By some estimates, over 90% of all 911 calls in some areas are made from wireless phones. But the kinds of disasters that can generate those calls can also impact the infrastructure that supports them – meaning, hurricanes, wildfires and other natural or man-made calamities can hobble or destroy the wireless networks we rely on to get help.
So what is the wireless industry – including specifically AT&T, Verizon and T-Mobile – doing today to make sure their networks remain operational during such crises?
That's the exact question that regulators at the FCC asked. In their responses last week, industry players provided plenty of vague assurances as well as some facts, figures and anecdotes. Here's a sampling of what they said:
- Maintains up to 8 hours of backup battery power at all macro sites, and "where possible" designs those sites to support backup power through diesel generators that last between 24-72 hours on a single tank of fuel.
- Holds disaster recovery reviews with all its backhaul providers before every storm season. The company also uses a more resilient fiber ring configuration where possible.
- Recently "significantly increased" its investments in portable cell sites and other such equipment for emergency network operations.
- Committed in 2019 to publish a list of sites out of service on its website, and did so throughout the 2020 hurricane season.
- Said that "in most areas, Verizon customers benefit from overlapping cell site coverage," though it didn't provide details.
- Has tools "that allow the network to self optimize under certain conditions to maintain coverage and capacity as best as possible when certain sites become inoperable."
- Said that all of its network switches, Network Operations Centers (NOCs), data centers, and other key sites "have permanent, on-site backup generators that will keep the network running."
- Has added "thousands" of generators – both fixed and portable – to keep the power on at select cell sites, though the company didn't provide details.
- Has implemented a "distributed architecture for interconnection redundancy" using dual fiber connections at switch locations.
- Participates in training and preparation work with agencies including the Department of Homeland Security. "In a few weeks, T-Mobile will participate in a DHS Hurricane Preparedness seminar," the operator boasted.
- Works with weather forecasters to "inform preparations and decide if and where equipment and response teams are needed. Based on this information, T-Mobile proactively sends people, supplies, and equipment to locations close to the projected areas of impact."
- Recently doubled the size of its emergency management fleet of satellite-equipped portable cell sites.
- Touted its Network Disaster Recovery (NDR) program, launched in 1992. The company said it has invested more than $650 million into its NDR program.
- Also touted its Disaster First Strike Team (DFST) that the company said "conducts training exercises and readiness drills to help ensure our networks and personnel are prepared to respond ahead of disasters. DFST is formed by hundreds of volunteers across the company trained to assist disaster-stricken areas in all aspects of restoration response, ranging from handling large-scale emergency generator deployments to rebuilding damaged network infrastructure."
- Said that "all of AT&T's macro sites have a backup power solution, consisting of either a battery or a combination of battery and generator. These solutions are engineered to last between 4-72 hours depending on the type of facility and what is feasible at each location." The company added that it has committed to deploying over 1,000 new fixed generators and power resources at cell sites in California specifically, due to wildfires there.
Wireless Resiliency Cooperative Framework
The nation's top wireless network operators in 2016 created a disaster recovery plan with trade group CTIA. The plan includes voluntary coordination among carriers, local governments and others, as well as promises to share information during and after emergencies and disasters. For operators specifically, the framework supports "reasonable" roaming among wireless providers under disaster arrangements when technically feasible, as well as promises of "mutual aid."
And that work was enhanced in 2020 with a general agreement between the wireless industry and the utility industry to coordinate their disaster responses to keep cell sites up and running.
It's all working, according to the CTIA trade group.
"The United States experienced a record number of billion-dollar weather and climate disasters in 2020. Yet, wireless services largely remained available throughout most impacted areas, in large part due to recent investments by wireless providers," the association wrote to the FCC.
But some critics say that more should be done.
A debate over federal mandates
"The Wireless Resiliency Cooperative Framework's voluntary approach does not provide the necessary federal safeguards to ensure that people have access to communications during and after a disaster," argued public interest group Free Press in a filing on the issue. "The commission must create instead a proactive and comprehensive approach to disaster response, to adequately address future threats. A new disaster response playbook should fulfill the need for the commission to take a lead role in establishing a mandatory floor for network resiliency."
That position may have some traction with FCC Acting Chairwoman Jessica Rosenworcel.
"It's time for the FCC to develop a consistent and reliable approach to ensuring the resiliency of networks in disaster," she said in 2019, prior to her appointment as acting chairwoman. "We don't need more comments, we need enforceable commitments."
She also pointed to a Government Accountability Office (GAO) report from 2018 on the wireless industry's network-resiliency framework that found a number of shortcomings, including a failure by the FCC itself to "actively communicate information" about the efforts.
Not surprisingly, the wireless industry is firmly against government mandates about how operators should run their networks.
"The absence of rigid government mandates has permitted wireless carriers to take flexible, effective approaches to network design," T-Mobile argued. "For example, investments in networks subject to hurricanes often will differ from investments in networks more prone to earthquakes. There simply is no 'one-size-fits all' solution to resiliency."
"Overly prescriptive regulations risk undermining the flexibility to deploy new services and impeding the ability of providers to utilize a variety of tools for maintaining services," CTIA said.
Further, some companies insisted that government requirements could have unforeseen consequences. "Requiring backup power at all sites would make many technically infeasible due to space and engineering constraints, and in extreme cases could legally preclude the deployment of new facilities due to siting or environmental restrictions," Verizon wrote. "And such a policy would adversely affect the deployment and availability of new 5G services that rely heavily on smaller facilities inconspicuously installed in more dense urban and suburban areas."
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