VMware ranked No. 1 in terms of SDN revenue during the second half of 2018 narrowly outselling rival Cisco in the space, according to IHS Markit.

The firm puts VMware in first place with 22% of in-use SDN revenue and Cisco in second with 19%. Arista ranked No. 3 with 15%, white box vendors came in fourth with 10%, and Huawei rounded out the top five with 8%.

It also found SDN revenue increased by 34% in second half of 2018 compared to the first half and is expects the market to reach $20 billion by the end of 2023, up from $7 billion in 2018. This includes SDN in Ethernet switches, SDN controllers, SD-WAN appliances, and SD-WAN control and management software.

For VMware and Cisco, this includes their respective NSX and ACI product lines. Over the past couple years both vendors acquired top SD-WAN companies — Cisco acquired Viptela and VMware acquired VeloCloud — and made other moves to allow them to stretch their networking fabrics from the data center to the cloud and edge. VMware calls this “NSX everywhere” and Cisco calls it “ACI anywhere.”

The leading vendors are also focusing on intent-based networking to fuel SDN adoption, IHS Markit says. For example, Cisco more tightly integrated its intent-based networking with ACI in the second half of 2018. And at MCW in February, Huawei launched its intent-based network product.

“The next big innovation in switching is the inclusion of special-purpose artificial-intelligence (AI) silicon within the switch,” said Josh Bancroft, senior analyst at IHS Markit. “Huawei leads the pack with its announcement of the Ascend 910, which is included in the new Cloud Engine 16800. We can expect the bare-metal switch vendors to follow, and this is also expected to fuel SDN bare-metal switch adoption.”