The network the oil & gas industry needs

The case for private wireless, mission-critical communications networks.

By Kathy Nelson, P.E. July 28, 2019

For several decades, the oil & gas industry relied on its own telecommunications networks. These privately owned, privately maintained networks are used to manage day-to-day operations and coordinate emergency services in times of crisis.

Many of these networks are mission-critical and use portions of the wireless spectrum that are either unavailable to other users or unwanted by other industries. Historically, the FCC has made some narrowband spectrum available through spectrum coordinators to allow geographic reuse without interference. Increasingly, these low data capacity networks struggle to keep up with Internet of Things (IoT) technology.

Additionally, the use of private, uncrowded portions of spectrum was employed because mission-critical tasks like providing power, producing and providing energy to the public, protecting citizens and responding to disasters needed clear, reliable channels of communication to be effective. In recent years, however, these mission-critical networks evolved to incorporate edge computing and IoT technologies. Deployment of new services has caused an exponential increase in data communications and is straining the capacity of many in-place infrastructures. At the same time, the ongoing need to implement and maintain security, both cyber and physical, has added to mission-critical networks’ data requirements.

More modernization, less interference

Many of today’s mission-critical networks face a two-fold challenge. First, there is the need to modernize. Present-day requirements for real-time data, sophisticated control and monitoring closer to the network edge and high-level security place new demands on infrastructure and often exceed what narrowband networks can support.

Second is the need to ensure quality communications. Some portions of the licensed spectrum—those used by first responders, for example—remain dedicated solely to their use and are therefore clear from interference. Other portions—such as those used in the oil & gas industry—are more congested due to changes in allocation. Spectrum portions where mission-critical services traditionally operate either are being reallocated to commercial providers or made accessible to other users. As a result, they experience increased interference.

Do private networks meet the need?

As mission-critical services address modernization challenges and are forced by the spectrum crunch to seek alternatives with less signal interference, pressure increases to make use of public cellular networks because they are available. A commercial network for mission-critical services lowers capital costs, but all other decisions involving a network are left up to the service provider including how spectrum is allocated, the schedule for technology upgrades and maintenance, how to ensure availability and so on.

While commercial network providers are eager to gain business in mission-critical services and may structure their offerings to suit those needs, their long-standing commitments influence their policies. For example, cellular technology supports prioritization which lets network operators give priority to mission-critical communications, but today’s commercial providers don’t make use of this capability. Thus, consumer-driven demand for things like streaming media take bandwidth away from mission-critical services when it’s needed most.

Also, when working with a public cellular provider, commercial networks typically don’t provide the level of performance necessary to support mission-critical applications.

Stringent requirements

The oil & gas industry cannot compromise when it comes to connectivity. They deal with more stringent operating requirements than other industries and their business continuity drivers require a committed network that is stable and predictable.

By running their own networks, oil & gas operators and other mission-critical services can be certain they have the four things needed to remain responsive and effective in emergencies: reliability, availability, latency and security.

Reliability: Communication with personnel and devices needs to go through, without interference, even if transmission and reception take place in rural or remote areas.

Availability: Critical networks cannot afford down time. The goal of 100% network availability may be attainable only in theory, but a standard for today’s mission-critical networks is 99.999% availability, which equates to five minutes of downtime per year. Few, if any, commercial networks offer this level of availability. Even 99.99% availability, which equates to 52 minutes of downtime per year, is not a level of service commercial carriers and their publicly available, consumer-focused network products provide.

Latency: Control and signaling communications sent to and from remote devices must be delivered without delay, at extremely low latency rates. When performing tasks such as remotely controlling oil or gas flow and equipment, the signal needs to be transmitted in a fraction of a second, but commercial networks can never guarantee latency rates this low.

Security: Safety and protection are of primary importance for employees as well as the public, since extreme harm can result if oil and gas infrastructure is hacked in any way. Access to the network needs to be restricted to ensure only authorized personnel can get into the network, and data transmissions need to be encrypted, to prevent tampering, theft, or, worse yet, acts of sabotage or terrorism.

Commercial cellular falls short

Commercial public cellular networks don’t offer the levels of reliability, availability, latency and security that mission-critical services require. Meant primarily for consumer markets, commercial cellular networks focus most their resources on urban areas, where consumers use high-bandwidth connections.

While public cellular networks can deal with short-term blackouts and other service interruptions, they’re not prepared to the same extent that mission-critical networks are. Where a commercial base station might have backup batteries onsite for four to eight hours of operation, or be able to connect to a backup power source, mission-critical networks tend to have onsite generators ready to run for days at a time without a service call. Many sites have redundant backhaul paths or rings to improve data accessibility to the site during emergencies and put redundant radio hardware in place to ensure continuity.

Real-world failures

Natural disasters in recent years have made clear the risks of relying on public cellular networks for mission-critical services. In August 2017, when Tropical Storm Harvey made landfall in Texas, 55 counties were declared disaster areas. Heavy rain and high-speed winds led to cellular outages throughout the area. Some counties experienced near 95% coverage losses.

The local utility, however, which owns, operates and maintains a private land mobile radio system, as well as a private network for mission-critical communications for monitoring and controlling devices, including SCADA, maintained 100% communication availability during the entirety of Harvey. It had only one outage, caused by extensive flooding, at a single substation.

Note that cell site outages often are due to power outages. Any critical infrastructure service that relies on a public cellular network for communications will fail to respond during blackouts and other emergencies, because having a cell site go down means communication with personnel and devices in the field goes dark. That is, a communication network intended for use during power outages has to have a reliable source of backup power.

The private licensed alternative

Discouraged by the prospect of sharing spectrum with the general public, mission-critical services are expanding and enhancing private networks to gain the connectivity and coverage needed.

Private networks operate in FCC-protected licensed spectrum to maintain control, security and reliability. However, mission-critical services need access to their own private, licensed spectrum, for use within a given band and geographic area. Licensing ensures wireless operators don’t interfere with each other’s transmissions and gives mission-critical services an operating environment that is free of interference associated with unlicensed channels.

Need for standardization

While private networks are critical to mission-critical industries, most operators, including oil & gas, do not have access to enough radio frequency (RF) spectrum to deploy standard technologies such as LTE or IEEE 802.16, the two most common wireless technologies. Additionally, standards such as LTE are for the consumer industries. Oil & gas companies are forced to install proprietary communications networks, which puts them at risk if the manufacturer goes out of business or discontinues a product line. However, in 2017, a narrower channel standard technology was ratified and published by the IEEE.

IEEE 802.16s was a grassroots effort launched because electric utilities and other mission-critical industries were looking for a standard technology to use in the narrow channel bands they access, typically purchased on the secondary market such as the 700 MHz A band, 217 – 219 MHz, 1.4 GHz and others. These spectrum bands do not have enough bandwidth to support other standard technologies. LTE requires a minimum of 1.4 MHz and IEEE 802.16 a minimum of 1.25 MHz of bandwidth.

The IEEE 802.16s standard is designed specifically for the mission-critical private broadband wireless market. It provides multimegabit throughput using relatively narrow channel size (between 100 kHz to 1.20 MHz) and long range (e.g., 25 miles and beyond) to minimize spectrum acquisition and network infrastructure cost.

IEEE 802.16s is optimized for mission-critical remote-control applications, not the consumer market. Many mission-critical applications such as SCADA require more data to go from the remote devices, such as a well pump head, to a master device. This is a reverse asymmetrical data flow and is nearly opposite to the consumer market, which is heavily driven by data that goes from the network to the remote device. IEEE 802.16s addresses this by adopting time division duplex (TDD) with a downlink to uplink traffic ratio up to 1:10.

FDD versus TDD

LTE and several proprietary technologies are based on FDD since spectrum has historically been paired. To understand the difference between FDD and TDD, think of FDD as a freeway where there are the same number of traffic lanes going into and out of a city. During morning rush hour, all the traffic lanes going into the city are clogged and traffic is moving slower due to congestion, while the traffic lanes going out of the city are mostly empty. It would be more effective if some of those lanes could be configured so that more of them could go into the city because there is more traffic in that direction. TDD allows for that “traffic lane” configuration. You can choose how many lanes move in each direction, making more efficient use of the RF spectrum. This is important when RF spectrum is limited and is the basis of IEEE 802.16 and IEEE 802.16s.

While IEEE 802.16 is a good base for an efficient wireless technology, changes were needed to reduce the overhead so more user data could be transmitted. The standard can be reverse asymmetrical, for more throughput upstream than downstream, which is how most mission-critical systems function. Moreover, It can be symmetrical or asymmetrical, depending on system requirements. In addition, the standard has been made more efficient.

As oil & gas networks move to the network edge, communications network capabilities need to increase. This highly efficient, narrower channel standard enables critical industries to deploy mission-critical applications on private, licensed, secure wireless communications networks.

These communications networks can manage a variety of oil & gas operations including drill rigs, pressure gauges, rectifiers, tank monitors and more. In addition to controlling operations such as starting or stopping pumps, these networks provide real-time monitoring of assets, identifying and minimizing potential equipment failure from wear and tear or communication disruptions. Operators can improve field productivity and reduce energy waste and machine wear and tear.

Chevron has tested IEEE 802.16s radios in the 1.4 GHz band. It looks to replace point-to-point copper circuits the telephone company is discontinuing and also at point-to-multipoint options for well head monitoring and control. Using this private wireless standard a master radio can talk to remote radios more than 20 miles away.

“As we look to the next generation of 1.4 GHz gear, the prospects of having an industry standard as an option are exciting, particularly when that new standard infuses a lot of new technology that allows for more efficient use of the spectrum,” said Fredrick Smith, a Chevron infrastructure architect.

The better choice

A private, licensed, standard technology approach to network operation offers greater control over availability and security of critical services and provides a foundation for the smart applications that oil & gas demand.

Perhaps even more important, though, is the fact that private licensed networks let mission-critical services deliver the benefits industry requires. By running mission-critical services on private licensed networks, the oil & gas industry will remain safer and more resilient in difficult times.

Original content can be found at Oil and Gas Engineering.

Author Bio: Kathy Nelson, P.E., is director, Technical Product Marketing and Industry Relations at Ondas Networks.