Four reasons why LTE networks are not IIoT-ready

As well as four reasons why kinetic mesh is a better broadband solution for the manufacturing industry.

By Todd Rigby, Rajant Corp. September 2, 2018

The Industrial Internet of Things (IIoT) melds enterprise information technology (IT) with operations technology (OT). It gives manufacturers the ability to deliver real-time operational intelligence to the right operator, in the right place, and at the right time. It signals a shift from reactive to predictive response for machine optimization. It is an opportunity to increase revenues with data-driven operational performance optimization and new service offerings.

Wireless industrial equipment sensors, cloud computing, robotics, wearables, and augmented and virtual reality (AR/VR), as well as advanced analytics, all contribute to this information-rich environment. Picture a virtual Rube Goldberg machine made of connected devices—each one on its own performing separate tasks that, taken together, have big impact—and you get an idea how important IIoT will be for manufacturers.

First, however, there are significant challenges to overcome. 

Network challenges

IIoT applications place pressure on the networks on which they run-remember, the second ‘I’ in IIoT is "internet," and there is no IIoT without it-and complex quad-play services (data, voice, video, and control) require reliable high-bandwidth availability.

The IIoT will expand continuously due to the almost limitless number of devices and machines that can be integrated. A network must support rapid scalability, without losing speed or adding latency. The rugged environments in which industrial networks are deployed subject network infrastructure to shock, vibration, and temperature extremes, which the network elements must be able to withstand.

Moreover, cybersecurity concerns persist based on connectivity to an enterprise network and the broader Internet, creating inherent vulnerabilities and risk.

Finally, the mission-critical nature of IIoT applications requires fast recovery times and unwavering mobile connectivity to ensure uninterrupted operations, without negative impact on productivity or safety.

A manufacturer looking to exploit IIoT connectivity must address a range of technologies in a tiered communication system: Local area network (LAN) in the plant and offices; interlink or backhaul situated between the corporate LAN and broadband; then a broadband wireless solution, which may be point-to-point (PtP), point-to-multipoint (PtMP), long-term evolution (LTE), or fiber. At the process level, SCADA or another control system is likely present.

It is by way of the broadband wireless solution—the last step of connectivity—that sensors and controls are linked. In many environments, achieving this connection presents challenges.

In the quest to identify broadband wireless solutions that support IIoT, manufacturing plants are considering implementing LTE, a 4G wireless communication standard developed by the 3rd Generation Partnership Project, LTE delivers up to 10 times the speeds of 3G networks for mobile devices. However, even LTE networks are challenged when it comes to bandwidth/speed, flexibility, reliability, and scalability-all virtues of a truly IIoT-ready network.

Reasons LTE is not ready

LTE networks have advantages for some use cases, including consumer-grade wireless connectivity, but they simply are not capable of supporting IIoT initiatives. Here are four reasons why.

No. 1: LTE has bandwidth/speed challenges

In LTE, different nodes perform different functions. Infrastructure nodes act as access points, while mobile nodes only can pass data to infrastructure nodes.

LTE clients cannot pass data directly to or communicate directly with another LTE client device without first talking to infrastructure (a cell site), then to a switch, and back again.

LTE networks are designed with large infrastructure to maximize coverage. The towers are tall, but there are fewer of them spread across an area, which creates coverage challenges for these networks. We’ve all experienced weaker signals on cell phones when driving down the backside of a hill, under a freeway overpass, or inside certain buildings.

This makes LTE sufficient for delay-tolerant apps like smart metering, but it lacks the agility to support real-time IIoT platforms like machine-to-machine communications (M2M) or autonomy.

No. 2: LTE networks are inflexible

LTE infrastructure does not adapt well to rapid increases in client density. A cell site has a fixed number of connections it can support, making it easy to overload the infrastructure connection capacity. LTE infrastructure also have elaborate, static configurations that are not adaptable.

No. 3: LTE networks lack reliability

A network that relies on infrastructure nodes creates points of failure. If an infrastructure node goes down, its mobile clients cannot access the network. Additionally, infrastructure and mobile nodes access only their respective dedicated frequencies, and loss of line-of-sight can create connectivity challenges. There is no real way around signal blockage or interference. Manufacturers are left with two choices: incur downtime or invest in a second network as a backup plan. Both come at high cost, and neither is ideal.

The stakes are high when mission-critical IIoT applications go down. The rugged nature of industrial operations, combined with the need for 100% uptime, makes LTE a gamble without having ruggedized equipment. When a network is seen as requiring a back-up from the get-go, it’s a red flag when it comes to ensuring IIoT connectivity. A network should be "one and done."

No. 4: LTE is prohibitively expensive to scale.

Expanding LTE networks requires installing large, expensive new towers. Additionally, LTE networks have static configurations and only support a limited number of simultaneous connections.

This expense creates issues for industrial companies hoping to use an LTE network as the broadband layer of their IIoT infrastructure. IIoT embodies an explosion of machine devices and applications at volumes that cellular networks are not equipped to handle. The number of connected "things" in the industrial operating environment will continue to grow, and IIoT applications like machine-to-machine (M2M) will involve a huge number of devices that generate sporadic transmissions of short packets. LTE would struggle under the weight of the signaling traffic M2M will generate. 

A better option for IIoT

A network type called kinetic mesh can overcome the IIoT challenges that LTE can’t. With kinetic mesh, nodes continuously and instantaneously route data through the best available traffic path and frequency.

For starters, kinetic mesh has the bandwidth and speed to handle IIoT. In kinetic mesh, all nodes are equal, and can be interchangeably fixed or mobile. If a device can see another, it can talk to it, communicating on a peer-to-peer basis. Intermediary equipment can be introduced as devices move farther away from each other, making networks efficiently scalable.

Kinetic mesh is full duplex, meaning data can be received by a node on one frequency and sent in another frequency, which creates unwavering high-speed transmission and ensures extremely low latency. The network uses all available frequencies and paths for all network functions, allowing it to deliver data with ultra-low latency to support real-time, bandwidth-intensive, next-gen IIoT applications.

Kinetic mesh is flexible. Each node can maintain multiple simultaneous connections—none must break for new ones to be made. Peer-to-peer (P2P) networking software runs on every node to dynamically direct traffic via the fastest available path at that moment.

The network self-optimizes as nodes move and conditions change, reacting to changes in network topology, network load, and external environmental conditions to keep operators constantly connected to, and in control of, high-value assets on the move. If a path is blocked or interference is identified, instead of dropping connections, information instantly is redirected over the best available paths, creating total mobility and communications agility.

Kinetic mesh offers reliability. Multi-transceiver redundancy eliminates any single point of failure, and multiple radio frequencies open redundant traffic pathways, for mission-critical reliability. With hundreds of potential connections available, the network avoids interference, signal blockage, or congestion. Built-in redundancy ensures consistently high network availability for 24/7/365 operations.

Kinetic mesh is highly scalable, allowing manufacturers to create or augment network infrastructure ad hoc. Nodes can be deployed anywhere, on any asset, to extend or enhance operational coverage. Expansion does not cripple connectivity. Rather, kinetic mesh strengthens as it grows. Each additional node establishes new pathways for data transmission, making the network more resilient as it expands, without compromising speed or performance.

These four qualities—bandwidth and speed, flexibility, reliability, and scalability—create a network equipped to handle both today’s demands and those of the future—one deployed and scalable to hundreds of nodes in device-intensive IIoT environments. [subhead]

A network for the future

As industrial companies consider what network is right for them, now and in the future, it’s important to implement a broadband layer that offers autonomous adaptability.

LTE, PtP/PtMP, or fiber are options, but if a network experiences congestion or infrastructure outages, it’s harder to keep data flowing for device message delivery. Kinetic mesh used as the broadband layer overcomes these challenges.

IIoT needs a network that functions in dynamic, diverse environments, connecting people to people, people to things, and things to things—whether mobile, fixed, or both—interchangeably to deliver real-time intelligence. Kinetic mesh is architected with autonomous adaptability, to redirect routes and take new paths that ensure continuous data flow. It is an ideal solution for industrial companies to consider when embarking on the journey toward IIoT.

Todd Rigby is IIoT strategist and director of sales for Rajant Corp.

This article appears in the IIoT for Engineers supplement for Control Engineering and Plant Engineering

See other articles from the supplement below.