SD-WAN EVPN

What Is SD-WAN EVPN?

SD-WAN EVPN is a VPN technology that leverages BGP to relay encapsulation details among various locations through the control plane rather than the data plane. It introduces novel BGP SD-WAN pathways relying on BGP infrastructure and employs EVPN IP prefix routing for the dissemination of service-oriented pathways.

What Is the Relationship Between SD-WAN and EVPN?

SD-WAN Brief

SD-WAN presents an affordable, straightforward, and maintenance-friendly WAN solution tailored for the smaller-scale business sector. In the past, WANs relied on private lines and VPNs for connectivity. A private line is a dedicated network link exclusive to an organization, known for its high cost and limited flexibility. Meanwhile, setting up a VPN over a public network comes with significant maintenance expenses. Consequently, the emphasis is on maximizing existing resources to eliminate the need for new hardware purchases, streamline manual deployment processes, and reduce overall operating costs. SD-WAN addresses these challenges by incorporating controllers and versatile hardware devices. These components enable controllers to manage hardware directly over the public network, utilize software capabilities to identify services proactively, and ensure the delivery of optimal service quality. To explore further details, refer to SD-WAN.

EVPN Brief

A WAN primarily serves as a means for facilitating communication between different geographical regions. However, for enterprises, establishing Layer 2 network connectivity across regions can pose significant challenges. While L2VPN technology has been utilized in the past, its reliance on ARP broadcast for remote MAC address learning leads to high bandwidth utilization and subpar performance. Given the evolving technological landscape and diverse use-case scenarios, L2VPN falls short in meeting the demands for secure private line connections. In response to this, the industry introduced Ethernet Virtual Private Network (EVPN) as an alternative solution.

EVPN represents a VPN framework that leverages BGP extension to exchange MAC addresses at the control plane level, addressing the shortcomings associated with traditional VPNs' MAC address learning methods. For more detailed information, refer to EVPN. In the realm of Software-Defined WAN (SD-WAN), EVPN is deployed to establish Layer 2 network interconnections across different regions using public networks.

Why Is SD-WAN EVPN Required?

It addresses the issues related to excessive consumption of network resources, complex deployment processes, and subpar network performance commonly associated with traditional VPNs.

• By segregating the service network from the transport network, it ensures swift and secure data transmission.

• The implementation of full-mesh tunnels between various sites facilitates efficient data exchange within the service network, streamlines configuration tasks, reduces network link count, and enhances overall network efficiency.

• Facilitates rapid and secure transmission of service data, thereby guaranteeing smooth operation of services.

It removes constraints imposed by standard DSVPN specifications and network configurations.

• Through the integration of BGP, tunnel construction is no longer reliant on VPNs. The number of tunnels connecting two sites corresponds directly to the number of links between them, eliminating the need for the NHRP protocol. BGP peer connections are established independent of physical links, with common sites only requiring BGP peer connections with route reflectors (RRs). Furthermore, key distribution occurs uniformly without necessitating IKE negotiations.

• Decoupling control and data nodes enables the use of routing policies for network topology governance. Multiple topology modes, including hub-spoke, full-mesh, and hybrid configurations, can be deployed to adapt to diverse and intricate scenarios.