VPN (Ethernet Virtual Private Network) is a WAN technology used to extend Layer 2 and Layer 3 connectivity between different network sites and segments. It is commonly used for interconnecting Layer 2 networks within and between large data centers. EVPN reduces complexity by integrating different control planes. This integration separates the forwarding plane from the control plane, enhancing traffic balance and flexibility in deployment and operation.
Additionally, with its ability to carry L3VPN services, EVPN reduces protocol complexity. The fundamental network technologies associated with EVPN are Ethernet over MPLS and Ethernet over VXLAN - both of which enable efficient and reliable use of Ethernet for virtual private networks in a WAN context.
One of the key advantages of EVPN is its ability to streamline connectivity by subverting the traditional mechanism of learning MAC addresses solely on the forwarding plane. Instead, it introduces a control plane and utilizes BGP extensions to transmit MAC address information. This approach, based on MP-BGP, defines a series of new BGP EVPN route types that enable different sites to learn MAC addresses from one another.
The main EVPN services include:
Ethernet over MPLS (Multiprotocol Label Switching), Ethernet over VXLAN (Virtual Extensible LAN) or Ethernet over IP, supporting different Ethernet services such as E-Line EVPL/EPL and ELAN.
EVPN can also be integrated with PBB (Provider Backbone Bridging) for data center interconnect applications and Ethernet E-LAN services. In addition, multicast VPN (MVPN) allows organizations to distribute multicast traffic between different sites.
Ethernet Virtual Private Network (EVPN) and Virtual Private LAN Service (VPLS) technologies are both widely used to extend Layer 2 connectivity. However, the main difference lies in how this is achieved. The advantages of EVPN over VPLS include:
Although EVPN was introduced more than a decade ago, it is still regarded as a "next-generation technology”, especially when deployed with segment routing (SR-MPLS / SRv6, to enhance path control and traffic engineering). Adoption is increasing with the expansion of data centers and growth in demand from global companies needing international WAN connections.
Multinational corporations, particularly those operating across different continents, often encounter challenges in efficiently linking and managing diverse data centers and operational resources. EVPN implementation offers a flexible and scalable alternative, by facilitating seamless communication between data centers on overlay networks. Additionally, it enables workload mobility and resource optimization.
EVPN is also a compelling option in a multi-tenancy scenario, where service providers need to secure private connections for each customer to meet individual connectivity requirements. Here, EVPN segmentation allows tenants to operate independently from each other.
The benefits of EVPN include:
Simplified network architecture: Integration of Layer 2 and Layer 3, and different control planes, simplifies network connectivity mechanisms and reduces complexity. Separating the forwarding and control planes helps balance traffic and increases flexibility in deployment and operation.
Scalability: EVPN is highly scalable, making it suitable for large-scale data center deployments or large, geographically diverse enterprise networks.
Flexibility: EVPN supports multiple network topologies (including any-to-any, hub-and-spoke, full mesh, and partial mesh configurations), enabling organizations to tailor their network architecture for specific requirements and unique needs.
Decreased complexity: By carrying both Layer 2 and Layer 3 Virtual Private Network (VPN) services, EVPN reduces protocol complexity, simplifying network management and operation.
Improved security: EVPN offers enhanced security features, including MAC address mobility and selective multicast replication - enhancing data security and integrity across the network.
In short, EVPN empowers service providers to equip modern organizations with powerful and efficient network connectivity - offering secure, scalable, and highly flexible solutions to support a wide spectrum of VPN services.
Layer 2 Ethernet services using Ethernet Virtual Private Network (EVPN) as the overlay control plane are a cornerstone of our Ethernet strategy - enabling us to directly support the specific needs of our customers.
Primarily, we use EVPN when configuring Ethernet point-to-point EVPL and any-to-any ELAN services. We chose EVPN specifically because it allows more efficient use of network resources, easy configuration, and additional service features which create a steppingstone towards further network innovation. Our EVPN-/ BGP-based configuration employs Segment Routing (SR) Low Latency Plane by using the opaque coloring in BGP.
Segment routing is a protocol which runs on top of our Intermediate System-to-Intermediate System (IS-IS) routing protocol. With segment routing, different 'flex-algos' (routing planes) can be established. All links in Arelion’s network have a latency metric which we use to create a low-latency flex-algo, enabling us to route traffic based on the lowest possible latency. This dynamic, low-latency approach to segment routing provides extremely fast rerouting times, benefiting enterprise customers who rely on diverse ethernet services running across our #1 ranked global Internet backbone.
We have many customer cases from the finance sector, where security is a necessity, and low latency a requirement. Here is a real-life example where Arelion implemented a high-bandwidth EVPN-based ELAN solution:
It is important to emphasize that each connection provided by Arelion operates on a segment routing-based low-latency plane, ensuring selection of the shortest latency path between any two locations. Traffic prioritization guarantees the best possible user experience and performance data is accessible via our portal, which is safely located within our own network. Multiple paths are available between any two locations in our network, at strategically located Points of Presence (PoPs) close to our customers.
Additionally, our comprehensive service level agreements (SLAs) simplify the decision-making process when selecting a service provider. On top of that, we have established a high level of trust with our long-term hardware vendors and network partners and this enhances the reliability of our network, by serving as additional insurance for customers looking to seamlessly interconnect global business-critical sites.
For more details about Arelion’s solutions, contact our sales and solution experts.
