Building 5G: NB-IoT
November 10, 2016 Leave a comment
- NB-IoT is often invoked in discussions of next-generation wireless network evolutions as part of “paving the way to 5G.”
- While there is no way to interpret NB-IoT as a 5G technology, it provides a “bridge” to the massive IoT capabilities that 5G promise, giving operators insight into IoT opportunities and tool to address many of them.
Our blog post from late October highlighted a fundamental MEC dynamic: while MEC is fundamental to 5G, it’s not strictly a 5G concept. It can be deployed well before 5G becomes a commercial reality.
This same dynamic is at play with NB-IoT. It’s here today, but expected to be critical to 5G in the future.
An evolution of LTE, nobody considers NB-IoT a 5G technology. And yet that doesn’t stop NB-IoT from getting routinely called out as part of the “race” to 5G or “paving the way” to 5G. At the same time, the move to accelerate NB-IoT commercialization started in 2015 with demos from Ericsson, Nokia and Intel at MWC this year. Just last month, then, we saw Vodafone announce plans for commercial NB-IoT networks in Germany, Ireland, the Netherlands and Spain to be launched in Q1 2017. Not to be bested, T-Mobile Netherlands almost simultaneously revealed that they would have NB-IoT up and running in major cities before October came to an end.
But if NB-IoT is getting rolled out in the here-and-now – well ahead of 5G standardization – why is it being invoked in conversations around 5G? Is this just a case of marketing gone wild? How do we square this circle?
To clarify, here’s some background on what NB-IoT does and where it came from. Included in 3GPP release 13, NB-IoT provides symmetrical, low data rate (150 kbps peak) connectivity requiring minimal spectrum resources (200 kHz) and an LTE foundation. As Vodafone’s Luke Ibbetson (Chair of the NB-IoT Forum) has highlighted, these characteristics bring welcome benefits to the service provider. The use of licensed spectrum supports service assurance, with 200 kHz channel bandwidth allowing deployment within existing LTE carriers or guard-bands. Two-way communications enable diverse use cases. Low-order modulation supports broad coverage. Ultimately, cellular IoT will need to support myriad use cases including low-bandwidth and broadband applications at an aggressive price point. In the here and now, NB-IoT gives it a jumpstart by delivering a low power wide area (LPWA) technology designed to leverage existing LTE networks in support of hard-to-reach IoT devices that may require infrequent reporting of small amounts of data. Simple enough, right?
Against this backdrop, then, we can ask how it aligns with core 5G use cases.
- Massive IoT. NB-IoT is all about enabling widespread IoT. But beyond the technical benefits called out above, a focus on cost containment is probably its biggest strength. By leveraging an existing LTE ecosystem, providing broad coverage, and delivering long battery life (along with inexpensive modules), NB-IoT is a technology designed to take IoT from niche to mainstream.
- Critical Communications. Many critical communications use cases will also be IoT use cases. A fair share will require lots of bandwidth. Many, however, are just as likely to be narrowband applications, yet still requiring the service quality implied by use of licensed spectrum. Ultra low-latency applications may still require dedicated networks or 5G builds, but NB-IoT should fit the bill for many critical applications. Think water supply monitoring as an example.
- Enhanced Mobile Broadband. You’d be forgiven for not immediately seeing a link between low-bandwidth IoT connectivity and mobile broadband use cases. While NB-IoT won’t help deliver high data rates – it was engineered largely around sensor-based use cases – it will support them by offloading IoT applications from broadband networks and supporting IoT in spectrally flexible ways (conserving spectrum for mobile broadband).
Beyond today’s implementations, future NB-IoT evolutions will help the technology serve more IoT use cases with a variety of diverse requirements, and this is important: different IoT applications have very different requirements on features, performance, coverage, battery life and the like, which will need to be supported in future standards iterations on the way to 5G. Release 14 proposes, for example, enhancements including voice support, mobility support, and location services. Broadcast support, meanwhile, should deliver efficient firmware updates to a wide array of IoT devices. 5G, then promises even further IoT enhancements in the form of narrowband 5G, meshing, mission-critical control, not to mention the addition of network slicing for flexible use case support (again, more on that in a later post).
And this is where the link between 5G and NB-IoT becomes clearer. (Source: Ericsson)
In the near-term, enhanced mobile broadband use cases will dominate early 5G interests (they are flashy, after all) and standardization efforts – potentially. Meanwhile, operators and enterprises will ramp up their IoT deployments looking for efficient solutions and not necessarily wanting to wait (potentially a while) for narrowband 5G. NB-IoT, then, provides a foundation for those deployments, delivering scalable IoT capabilities while waiting on 5G-based IoT. As much as it might get positioned as part of a “race to 5G,” a “bridge” might be the better analogy – a bridge where 4.5G technologies help service providers connect a wave of new devices, helping them rethink the definition of a “device” and the IoT business models in the process. Given the maturity of LTE and the fact that LTE networks won’t be getting torn down anytime soon, it’s likely to be a long bridge with lots of traffic crossing it.