The Public vs. Private Network Battle: Creating Connectivity for the MC-IoT Boom
- Jan 4, 2019 8:45 pm GMT
- 700 views
Critical infrastructure is the backbone of our nation's society, providing essential services that enable comfort, security, and livability for Americans. For several decades, critical entities, such as electric utilities, oil & gas and others, have relied on their own telecommunications networks. These privately owned and maintained networks have been used to manage day-to-day operations and to coordinate emergency services in times of crisis. Now, however, mission critical entities are being pressured to either increase data capacity of these networks or shift to public commercial networks to accommodate the push for Mission Critical Internet of Things (MC-IoT) connectivity.
For mission critical entities, public commercial networks do not provide the security or reliability that’s necessary for Supervisory Control And Data Acquisition (SCADA) applications. Simultaneously, their own private networks face capacity challenges with the increased amount of data shared over the MC-IoT and access to additional spectrum to expand network capacity is limited by the FCC. To find a single solution that allows for the continued use of private networks and which meets the needs for availability, reliability, capacity and security, utilities and other mission critical entities have rallied behind a new wireless broadband standard known as IEEE 802.16s.
Public Networks Aren’t Suitable for Utilities’ Growing Needs
Mission critical entities require wireless network connectivity to increase efficiency and support automation for remote operations. Utilities, in particular, need to be able to push and pull information back from the grid’s edge, managing a host of remote MC-IoT technologies including substations and motor operated switches in addition to downline distribution devices that previously didn’t need connectivity such as voltage regulators, reclosers, and capacitor banks. As MC-IoT emerges, public commercial cellular network providers including AT&T, Verizon, T-Mobile and Sprint are pushing their solutions for smart applications with the grid and other industrial uses. However, these public networks are built to support consumer traffic demands, not the needs of mission critical users.
For example, commercial cellular networks are not designed to withstand natural disasters and long periods of time without power. While cellular sites may have battery plants with a four or eight-hour capacity, very few have onsite generators and fuel tanks designed to last multiple days or even weeks which is what mission critical industries private communications systems are designed for.
The very real impact of natural disasters has made clear, in recent years, 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. The impact report published by the Federal Communication Commission (available at fcc.gov), shows that heavy rain and high-speed winds led to cellular outages scattered throughout the area, with some counties experiencing coverage losses as high as 94.7%.
The local electric utility, however, that 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 (SCADA), maintained 100% communication availability during the entirety of Harvey. They had only one outage, caused by extensive flooding, at a single substation.
It’s important to note that cell site outages are often 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, any communication network intended for use during power outages simply has to have a reliable source of backup power.
The case for private networks
Mission critical organizations have relied on their own networks for decades because they deal with operating requirements that are more stringent than in other industries. Utilities have had private voice communication networks in place for their existing land mobile radio service and narrowband data communications to their substations and transmission grid. The challenge is that data requirements are increasing exponentially, and these narrowband private data networks don’t have the capacity to accommodate the increasing requirements. However, commercial cellular networks are not designed to meet the needs of mission critical industries. They are designed to meet the needs of the consumer market place and cannot meet the main criteria needed for mission critical communications.
By running their own networks, mission-critical services can be certain they have the four things needed to remain responsive and effective in times of emergency: reliability, availability, latency, and security.
Communication with personnel and devices needs to go through, without interference, even if transmission and reception take place in rural or remote areas.
Emergency services cannot afford network down time. The goal of 100% network availability may only be attainable 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 typically a level of service commercial carriers are willing to provide.
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 switching a power line, controlling a circuit breaker, or sending a stop command to an out-of-control train, the signal needs to be transmitted in a fraction of a second, but commercial networks rarely, if ever, support latency rates this low.
Safety and protection are of primary importance, for employees as well as the public, since extreme harm can result if a mission-critical infrastructure is hacked in any way. Access to the network needs to be restricted, to ensure only authorized personnel go online, and data transmissions need to be encrypted, to prevent tampering, theft, or, worse yet, acts of sabotage or terrorism.
The Introduction of a new standard for utilities
One solution that has proven itself to be better suited for MC-IoT applications, particularly those for electric utilities, is the use of private licensed wireless networks built to a new standard titled IEEE 802.16s.
Licensed spectrum provides a higher degree of security, safety and control by limiting who has access to the network and establishing an air gap between the private network and public networks. Private networks that leverage licensed spectrum also ensure capacity and reliability as they are owned and operated entirely by the entity that deploys it. The network can then be built to ensure bandwidth availability to support data flow and speeds. There is a challenge however as licensed spectrum in channels where current technologies can provide the appropriate bandwidth is limited due to larger public carriers cannibalizing the space.
IEEE 802.16s establishes a framework for utilities to access technologies that work in a broader range of available, licensed channel sizes to support capacity and bandwidth needs. Developed with assistance from the Electric Power Research Institute (EPRI) and the Utility Technology Council (UTC) along with utilities and key vendors, IEEE 802.16s supports channel sizes between 100 kHz and 1.25 MHz and can be deployed in any frequency band.
The standard also supports a multi-vendor ecosystem, providing a framework for multiple vendors to build technologies to its requirements. This eliminates reliance on proprietary technologies and ensures longevity in the event that a vendor discontinues a product or goes out of business.
What utilities can expect for the future
As the digital age continues to advance and become widespread, more mission critical industries will continue to deploy technologies to improve security and operational effectiveness. These industries need to have access to spectrum to deploy and operate private, mission critical networks upon which our nation relies.
The incorporation of MC-IoT and private wireless networks builds a new model for industrial applications, establishing the ultimate goal of a secure, ongoing, multi-vendor eco-system across large, global critical infrastructure end markets – making standards-based solutions even more crucial for utilities throughout the nation.