps all the time and wakes up only to for a few hundreds of microseconds to transmit something. And then the friendship concept works kind of like a email inbox. So that device can have higher power more capable friend device that helps caching messages directed towards the low power. So that friend maintains a cache of messages and a low power device like a bathroom beacon wakes up once in a while, pings the friend device. Hey, do you have anything for me? If not, then it goes to sleep immediately. So so that well rounded to three? three decimal places, actually, it's 0.00. Do the cycle. So we can run for years?

    Steve Statler 22:56

    Well, I just want to wrap up. But before we go, any thoughts on what what do you think the new applications are? We've got this new standard, this new capability. How do you expect this to impact the applications of Bluetooth in the future? Are there new things that are going to be possible that weren't possible before?

    Szymon Slupik 23:15

    Yeah, of course. So you know, I envision and we are using lighting by purpose on purpose. I envision significant rollouts of Bluetooth Mesh communication fabric as digital ceilings. So of course, the key motivator for that today is is energy savings and lighting control which Bluetooth Mesh can satisfy by design. But once you have those lights in your ceilings that form a Mesh network, they can be used to do many other things. So a light, for example, can receive advertisements, bloopers advertisements from asset packs. And these advertisements can be forwarded through the network to client applications that makes you make use of that information. So you can envision all sorts of asset tracking ad hoc sensory applications being enabled by that, of course. First, we need to have the widespread rollout of those Digital's ceilings, but I believe that will be happening fairly soon. And then beacons mentioned here a number of times. So I believe one problem in large scale, beacon rollouts has been the lack of standardized management interface for beacons. So beacons today can advertise but from time to time Um, you need to reconfigure them check their status, reprogram them in some way. And there's no standard way of doing that. So, so Mesh aims to address this this problem. And this is one of our near term roadmap items to add to Mesh beacon management. And there are a couple of other work proposals that call for using Mesh networks for new applications. So so the source of that is, as always, Bluetooth website and the specification workspace. So, you know, your proposals can be browsed. So I encourage people who are interested in our roadmap to just go there and look into what is in there. And if you find something interesting, then please join the group and contribute. We are member driven. And all that happens. I'm just trying to facilitate and it's really those people from individual companies who come and devote their time and effort to build the specification.

    Steve Statler 26:08

    Well, that's quite an achievement. It's exciting. It sounds like it's really the end of the beginning. And there's a lot, a lot of work to come and a lot of new features and developments. Thanks very much for sharing all this great information.

    Szymon Slupik 26:21

    Would say it's even beginning of the beginning. So yeah, we are, you know, v1, it's a great system, but just released and it just opens the imagination of what can be in front of us. So I'm very excited to see.

    Steve Statler 26:36

    Simon thanks so much. Appreciate it.

    Szymon Slupik 26:38

    Thank you very much.

    Steve Statler 26:45

    What three songs would you take on a trip to Mars?

    Szymon Slupik 26:49

    When is the trip scheduled?

    Steve Statler 26:52

    In about three months?

    Szymon Slupik 26:54

    Okay. Just laughing because, yeah, I've had such problem before. So it was way back into very early 90s or even 1989. I was on a trip to Australia, from Poland, and for a year and I had to like, make a very careful selection because like, the only thing I could take with me was cassette tape. So actually, I took two at that time. One was Robert Plants, Blog, okay, which is still on top of my favorites list. And the second at that time, it was very popular, but I still love and it keeps reminding me of many emotions of the days that those days is Home by the Sea by Genetics.

    Steve Statler 27:57

    Okay, Genesis. Wow, I think that's a first for our shows.

    Szymon Slupik 28:01

    And so that's to say one that's actually coming back to me quite frequently is probably less known. The title of the song is I hear and the name of the band is strange people. It's you can find it when you look for it. And it's got a number of very nice remixes transfer mixes, which I also like. So it's a variety of you know, different flavors, but I think that was me running very good.

    Steve Statler 28:42

    So you're a runner?

    Szymon Slupik 28:44

    Runner, biker, but yeah, I do like activities. So, snowboarding in winter. You know, we have many opportunities for that in in Europe.

    Steve Statler 28:58

    And you're based in Poland?

    Szymon Slupik 28:59

    I'm based in Poland. Yes. So Austrian Alps with offices where we love to go and also I live I love hiking, a lot backpacking.

    Steve Statler 29:13

    Alright, sounds like you got a good work life balance. That's to be commended.

    Szymon Slupik 29:16

    Trying to trying to although I tend to be very emotionally attached to things I'm doing so like, development of mash was like my personal story a lot, not only my business stories.

    Steve Statler 29:33

    Very good. Well, thanks for that.