The American Public Power Association and several other trade groups are voicing concerns over a Federal Communications Commission (FCC) proposal to open the 6 GHz spectrum band to unlicensed use, saying that they have significant concerns that the proposal could threaten the integrity of their mission-critical communications networks.
The May 15 letter was sent to Ajit Pai, Chairman of the FCC, by the American Public Power Association, National Rural Electric Cooperative Association, Edison Electric Institute, Utilities Technology Council, and American Water Works Association.
The FCC is seeking comments on its proposal to open the critical 6 GHz spectrum band to unlicensed use.
“We write to urge you and your colleagues to protect the licensed, mission-critical communications systems in the 6 GHz band that are used to monitor and support the reliable delivery of electricity and other critical utility services,” the groups said in their letter to Pai. “Unfortunately, the mitigation measures proposed are not enough to protect these highly critical systems, and therefore, we have deep concerns with this proceeding.”
The groups noted that the critical industries they represent own and operate massive infrastructure to deliver life-sustaining services for all aspects of the economy, including technology and telecommunications. This infrastructure consists of power plants, interstate and intrastate electricity lines, interstate and intrastate water and gas pipelines, control centers, and substations, among others.
“Because electricity travels at the speed of light, balancing the supply and demand of electricity requires intense planning, careful coordination, and robust and redundant infrastructure. Additionally, gas and water pipelines must be continuously monitored for safety and reliability,” the letter said.
To support the reliable delivery of these services on a real-time basis, the memberships of the groups deploy a sophisticated array of private telecommunications networks throughout their service territories.
“Our collective membership of critical-infrastructure industries (CII) delivers the most critical commodities necessary for sustaining life and public health—water, electricity, and natural gas,” the groups pointed out.
CII communications networks consist of wireline and wireless technologies. While wireline services can provide faster and more reliable communications, wireline can be cost prohibitive in remote locations. “Therefore, our collective members must rely on wireless networks for numerous mission-critical communications needs.”
The groups said that these communications networks provide critical situational awareness, underpin safety functions, and enable crews to safely repair and restore services after storms. “Additionally, for electric utilities, these networks are essential for our members to meet and exceed the stringent electric reliability requirements enforced by the federal government. These networks also support the greater deployment of distributed energy resources such as solar or battery storage, smart meters, and other technologies to enable grid modernization.”
Hundreds of CII entities have licenses in the 6 GHz band for their microwave communications. Licensed spectrum offers the reliability and protection from interference that these networks require. “Due to the criticality of these networks, electric utilities cannot tolerate even the slightest risk that these communications systems could be degraded, as diminished situational awareness can result in degraded reliability,” the letter noted.
With the FCC considering expanding access to the 6 GHz band for unlicensed use, “we have significant concerns that this proposal will threaten the integrity of our mission-critical communications networks.”
The groups strongly encouraged the FCC to weigh the advantages of expanding access to the 6 GHz band with the potential negative impact this could have on critical infrastructure networks.
As an example, the groups noted that electric utilities use the 6 GHz band for teleprotection, a system of devices that relay information and monitor the health and status of power lines. If a line is experiencing a problem or fault, teleprotection systems automatically take actions to prevent the problem from escalating and possibly damaging other elements on the system or causing power outages. If these critical communications are degraded due to interference, utilities may be unable to take preventative action that could then lead to a system failure, the letter said.
Meanwhile, the trade groups said that the Automated Frequency Coordination (AFC) system being proposed by the FCC to mitigate interference in the 6 GHz band remains untested and unproven.
As the FCC proceeds, the groups said that the agency should take steps in this proceeding to adequately protect critical infrastructure systems prior to expanding access to the 6 GHz band.
These steps include: (1) Requiring AFC for both indoor and outdoor unlicensed operations; (2) Securing the AFC system, particularly considering the potential threat of cyberattacks to mission-critical communications by CII; and (3) Testing the AFC system so it is proven to protect against interference to microwave systems, prior to allowing any unlicensed operations in the 6 GHz band.