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Break down cellular IoT connectivity options

IoT devices can connect using cellular standards or unlicensed LPWAN frequencies depending on what requirements organizations need for their specific use cases.

With the multitude of unlicensed and cellular IoT connectivity options, tech experts starting their IoT initiatives might get confused with the array of acronyms and network types. IT experts must understand the available connectivity options, which work best for different uses and why they might not always use cellular IoT standards.

Tech experts might have to consider using different networks for their IoT devices because of the device capabilities available. Combining different connectivity methods can also lead to interoperability issues that make managing IoT devices and data complex. IT experts must also consider how distributed IoT technology varies in its inherent security and data management. The continued development of connectivity options works to address these issues, and 5G developments could make some headway to bring IoT devices under one network.

The common connectivity options for IoT fall on a spectrum of different throughputs and use cases. Standards organizations also continue to develop and improve common cellular IoT connectivity options to try to simplify the current complex state of IoT connectivity.

"If you bought anything new today, your choices would be, 'What flavor of 4G am I going to choose?' Or, 'I may choose to go with an unlicensed technology, like LoRaWAN,'" said Brian Partridge, vice president of infrastructure, DevOps and IoT at 451 Research.

On the lower end of throughput and battery power, organizations use LPWAN options including narrowband IoT (NB-IoT) and LoRaWAN. On the higher throughput end of the spectrum, organizations use 4G and 5G. Selecting the wrong connectivity technology can affect the costs, coverage, flexibility and longevity of an IoT network.

"5G today is about enhanced mobile broadband, which are really fat pipes. And then NB-IoT sits on the other end of that spectrum, which is a really, really tiny pipe, cheaper and better battery life," Partridge said.

In order to decide which cellular connectivity option is best for an IoT project, IT pros need to weigh device requirements and project goals.

Data rates and uses of IoT connectivity options

What are the LPWAN connectivity options?

Organizations that need their devices to work in the field with a long range, extended battery life and lower costs would use LPWAN connectivity options, said Samuel Ropert, head of smart verticals and IoT practice at iDate DigiWorld, in the webinar titled "Technology Innovation for Optimized Global IoT Connectivity from LPWAN to 5G technologies."

By 2025, the LPWAN IoT market will have more than 1.7 billion objects, a 35% compound annual growth rate (CAGR) from 2020 to 2025, according to iBasis, a communication services provider based in Lexington, Mass. LPWAN connectivity breaks down into two categories: unlicensed and licensed frequencies.

Unlicensed technologies can serve some organizations better than cellular options because they are cheaper, but they often perform slower than licensed standard technology. Approximately 25 different LPWAN technologies use unlicensed frequencies, with Sigfox and LoRaWAN more widely used, Ropert said in the webinar. Each technology has different advantages. For example, Sigfox, is a proprietary public network designed for IoT with activated roaming, and LoRaWAN serves as a private network.

Organizations only have two LPWAN cellular IoT connectivity options: NB-IoT and LTE-M. These two low-power options are the newest members of the 4G family and will carry over into 5G in 3GPP's release 17. The cellular connectivity options cost more than unlicensed versions because organizations must have a data plan with a public network provider.

"What we see is more demand for LTE-M in our customers, but, over time, we believe it will start transitioning to NB-IoT because there are more networks that are deploying NB-IoT," said iBasis CTO Ajay Joseph. "The stuff we see in the field is LTE-M is a lot easier to work with."

NB-IoT and LTE-M are standardized and offer credibility to industrial IoT applications but currently do not include all of the features organizations might want, such as roaming. 3GPP is working on roaming for NB-IoT now and LTE-M roaming does work, Joseph said. Both NB-IoT and LTE-M use low power, but LTE-M has a higher throughput than NB-IoT and does not preserve battery life to the same degree, he said. If organizations need longer battery life, then NB-IoT is the better choice. For example, NB-IoT could be used for low-powered devices that monitor the level of garbage in trash cans.

"In terms of distribution, NB-IoT is expected to be the main [LPWAN] technology and by far," Ropert said.

As of January 2020, mobile network operators had deployed three times as many NB-IoT network devices as LTE-M devices, according to GSMA. Both NB-IoT and LTE-M will see 37% expected growth CAGR from 2020 to 2025, according to iBasis.

5G promises greater support on one network

Cellular 4G provides organizations with connectivity for IoT deployments that need greater data throughput. 5G also offers this advantage, but at a higher magnitude and scale and gives critical communication lower latency, Joseph said in the webinar. Providers are still rolling out 5G networks and it is only available in select places.

"The big advantage of cellular is that it is licensed. It's running over the licensed spectrum, which means no interference, a higher-quality connection, less dropped connections," Partridge said.

In terms of distribution, NB-IoT is expected to be the main [LPWAN] technology and by far.
Samuel RopertHead of smart verticals and IoT practice, iDate Digiworld

The main differences between 4G and 5G for IoT are the data rate and latency. 4G provides 100 Mbps and has a typical latency of 10 milliseconds (ms). 5G provides 20 Gbps and sees about 1 ms of latency. These key differences make each option better for different uses. Organizations using 4G for IoT deployments would switch to 5G for lower latency, which is vital for applications that require real-time communication and analysis, such as vehicle-to-vehicle communication, Joseph said.

Today, a factory making cars or industrial machines would have robots, sensors and connected machines using different networks, including a wired network using industrial protocols, some Wi-Fi and a lot of Ethernet, said Partridge.

"In other words, it's a big fragmented mess of a network," Partridge said. "The promise of 5G is to be able to replace that mess with a single deployment of 5G to support all the connection requirements in the business."

The wireless aspect of cellular networks offers cost savings and flexibility. Organizations can change the factory floor layout without worrying about physical network cables and use the connection for real-time analysis of data from devices, such as high-definition cameras or sensors on pallets in the supply chain.

New technology with 5G will further shape future of connectivity

Continued 5G releases improve on cellular IoT and push connectivity options to serve more IoT use cases under one network. By 2023, organizations will have 5G network options for high bandwidth and NB-IoT and new radio (NR) Light, Partridge said. As part of release 17 of 5G, 3GPP will introduce the new radio technology called NR Light, which will support use cases that NB-IoT does not cover and on the same network. NR Light will offer higher data throughput and lower latency, which organizations can use for IoT devices such as security cameras or wearables.

"The most important takeaway is that the standards are bringing forward the LTE, LTE IoT-friendly variants," Partridge said. "An investment in a narrowband IoT solution today is not going to go out the window in two years because of 5G."

The question remains, who is going to deliver 5G? In the U.S., the Federal Communications Commission is rolling out Citizens Broadband Radio Services (CBRS) to give enterprises access to licensed spectrum repatriated from radar systems used by the Navy, Partridge said. CBRS is going to support 5G. Organizations can get CBRS cheap and deploy their own 5G private network, or an operator can use CBRS to run a private network on behalf of a customer.

"This CBRS spectrum is that Goldilocks spectrum, which is mid-band 3.5 gigahertz," Partridge said. "What that means is it's the spectrum that has the best combination of performance and propagation, such that if you deploy it, you're going to get really strong performance. Things like a leaf won't take the network down. It's going to penetrate walls and get to the devices."

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