Last week the Federal Communications Commission ruled that commercial wireless operators must allow subscribers from other carriers to roam onto their high-speed mobile data networks, but it has yet to rule on a key issue that might impact the scope of public-safety LTE networks.

The issue has to do with interoperable 700 MHz equipment. Approximately 18 months ago, Tier 2 and Tier 3 wireless operators filed a petition with the FCC to require that all 700 MHz equipment incorporate all four bands of the 700 MHz spectrum block.

Smaller operators allege that the two largest winners of the 700 MHz spectrum auction — Verizon Wireless and AT&T Mobility — are in effect blocking competitors by issuing requests for LTE equipment that only works in the band classes that they acquired at auction, and not the band classes held by smaller wireless players—or the D Block, which is expected to be reallocated to public safety, for that matter. Unlike past spectrum auctions, interoperability was not mandated for the 700 MHz auction.

Many smaller operators acquired 700 MHz spectrum licenses in the lower A, B and C Blocks, which lie in band class 12. Verizon’s licenses primarily are concentrated in the upper C Block, or band 13, while AT&T’s are in the upper A and B Block, or band 17. Smaller operators claim that Verizon and AT&T are leveraging their massive size to encourage network operators to build equipment that only supports the 700 MHz band classes they own, thus hurting the economies of scale for smaller operators.

Of course AT&T, Verizon and a handful of vendors are taking issue with the filing, saying that incorporating all bands not only would stifle technological innovation, but also would be technically challenging. These operators say market forces should dictate interoperability.

The public-safety community should be siding with smaller operators on this one. Yes, it’s true that Verizon’s LTE network will interoperate with public safety’s LTE networks given the operator’s alliance with Motorola — which will provide public-safety customers with an opportunity to leverage LTE applications across Verizon’s commercial network as a coordinated supplement to a private LTE network, or as a roaming partner when the private network is not available. But interoperability won’t be guaranteed on AT&T’s network or on smaller operators’ networks if the FCC doesn’t mandate interoperable 700 MHz equipment.

Public safety could use as many roaming partners as possible, and smaller operators would be critical roaming partners in rural areas — and they are moving just as fast toward LTE as their larger counterparts. Cellular South, for instance, is expected to roll out LTE services by the end of this year.

Having access only to Verizon’s network means public safety could pay higher roaming fees, too. Consequently, for all of these reasons, the public-safety sector would benefit from making deals with multiple operators for multiple, redundant backup opportunities across the U.S.

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