In Industrial IoT, network Quality-of-Service (QoS) is hands-down a top priority. Because industrial applications are often mission-critical, failing to get the message through, particularly in times of emergency, can result in costly and even disastrous consequences. Think of situations like material tanks going empty, workers falling from heights or a spike of flammable gases in the atmosphere.

To ensure important data is accessible when needed the most, QoS of the communication network is paramount. A primary QoS indicator is packet error rate (PER) which signifies the percentage of failed transmissions out of total sent messages. In industrial applications, a PER of less than one percent is typically demanded. This study will prove that MYTHINGS delivers significantly higher interference resilience than LoRa technology.

Quality-of-Service in LPWAN

Given their unique range, power and cost advantages, Low Power Wide Area Networks (LPWAN) are expected to answer the growing demand for low-power, reliable industrial M2M communications. That being said, QoS remains a challenge for most LPWAN solutions. This is mainly due to two reasons – their operations in the license-free spectrum and the use of simple asynchronous communication, typically pure ALOHA (a node accesses the channel and sends a message whenever there is data to send). While bringing significant power benefits, uncoordinated transmissions in asynchronous networks greatly increase the chance of packet collisions and data loss. As wireless IoT deployments and radio traffic in the license-free sub-GHz bands rapidly grow, legacy LPWANs potentially come with serious QoS and scalability challenges caused by co-channel interference.

Several mitigation mechanisms are available as add-on deployment options in the Medium Access Control (MAC) layer to reduce packet collisions and improve QoS in LPWAN. One is the acknowledgment of received messages, in which a retransmission attempt is triggered if no packet acknowledgment is present. Another is the Listen-Before-Talk function wherein a node senses ongoing transmission in the radio environment before sending a message.

The problem with these mitigation mechanisms is their persistent trade-off on battery life. They introduce extra communication overhead that considerably increases on-air time and power consumption of every message, not to mention higher complexity and cost of the transceiver design. Adding acknowledgement also raises the chance of failed messages, since a transmitting base station can’t listen for incoming messages. As such, mitigation mechanisms are often bypassed in real-world LPWAN deployments, especially when long battery life is desired. When retransmission is absent, Packet Error Rate becomes the key parameter to gauge QoS in LPWAN.

A Comparative Study of MYTHINGS vs LoRa Technology

To resolve the trade-off between QoS and power efficiency, an LPWAN’s modulation scheme and its underlying physical layer technology must be purpose-built for interference immunity. Most, if not all LPWAN technologies swear by their reliable performance in the crowded license-free spectrum. But, it remains a big question to what extent the statement holds true and how different technologies compare. To accurately picture the difference in interference immunity among different LPWAN solutions, an impartial study has been conducted to evaluate the performance of MYTHINGS vs LoRa technology in the same IIoT-equivalent scenario.

As a widely adopted LPWAN solution, LoRa technology employs Chirp Spread Spectrum (CSS) modulation scheme that claims to provide robustness against interference and multipath conditions. On the other hand, MYTHINGS is an emerging wireless connectivity software platform that implements TS-UNB – a unique LPWAN technology recognized by ETSI for its interference resilience and scalability.

Both MYTHINGS and LoRa networks operate in the sub-GHz frequency bands and employ pure ALOHA. To ensure a fair comparison, in this study, the LoRa system is set to Spreading Factor 12 which offers the highest range and interference immunity.

Download Now: MYTHINGS vs LoRa Comparative Study

The following infographic encapsulates key information on the test setup, execution and results.

Takeaways

The study has shown that not all LPWANs are created equal and network QoS under interference can drastically vary from one technology to another. While MYTHINGS could quickly zero out packet loss under heavy interference conditions, packet loss on the LoRa network remained considerably above the 1% permissible threshold. High PER signifies poor QoS and a great unpredictability in message reception. In mission-critical IIoT applications, such a network can fail exactly when you need it the most. A solution purpose-built for interference resilience like MYTHINGS, provides you with a robust and future-proof IoT architecture that enables seamless network expansion while guaranteeing optimal performance. LoRa Technology vs. MYTHINGS technology report.

Driven by pervasive, battery-powered sensor networks that capture data at unprecedented granularity, the Internet of Things (IoT) is reshaping the industrial connectivity landscape. From remote monitoring and energy management to worker safety and environmental sensing, Industrial IoT (IIoT) applications demand new wireless infrastructure that satisfies critical requirements in terms of power consumption, scalability, mobility, and cost – without compromising carrier-grade reliability.

In our newly issued IIoT Survival Guide, we take a look at the two leading options for IIoT edge connectivity – low-power mesh solutions based on the IEEE 802.15.4 standard and low-power wide area networks (LPWANs). While both are designed to support battery-operated sensor networks, the two approaches vary greatly in network criteria. By understanding their major differences, system designers can decide which wireless option is a better match for their architecture and use cases.

Download the full guide here

A network topology defines the way various components communicate with each other within an IoT network. Topologies can vary greatly in security, power consumption, cost, and complexity. Before choosing and implementing a communication technology, it is important to first understand which topology is most relevant to your IoT applications and requirements. In this blog, we compare mesh vs star topology – the two most common architecture types for IoT wireless networking.

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Mesh Topology

In mesh networks, a message hops from one device to another in order to reach its destination (e.g. a gateway). A sensor node, serves as both an endpoint that captures and transmits their own data as well as a repeater that relays data from other nodes. In a partial mesh network, only selected nodes have the repeater/relaying function and are connected with more than one other node, while in a full mesh network, all nodes are homogeneous and fully interconnected to each other.

Mesh topology is widely employed to extend the coverage of short-range wireless technologies such as Zigbee, Z-Wave, WirelessHART. Most mesh networks have a self-healing capability as data can be re-routed using another path if one repeater node fails, thereby enhancing robustness.

If enough repeaters are installed, you can cover large areas like an entire industry campus or a commercial building using mesh configuration. Nevertheless, since the range between two nodes is very short in nature, the number of required repeaters increases rapidly, making these networks very expensive to install. In many cases, extra sensor nodes must be added, not to capture data, but simply to attain the desired coverage.

Redundant device density and excessive numbers of connections significantly complicate network setup, management and maintenance activities. Complexity greatly hampers scalability and despite low transmit power, the relaying nature of mesh networks imposes very high power consumption. Nodes must constantly be “awake” and “listen” to whether a message needs to be relayed. High relaying traffic through one node can also quickly drain its battery.

Another major concern over mesh networks is their vulnerability to security attacks. If a single repeater is breached, the entire network collapses. The larger your IoT network, the more repeaters – or better said – the more possible points of attack. When it comes to full mesh networks where all nodes act as the repeater, you may want to think twice before installing one.

Star topology

An alternative approach to wireless IoT networking is star topology whereby all sensor nodes communicate to a central hub/access point (i.e. a gateway). Technical design of the central hub is much more sophisticated to handle huge amounts of data flowing to it.

Thanks to one-hop, point-to-point connection, star topology is much simpler and less expensive to implement compared to mesh topology. Network security also increases, as endpoints operate independently of each other; if a node is attacked, the rest of your network still remains intact.

The primary disadvantage of star topology is that the network footprint is limited to the maximum transmission range between devices and the gateway. However, choosing the right communication technology can help overcome this problem. For example, a Low-Power Wide Area Network (LPWAN) with an extensive range of over 10 km line-of-sight will enable vast coverage when deployed in star topology.

LPWAN star networks are optimized for minimal power consumption and can secure years of battery life on the sensor side. Unlike mesh topology, nodes are not required to be continuously “awake” to listen and relay data from other nodes. Outside of transmission time, they can fall into “sleep mode,” consuming almost no power.

So which topology is the right one for you?

The answer is very simple: It all comes down to your IoT applications.

For example, Zigbee, Wi-Fi or Bluetooth mesh networks can be a great option for applications in the consumer marketplace. Smart home use cases such as HVAC and lighting automation often require smaller coverage areas with a limited number of endpoints positioned close to each other.

Mesh topology is also a viable solution to extend the footprint of legacy Wi-Fi networks – available in literally every single house nowadays – without exploding costs or involving sophisticated network management. High bandwidth usage in many consumers applications like video calls and streaming, voice control, etc. further makes Wi-Fi mesh most feasible if you’re looking for one integrated home network.

On the other hand, if you want to connect hundreds or thousands of sensors distributed over geographically dispersed campuses and facilities like factories, mines, oilfields or commercial buildings, LPWAN using star topology is the better choice. It provides a reliable, cost-effective and easy to deploy and manage solution. Configuring and optimizing mesh networks, on the contrary, can be an extremely daunting task in this case.

Still wondering which combination of network topology and communication technology best suits your needs? Visit our blog on 6 Leading Types of IoT Wireless Tech and Their Best Use Cases.