When the U.S. Defense Department asked industry last year how it could develop 5G networks domestically, people grew concerned that the department was trying to compete with private companies or nationalize 5G.

A single question in the request for information made some lawmakers, defense businesses and interest groups worried that the Pentagon would stifle billions in commercial investment in a rush to build 5G to support advanced military technology that requires fast, reliable wireless connections — such as improved radar to help on the battlefield.

The Pentagon said that wasn’t the case, but newly released responses to the department’s 5G market research inquiry show the reaction from companies and interest groups ranging from Lockheed Martin and other primes to telecom giants to interest groups. Many tried to head off any hint of an interest in the idea of a nationalized 5G network, saying it’s a bad idea because the government wouldn’t use the full capacity of an exclusive network to make the sizeable investment worth it.

A federal-only 5G network is still not in the department’s plans, according to a recent statement to C4ISRNET.

“DoD does not plan to own or operate a national 5G network,” said Frederick D. Moorefield Jr., deputy CIO for command, control, communications and computers and for information infrastructure capabilities.

Many respondents argued the Pentagon can save money by pairing its ownership of midband spectrum, desired by commercial companies, with private-sector technologies and hardware. The DoD could still have priority access while making the most use of the spectrum, a finite resource, while allowing for commercial development of 5G networks.

But they also outlined security challenges that the Pentagon must address to keep the nation safe. For example, dynamic spectrum sharing could interfere with radars or reveal the location of military assets.

Other 5G-supported capabilities the Pentagon is exploring include smart warehouses to improve logistics speeds and augmented and virtual reality goggles for mission planning, training and operations. It’s also working on spectrum sharing with commercial partners at Hill Air Force Base, Utah, and Joint Base Lewis-McChord, Washington. Moorefield told C4ISRNET that the Pentagon had reviewed the responses and provided recommendations to the National Telecommunications and Information Administration, which regulates the electromagnetic spectrum.

“The RFI enabled us to ‘explore the art of the possible’ in terms of dynamic spectrum sharing, which, as noted, will inform NTIA efforts at the national level,” Moorefield wrote, adding the department doesn’t have a timeline for future actions on the RFI. “The DoD remains committed to ensuring mission effectiveness as well as close partnership with civil organizations, like NTIA and the FCC [Federal Communications Commission], to ensure the U.S. can be a leader with 5G technologies for both commercial as well as government/military uses.”

While many respondents wrote that they didn’t interpret the DoD’s question as trying to build a 5G network, several still warned the DoD that owning a 5G network would suppress U.S. development of 5G capabilities and be an inefficient use of department funds.

For example, Raytheon wrote that while total ownership would allow the department to ensure that the 5G systems “conform to all security and cyber requirements,” several other factors would make that ownership difficult to maintain.

“At the same time, total ownership creates the need for a highly-trained workforce and makes it difficult to provide a rapid technology upgrade path especially at the system level,” Raytheon responded. “In addition, each location may have unique requirements making a general DoD purchase more difficult.”

Instead, the department should work with industry, the respondents said.

“Such a network would provide DoD priority access to network bandwidth but also lever commercial volumes in semiconductors, equipment, devices and services to deliver to DoD a cost-effective service, as well as safeguarding adequate investment to keep it updated and globally competitive over the long run,” Google wrote.

Media reports from October suggested that one company, Rivada Networks, a company with ties to top Republican operatives, was lobbying for a contract. However, Rivada wrote in its reply to DoD that a nationalized network “would almost certainly be an inefficient use of spectrum, network and resulting broadband capacity.”

“The superior alternative is a network built to commercial scale and with private capital, while being shared with commercial users who are subject to preemption by DoD,” Rivada’s response read. “Because such a network would cover more ground and provide more capacity than a standalone, exclusive-use network, DoD would not lose anything from having to share: Total capacity and coverage would far exceed DoD’s needs.”

But dynamic spectrum sharing has its own national security concerns, which the Pentagon asked industry to identify. Companies listed interference with radars, operational security and cybersecurity as top concerns.

“If commercial 5G shares the same spectrum as DoD systems in the same vicinity and same time without mitigation, the former can interfere with DoD systems by desensing radar systems and reducing effectiveness,” wrote TrellisWare, a network technology company that has developed advanced waveforms for the Army.

Sharing spectrum with commercial providers could also allow adversaries to locate U.S. military assets, several companies warned. Operational security concerns include “generating accurate geolocation information as the positions and tracks of aircraft operating radars or other primary military users,” wrote Booz Allen Hamilton.

“Alternately, an adversary may be able to infer an aircraft’s location by monitoring the orchestration traffic managing the response of the 5G network as it adapts to protect the primary user,” the company wrote.

Iron Bow Technologies and other companies including Lockheed Martin warned of supply chain and cybersecurity risks involved with third-party vendors, a risk that’s taken on prominence recently after a major software supplier of the federal government was breached by Russian hackers and reportedly Chinese hackers.

“National security concerns are real but also manageable. So long as no national security information is passing to the commercial side, and as long as national security systems have access to the spectrum that they need, the fundamental concerns are satisfied,” Iron Bow wrote. “Where commercial databases are in use, attention must be paid to their security to prevent the databases from being misused, but this also is a known problem for which security solutions exist.”

Andrew Eversden covers all things defense technology for C4ISRNET. He previously reported on federal IT and cybersecurity for Federal Times and Fifth Domain, and worked as a congressional reporting fellow for the Texas Tribune. He was also a Washington intern for the Durango Herald. Andrew is a graduate of American University.

More In 5G