The Small Cell Forum announced “significant progress” in the development of two APIs to push interoperability between chips, equipment, and networks of different 5G vendors. The APIs “will transform the economics of deploying wireless networks and enable a competitive and innovative ecosystem” on a global scale, the organization explained.

One of the APIs will extend an original Small Cell Forum specification already being used in small cell chips and equipment to allow interoperability between 3G, 4G, or 5G physical layer and higher layer software. That work is led by Intel and Qualcomm.

The other API will focus on 5G networks to specify an interface between remote and centralized units of a 5G base station. It will apply to both indoor and outdoor 5G split radio access network (RAN)/small cell network (SCN) architectures, which will be important for dense yet cost-efficient deployments.

The work is designed to accelerate open networks “to meet pent-up demand for in-building coverage,” said David Orloff, chair of the Small Cell Forum. He noted that the group is focused on a single architecture to enable real world deployments to reduce the time it takes to bring products to market.

The APIs are designed to complement ongoing work by 3GPP and other industry groups working for common, open, multi-vendor networks. They are being finalized and published in mid-2019.

“The industry has an array of options to consider and it will take time for a stable ecosystem to develop,” added AT&T’s Prabhakar Chitrapu, chairman of the Small Cell Forum’s 5G working group. He explained that the work will “greatly increase” the readiness of open 5G products.

Roger Entner, an analyst at Recon Analytics, called the API work “an absolutely critical plumbing step” in the progression to 5G. “We’re on track with the pace of this work toward 5G.”

While Entner praised the efforts, he said a more worrisome problem is the more than 20 lawsuits filed in federal courts by cities and counties that object to small cell siting rules set last year by the Federal Communications Commission (FCC).

“The technical stuff at the [Small Cell Forum] will work itself through – that’s inevitable,” Entner said. “But we have to remember that 5G stands and falls by deployments of small cells. Cities are not approving small cell siting permits fast enough and are charging too much.”

Wireless industry trade group CTIA has estimated it will take 800,000 small cell installations nationwide to support 5G deployments using millimeter wave (mmWave) spectrum. Some cities have said the FCC ruling has improperly revoked their independent power to regulate where small cells are located, while others have objected to potential health effects from small cells.

Part of the problem, Entner suggested, is that average people and city officials don’t understand that small cells really are small, perhaps as small as a shoebox or a pizza box, and not as obtrusive as typical cell towers that have a far greater range than small cells.

“China deploys in a month as many smalls as the U.S. deploys in a year,” Entner said. “Nobody can say that’s a good thing.”