Application Note

Reliable M2M Communication And Networking Technology Connects Wastewater Facilities

Source: FreeWave Technologies, Inc.

By Paul Mercier, Regional Manager for OEM, Utility and Energy Markets, FreeWave Technologies, Inc.

As the world becomes increasingly connected, the integration of smart devices and tools, such as sensors, process control devices, security cameras, for example, have increased the need for well-established, secure machine-to-machine (M2M) communication and networking solutions. Many companies depend on effective communication technologies to reduce overhead costs and improve their bottom lines. Today, however, it’s not just important to retrieve and review the data gathered by these tools. Companies are now taking a closer look at their data and focusing more on how to leverage real-time statistics to make quick and informed decisions for improvements to their operations and sometimes for increased safety and service measures. Increasingly, technologies are doing the decision-making for us and it is vital to leverage dependable solutions that match our utility needs the best.

With the proliferation of M2M capabilities enabling critical applications within the water/wastewater market, operators and management have a clear view of what is occurring within their systems, from tank levels and temperatures to pressures and pump controls. There are good reasons why M2M solutions are growing for this industry and others. There are attractive benefits for implementation such as the improvements to communication technologies that now allow for control and monitoring of a water/wastewater facility’s SCADA system from a distance. Wells, lift stations, pump houses, storage tanks and other endpoints within a system can be brought to an operator’s fingertips without the costly expense of running wire or fiber to these locations. With M2M communications, extra input/output (I/O) products offer flexibility and can be expanded as needed. Wireless M2M communications also allow wastewater personnel the flexibility to integrate new locations, such as treatment facilities or substations, and expand new applications while maintaining them in the existing SCADA system infrastructure without the concern of any preexisting communication network technologies.

Enabling M2M applications within the water/wastewater market is an important objective of utilities today, but how can operators and management teams leverage the best possible solution(s) for their facilities? Before reviewing the M2M communication technologies available today, it is imperative to review two important success factors that need to be addressed with M2M communication technology solutions: security and reliability.

Many would argue that water/wastewater operations are only as reliable and secure as the technology serving the critical functions within the facilities itself. While reliability and security are completely separate success factors, often these considerations play into one another. Overall, decision-makers must consider some important questions in regards to reliability and security features of M2M communication and networking solutions before ever selecting a technology. For example:

  • What is the M2M communications technology controlling or automating? Is it essential that it operates without failure?
  • What data is being collected and/or transmitted with this technology? Is it time-sensitive and/or mission-critical?
  • What technology solutions have a proven track record for the applications being served?
  • What external factors might impact the reliable transmission and receipt of critical data from one point to another?
  • How does this M2M communications technology address challenges such as data encryption, network access control and signal interference?
  • Do we need this technology solution to be fail-safe, in order to prevent or eliminate catastrophic damage from occurring?
  • Is cyber security or physical security a greater concern for this deployment?

Proprietary communication technologies and devices (especially when they offer many “knobs” and configuration options to create private, user defined networks) actually offer a higher degree of security. But even those technologies are subject to security and reliability threats. Therefore, network access control is one of the most important security features for M2M communication and networking technology in order to prevent unauthorized access and intrusion. A proven communication network security strategy should go even further and protect data “in transit” as well. Even if an unauthorized device manages to gain access to the M2M communication network, it isn’t necessarily gaining access to the actual data without passing yet another layer of security. Last, but not least, a communication network security strategy needs to address and implement policies that serve as safeguards, which make it difficult to circumvent security measures and limit the potential impact of a security breach. When reviewing the technology options below, it is imperative to keep security policies in mind to achieve a higher level of system reliability.

M2M Communication and Networking Technology Options

As more sophisticated ways of remotely operating and monitoring machinery in the field continue to emerge in the utility industries, more M2M communications technology solutions, especially wireless, become available. As previously stated, there is never a “one size fits all” solution for the entire wastewater market, and sometimes a combination of M2M communication technologies are viable options for serving critical functions within the wastewater utility. Therefore, it is important to understand that every technology has both advantages and disadvantages. Some of the common M2M communication technologies used today include:

Frequency Hopping Spread Spectrum (unlicensed private radios)

Some of the most traditional and widely used M2M communication solutions for the past 20 years have been Frequency Hopping Spread Spectrum (FHSS) radio technologies for private radio network solutions running in unlicensed spectrums. These wireless technologies offer highly reliable and secure data transmission with low latencies, desirable range and throughput rates. This enables real-time monitoring and control of automation equipment and the ability to transmit and receive data over long distances, sometimes up to 60 miles Line of Sight (LOS). Wireless data communication equipment providers have taken leaps forward for customers who need industrial grade serial and Ethernet radios that operate in harsh, challenging and congested radio frequency (RF) environments.

As with all technologies, FHSS radios have some potential limitations. A real limitation is that they do require an infrastructure that is LOS in nature. They are also more susceptible to interference in heavily wooded areas than some other competing technologies. However, this deterrent can be easily overcome with proper planning, network design and path studies, which all should be provided by the manufacturer or systems integrator. There are additional concerns about “frequency saturation” in areas where there are many unlicensed radios operating. Others are simply concerned about these radios operating in a shared spectrum (for example 902-928 MHz). On the other hand, FHSS spread spectrum radios also have many advantages. They provide for much higher throughput than licensed systems. They do not require a license, which adds to administrative costs and headaches. They are very flexible in many ways.  For instance, by using repeaters, the achievable network range is unlimited. Wireless FHSS communication networks that have been used and proven by 100’s of utilities as a reliable solution for many years.  These type of radios are relatively easy to install, and, if done properly, can offer the same reliability and security measures as wired systems and at a much lower cost. Because of the strengths of FHSS wireless data radios, utility decision makers are increasingly implementing a wireless communication system into their wastewater systems.

Fixed Frequency (licensed private radios)

Licensed wireless radio technologies can be deployed in a variety of frequencies nearly anywhere in the world, giving them flexibility for any installation. The radios can be very tolerant of Mother Nature’s challenges, especially in the lower frequencies. At 400 MHz or 200 MHz, for example, the wireless radios will penetrate wooded areas better than 900 MHz licensed and FHSS. Furthermore, using a fixed frequency radio provides the user an opportunity to “own” that frequency in the geography where they hold the license with the FCC (in the U.S.) or another spectrum holder. This is because the user owns the frequency within that specific area and will not be faced with interference from another user.

Disadvantages of licensed radios include lower bandwidth challenges. In some frequencies, the channel spacing can be as limited as 6.25 kHz and no more than 25 kHz. Even at 25 kHz, most radios will only deliver 19.2 Kbps. When Ethernet is layered into the equation, the throughput also takes an overhead hit. Additionally, while owning the spectrum in an area is an advantage, it also can be a disadvantage because users need to take the necessary steps to acquire a license from the FCC or another spectrum holder. In some frequencies and geography combinations the licenses for a required throughput are not available. In other cases, there might be plenty of spectrums available though it might also be prohibitively expensive.


Satellite systems have significant broadband capabilities and tend to be both reliable and ideal for long-range backhaul applications. While it is costly to deploy, one big advantage for satellite systems is that they can be deployed almost anywhere in the world. They are, however, a non-private system with shared bandwidth for all users. Plus, regular system maintenance and repairs in the event of an outage are not in the control of the user. Only the system provider has access to rectify outage events, do maintenance or add to system throughput with more infrastructures. Satellites also incur monthly recurring costs to the user, which needs to be addressed in the cost/benefit analysis when using this solution.


Leveraging a cellular network infrastructure has several advantages over other technologies. The biggest advantage is that there is no need for the utility to craft a tower infrastructure plan. For the most part, the technician simply turns on the cell modem and a link is created – where there is cell coverage. Furthermore, the actual network design and implementation is far simpler than other competing technology systems. Disadvantages include the monthly charges and the fact that this is a public network within a shared spectrum. The utility has no real control over system utilization and especially not when there is an outage in the cell network. There are many non-urban areas that have low or no coverage at all and even in urban areas, service commitments notwithstanding, there can be coverage problems. Latency in cellular systems is often discussed as a potential problem for utility applications. With utilities and agencies recommending that latencies for any one-way communication are equal to or less than 50 milliseconds or, in some cases, less than 10 milliseconds, the utility has to have confidence that the communication technology selected will reliably perform at this level.

Copper or Fiber Wiring

Copper- or fiber-wired solutions can provide much more throughput than most wireless M2M communication technologies. Furthermore, these wired solutions are understandably perceived as more reliable and secure compared to wireless. However, the cost to deploy these solutions can be significant, especially for wired solutions spanning long distances. Oftentimes, the cost associated with these types of wired solutions make either of these technologies impractical due to cost and other issues (e.g., trenching, right of way challenges, etc.). If cost and right of way are not issues for the utility, these options, especially fiber, are very compelling choices. No other M2M communication technology discussed will provide the throughput speeds and reliable data transfer of fiber. Just like all M2M communication technology, it is not maintenance free, but that is just another variable in the total cost of ownership equation.

Additional Considerations

The days of building large, single technology networks may likely be behind us. Data and security demands at various levels of a large communication network are changing the game. There are options that allow utility decision-makers to consider better manageability, expandability, cost and speed, depending on the particular M2M application or service requirements. Hybrid networks can mix and match different technologies to leverage certain strengths and limit certain weaknesses of any given technology solution.

Finally, in considering these technology options and more, it is important to understand that critical infrastructure needs to be adaptable in order to serve future generations. This concept obviously also applies to the technology within the water/wastewater market. The more flexible and adaptable a technology solution is today, the more it will be used in the future, which is why tried and true wireless M2M communication and networking solutions are likely to be the technology of choice going forward.


At the end of the day, effective M2M communication and networking technology keeps utility operators informed on the health of their facilities, enables smooth operations and ensures proper monitoring and control of their devices. By deploying the appropriate technology to address key M2M applications, operators can have critical data delivered to their fingertips on a real-time basis. This allows them to constantly monitor and react to problems in a timely manner, whether it’s unauthorized tank access, a pump malfunction or any other operational challenge. With all of the critical functions and operations within a wastewater system, it is no wonder why utility decision-makers are inundated with numerous technology options for serving critical M2M applications. While the necessary task of selecting communication and networking technologies can be time-consuming and challenging, there is no denying the fact that both wired and wireless options provide the connections needed to automate, control and monitor the water/wastewater facility. In the long term, investment in a reliable and secure M2M communication network not only saves costs, but can prevent catastrophic accidents from occurring that result from failing equipment or technology. When used properly, these technology solutions can pinpoint the problem immediately.