News

Cisco Hedges SDN Bets with Overlay Support

• By David Ramel
• 02/09/2015

The complicated relationship of Cisco Systems Inc. with the upstart software-defined networking (SDN) movement took another twist with new support for open standards overlay technology.

Many industry observers believe Cisco, the traditional networking powerhouse, has the most to lose as conventional approaches are disrupted by the new SDN techniques, such as putting network intelligence into a software control layer rather than in proprietary switches and other hardware.

The company has been involved in SDN-related open standards efforts but has also positioned its own Application-Centric Infrastructure (ACI) approach as being "better" than SDN.

It continues to hedge its bets, however, last week announcing it's "furthering its open standards approach to SDN" and "complementing" its ACI approach by supporting the IETF standard Border Gateway Protocol – Ethernet Virtual Private Network (BGP EVPN) protocol for overlay networks.

The new capability will come to the company's Nexus 9000 Series switches this month and will be rolled out to Nexus 7000 switches and ASR 9000 routers in the second quarter of the year.

Cisco said the new support gives more options to customers, who can now choose to run the Nexus 9000 switches in standalone mode on traditional topology networks, with VXLAN overlays or in ACI mode with Cisco software.

"Overlay networks provide the foundation for scalable multi-tenant cloud networks," Cisco said in a statement. "VXLAN, developed by Cisco along with other virtualization platform vendors, has emerged as the most-widely adopted multi-vendor overlay technology. In order to advance this technology further, a scalable and standards-based control plane mechanism such as BGP EVPN is required.

"Using BGP EVPN as a control-plane protocol for VXLAN optimizes forwarding and eliminates the need for inefficient flood-and-learn approaches while improving scale," the company continued. "It also facilitates large-scale deployments of overlay networks by removing complexity, fosters higher interoperability through open standard control plane solutions, and access to a wider range of cloud management platforms."