Bluetooth SIG Announces Bluetooth Mesh for Large-Scale Device Networks

The month the Bluetooth SIG has taken the wraps off of their latest standards project: an addition to the Bluetooth specification that enables creation of large networks of devices. Dubbed “Bluetooth Mesh”, the new standard is designed for smart homes, public and manufacturing facilities. An extension of the Bluetooth LE protocol, the Bluetooth SIG hopes that the first products supporting the Bluetooth Mesh specification will be quickly available in the coming months as the new technology does not require principally new hardware.

Bluetooth Evolution

The Bluetooth technology was originally developed in the late 1990s to enable wireless device-to-device communications. This device-to-device tech has been evolving since 1997 by improving transfer rates, extending range, and improving reliability. In the early 2000s, researchers and product developers determined that there were many devices that could benefit from short-burst wireless connectivity, but did not need a fully-fledged Bluetooth implementation due to power consumption and size concerns. To this end, developers from Nokia and other companies started to design a low-power version of Bluetooth that was first marketed under the Wibree trademark in 2006 and then became a part of the Bluetooth 4.0 spec under the Bluetooth Smart (Bluetooth LE) trademark.

Bluetooth LE introduced a one-to-many communication paradigm to the standard, enabling various new usage models and applications, such as item finding beacons or way finding beacons. Meanwhile, device-to-device and device-to-many-devices Bluetooth interconnections ultimately use a star topology, and thus such networks have limits to their range and the number of devices in a network, which can inhibit their usage models.

With the introduction of the Bluetooth Mesh standard, the Bluetooth SIG is bringing a many-to-many communication paradigm to the standard. As the name implies, Bluetooth Mesh enables building large-scale device networks with a mesh topology and thus extends the range of a single Bluetooth network virtually to infinity (mind latency and other factors though). In turn, such large networks open up new usage models for the technology, particularly in the field of IoT devices.

How It Works

At a high level, Bluetooth Mesh uses the Bluetooth 4.0 LE protocol to transport data between devices (nodes). This means that from a data transmission point of view, nearly everything has already been specified, from low layer radios to encryption to application layers.

What Bluetooth Mesh adds on top of Bluetooth LE is an ability to retransmit data (a message) from one device to other devices that are in direct radio range (a single hop away) until it reaches the destination — the address it is sent to — using the so-called managed flooding technique. Managed flooding allows the receiver to determine how many hops it’s away from the sender, and thus disable message relaying further than it is needed (i.e., set the maximum number of hops over which the message is retransmitted), thus preserving power and saving the bandwidth of the whole network. This technique ensures that the message always reaches its destination potentially using various paths even if certain nodes fail. Moreover, by not using routing devices, Bluetooth Mesh networks become cheaper and more reliable — messages always get to their destinations no matter what happens to individual nodes within a network (so long as there’s a path).

Under the hood, Bluetooth Mesh networks consist of relay nodes that can retransmit messages, and low-power nodes that connect to relay nodes to periodically transmit or receive data using a mechanism called friendship (i.e., each LP node has a Friend). Low-power nodes could be various sensors or beacons that only use short-burst data transmissions with their “Friends”, which then retransmit their data to other nodes.

The Bluetooth SIG says that a single Bluetooth Mesh network can contain up to 32,767 elements (a node has at least one element, or addressable entity), but admits that in the real world such networks will typically consist of at most thousands, rather than tens of thousands of devices.

When it comes to bandwidth, the gross air data rate of the Bluetooth LE is 1 Mb/s (at maximum transmit power of 10 mW), but this figure does not account for protocol overhead. There are reports that the maximum achievable BLE data rate is around 10 KB/s depending on the devices used. Such data rates are not a problem for point-to-point communications within the contemporary star network topology. However what happens when hundreds of devices start passing numerous messages over the mesh network remains to be seen. Bandwidth, latency (6 ms per hop – the standard for the Bluetooth LE) and lack of priority attributes for data packets could be limiting factors for Bluetooth Mesh adoption in environments that generate loads of data.

It is important to note that the Bluetooth SIG made interoperability a part of the specification development process, and therefore thousands of interoperability tests have already been conducted. This is not exactly surprising as the Bluetooth Mesh spec builds up Bluetooth LE, and therefore existing Bluetooth 4/5-capable chips can support the new technology. Meanwhile, actual contemporary devices may or may not receive firmware and software upgrades to enable Bluetooth Mesh support. Some device makers interested in addressing smart home and other applications are more likely to enable the new spec on existing products, but others are more likely to qualify future products for the new tech.

Use Cases and Competition

At present, the Bluetooth SIG and its members are pursuing several key applications for Bluetooth Mesh: smart home, lighting, beaconing, automation, and asset tracking applications. For example, integrating relay-capable nodes into lighting devices across a home extends range of the network to the whole building. Each of the multiple relay nodes installed in every room can then connect to various low-power nodes, such as temperature sensors, thermostats, window blind controls, and so on. In a warehouse, a robot could navigate its way across the building without any network range-related constraints while enabling operators to track its whereabouts.

The Bluetooth SIG is certainly not alone with its mesh-networking standard for IoT applications, both in general and smart homes in particular. There is ZigBee that is used for various smart home appliances already, there are proprietary technologies, and Wi-Fi HaLow is incoming. A natural advantage that the Bluetooth SIG and its members have is that there are hundreds of millions of Bluetooth-enabled devices produced and sold every year, and therefore the majority of upcoming smartphones, smart TVs, notebooks, tablets, and other products will have the ability to be compatible with the Bluetooth Mesh specification. As a result, it will make a lot of sense for developers of smart home appliances to design devices compatible with Bluetooth Mesh — millions of consumers will have compatible devices in about a year from now, and this is a huge number for an emerging market. Meanwhile, when it comes to custom automation or industrial applications, it remains to be seen which technology developers prefer for their large-scale device networks.

Preliminary Thoughts

Nowadays there are billions of Bluetooth LE-enabled devices, and in the coming years their number will grow further not only because people will buy more smartphones, but because a lot of brand new device types will emerge. The Bluetooth Mesh specification enables building large-scale device networks without the need to launch any new hardware, and thus makers of smart home appliances (and other devices) may begin quickly adopting the new tech in the coming months.

Relying on the Bluetooth LE specification and the managed flooding message transport technique ensures that Bluetooth Mesh-based large-scaled device networks will have predictable performance (RF interference withstanding), known security mechanisms, high reliability, and relatively low costs. Moreover, to a degree the usage Bluetooth LE eliminates the chicken and egg dilemma for the new standard early in its life, as supporting devices are already here. However, it is not completely clear how the number of nodes per single network affects its performance, and that will be a very important factor once large networks consisting of hundreds or thousands of nodes are built.

Keeping in mind that Bluetooth connectivity is ubiquitous nowadays, Bluetooth Mesh has a good chance to become a very popular wireless standard for smart homes and other applications, provided that it can deliver the right performance and ensure compatibility and interoperability between devices from different vendors. The Bluetooth SIG says that interoperability is nearly guaranteed for Bluetooth Mesh supporting devices, but we will have to see how that pans out ourselves.

Otherwise, while developers of smart devices can start building Bluetooth Mesh products based on silicon solutions designed by others, they will still have to complete the long-standing Bluetooth qualification and/or declaration processes in order to ensure that their products satisfy the Bluetooth license the requirements and to pay the appropriate fees. This is not going to be a problem for the established players, but may pose a small challenge for small startups.

Finally, the Bluetooth SIG is naming a number of semiconductor manufacturers, software developers, and device manufacturers as among Bluetooth Mesh’s early adopters. This include 3M, ARM, Ericsson, STMicroelectronics, Qualcomm, Toshiba, and others. While the organization does not announce any final products, it makes it clear that Bluetooth Mesh is has manufacturer support at both the silicon and on-device levels. Moreover, there are turnkey silicon and software solutions available from companies like Cypress, Silicon Labs, and Wisilica to build devices compatible with Bluetooth Mesh. Ultimately, the sky looks blue for the Bluetooth Mesh to take off, but its actual market acceptance will depend on the adoption of IoT devices for homes, offices, and production facilities.

Lower Cost 10GBase-T Switches Coming: 4, 5 and 8-port Aquantia Solutions at ~$30/Port

For users that have been following our recent coverage of Aquantia’s new multi-gigabit Ethernet solutions for consumers, the AQtion AQC107 and AQC108 controllers (along with their corresponding PCIe cards), the running theme through all of the &…

Aquantia Launch AQtion 5G/2.5G/1G Multi-Gigabit Ethernet Cards (NICs) for PCIe

Late last year, Aquantia launched their range of multi-gigabit Ethernet controllers. These were controllers that could enable 1G, 2.5G and 5G connections over standard RJ45 connectors and Cat5e cabling. At the time, the two launched controllers were offered to OEMs to add into their custom motherboard builds, such as enterprise focused machines with a 5G office network in place. We have also seen motherboard manufacturers pick up the mantle, with consumer motherboards such as the ASRock Z270 SuperCarrier and the ASRock X370 Gaming, using the 5G Aquantia AQtion AQC108 chip. 

Today’s announcement cements Aquantia’s lead in the multi-gigabit Ethernet space, despite already having an apparent 2 year lead over other rivals in this space (it helps that Aquantia helped define a major part of the 2.5G/5G specifications in the NBASE-T Alliance). Aquantia is launching two PCIe-based single-port network cards using their AQC108 and AQC107 controllers. 

Both of these cards equip a system with a single port, with the AQC108 based card supporting BASE-T standards from 100M to 1G, 2.5G and 5G and uses a PCIe 3.0 x1 interface. The beefier AQC107 based card supports the same standards as well as 10G, and uses a PCIe 3.0 x4 interface (both cards will work down to PCIe 2.0 x1, with reduced data rates). Drivers for both cards will be available for the Windows 7/8/8.1/10 (also as part of the Windows Update solution) as well as varieties of Linux (3.10, 3.12, 3.2, 4.2 and 4.4).

The idea behind these cards is the same as other network cards – to be able to offer functionality without having to embed the controller on the motherboard or into a prebuilt/legacy system. In the consumer world, we have plenty of offerings of Intel and Realtek based gigabit Ethernet cards (even Killer NICs back in the day), and Intel commands the 10GBASE-T cards with its X540 and X550 series. Aquantia is hoping to shake up this market, particularly for businesses and end users willing to invest in 2.5G/5G infrastructure.

One of the big questions surrounding the transition to 2.5G/5G for home and SMB is infrastructure – making sure the network backbone, switches and access points are all capable. The major enterprise network players are already deploying multi-gigabit Ethernet networks to their customers, however it will be a bit longer before commercially available switches for consumers are available. One of the major drawbacks investing in 10GBASE-T in the home right now, aside from the $100-200 per port PCIe cards, is the cost of the switches. This is something Aquantia isn’t doing directly, but we have been told that they are working with partners (the typical enterprise players at least) to solve. The depth of those solutions remain to be seen (we’ve been told similar by 10G switch vendors who had a different interpretation of ‘mass market’), but ultimately for this technology to become ubiquitous, we need to see cheaper switches ($25/port), followed by cheap implementations, as we have seen in the last 15-20 years with gigabit Ethernet. 

Final pricing is set at $99 and $127, with the 5G card being cheaper over the 10G card. Aquantia stated in the briefing that they are planning to sell the cards direct to consumers, or OEMs can brand the cards in their own style (eg imagine gaming based cards, as we’ve seen from Gigabyte already, or ASUS and their recently announced ROG Areion 10G card using the AQC107 chip) for their customers. It would be interesting to see if a manufacturer will offer a multi-port card by placing 2-4 chips on the same PCB, even if it requires a basic PLX switch.  Four 1G/2.5G/5G/10G ports for $549, anyone?

Gallery: Aquantia AQtion NICs

Review samples are currently being circulated, and I’m discussing with Ganesh the best way to test them, especially as we don’t have any 5G switch equipment. We’re also looking at angles to test these ports as they appear on motherboards too. Aquantia expects the cards to be on shelves shortly, with branded cards to follow. 

Gallery: Aquantia Press Slide Deck

Related Reading

• GIGABYTE Exhibits an Aquantia AQC107 based 10G Ethernet PCIe Card
• Aquantia Launches New 2.5G/5G Multi-Gigabit Network Controllers for PCs
• Consumer 10GBASE-T Options: Motherboards with 10G Built-In