Global data center colocation and wholesale market revenue will top $48 billion by 2021, while Equinix and Digital Realty remain the leaders among nearly 1,200 global suppliers.

That’s according to 451 Research’s latest quarterly Datacenter KnowledgeBase (DCKB), which tracks nearly 4,500 data centers operated by almost 1,200 companies around the world.

In the third quarter of 2016, the data center colocation and wholesale market saw nearly $29 billion in annualized revenue, with most (42 percent) generated in North America and 31 percent in Asia-Pacific.

Following a year of significant M&A activity in 2015, the first three quarters of 2016 maintained the momentum with notable industry consolidation, including Equinix completing its acquisition of Telecity Group, TierPoint buying Windstream, and Digital Realty Trust taking on eight of Equinix’s European data centers.{ad}

The data center market continues to grow, not only in many of the main markets, but increasingly in areas outside of the global top 20, according to 451.

“Interest in edge markets is one of the factors driving consolidation,” said Leika Kawasaki, senior analyst of data-center initiatives at 451. “Over the next one to two years, we expect to see growing interest from top providers and investors in markets outside of the top 20, particularly in Asia and Latin America.”

In terms of annualized colocation and wholesale revenue, as of third-quarter 2016, Equinix and Digital Realty remained the global leaders, with 9.5 percent and 5.7 percent share, respectively. Once the Equinix acquisition of Verizon’s data-center business closes in mid-2017, Equinix’s market share is expected to expand to 11.4 percent of global annualized revenue, equivalent to double that of Digital Realty Trust, the second-largest provider.