BGP-EVPN for VxLAN: The Future of Networking Unleashed

Explore the potential of BGP-EVPN in the realm of VxLAN overlay networks, dissecting its capabilities in addressing pressing challenges such as scalability, complexity, and security in modern networking environments.

Challenge in computer networks

The growth of any cast computer networks, driven by increasing data demands, diverse application requirements, and the rise of cloud computing, has pushed the networking status quo to rethink about the issues it faces such as complexity, scalability, and reliability. 


  • Network Congestion: As data traffic grows, network congestion becomes more prevalent. Ensuring smooth data flow and avoiding bottlenecks are ongoing challenges.
  • Network Management: With the rise of cloud computing, virtualization, and distributed systems, network management has become more complex. Administrators need sophisticated tools to monitor and manage networks effectively.
  • Quality of Service (QoS) and Traffic Prioritization: Guaranteeing the quality of service for critical applications like voice and video, and appropriately prioritizing traffic to meet service level agreements (SLAs) is a challenge in networks with diverse traffic types.
  • Network Interoperability: With the coexistence of various network technologies and devices, ensuring seamless interoperability between different components and vendors remains a challenge.


  • Network Scalability: The demand for higher bandwidth and the proliferation of connected devices, including IoT (Internet of Things) devices, place immense pressure on network scalability. Ensuring that networks can handle the increasing traffic and accommodate future growth is a constant challenge.
  • Data Privacy and Compliance: With the increasing amount of data transmitted over networks, ensuring data privacy and compliance with regulations such as GDPR (General Data Protection Regulation) and CCPA (California Consumer Privacy Act) is a critical challenge.


  • Security Threats: Cybersecurity is a significant concern as networks are vulnerable to various types of security threats such as malware, ransomware, DDoS (Distributed Denial of Service) attacks, and data breaches. Protecting networks and data from these threats requires constant vigilance and robust security measures.
  • Network Reliability and Downtime: Networks must be highly reliable, and any downtime can have severe consequences for businesses. Redundancy, failover mechanisms, and proactive monitoring are essential to minimize downtime.

Overall, the growth of computer networks and the evolution of modern networking requirements has led to the development and adoption of overlay network technologies, including routing protocol. These technologies have become crucial components in addressing the challenges and complexities of modern networking environments, providing scalable, agile, and efficient solutions for diverse networking scenarios.

Focus on Overlay networking technologies!

So far, it’s understood that computer networks are facing a huge challenge due to growth and globalization of businesses, and this has led to advent of overlay networking technologies. In this section, lets first focus on the advantages of virtual networks, which are a type of overlay network, and in the latter part focus on some of the challenges, including control-plane learning and VNI membership.

Key reasons to use VxLAN:

  • Network Virtualization: Overlay networks enable the creation of virtual overlays on top of the physical infrastructure, allowing the logical segmentation of networks for different tenants, applications, or services.
  • Scalability: Overlay technologies like VxLAN provide scalable solutions forexpanding network segments without major changes to the underlying physical network.
  • Segmentation and Isolation: Overlay networks allow for the isolation of traffic, improving security and network performance by creating separate broadcast domains or IP subnets.
  • Simplified Network Management: Overlay networks abstract the complexities of the underlay infrastructure, making network management and configuration more straightforward and adaptable.
  • Multi-tenancy: Overlay networks facilitate multi-tenancy scenarios by maintaining network isolation for different customers.
  • Centralized Control: Overlay networks often offer centralized management, allowing for easier policy enforcement, traffic engineering, and troubleshooting.
  • Protocol Flexibility: Overlay networks support various protocols and technologies, making them versatile and adaptable to different networking needs and scenarios.

Shortcomings of VxLAN

In summary, overlay networks, such as the VxLAN connections, provide flexible, scalable, and efficient solutions to meet the challenges of modern networking, making them invaluable for cloud computing, data centers, and other complex network environments. But at the same time implementing VxLAN without a control plane can lead to several shortcomings and challenges that affect the functionality, scalability, and manageability of the network.

Why overlay networks (VXLAN) need a better control plane?

Overlay networks require a strong control plane because they introduce an additional layer of complexity and abstraction on top of the underlying physical network. The control plane is responsible for managing and controlling the behavior of the overlay network, including addressing, routing, security, and the establishment of communication paths, such as ip routing. Bridging the gap between the overlay network and the physical network is crucial for ensuring seamless communication between nodes. The data plane, on the other hand, is responsible for forwarding data packets between nodes in the overlay network.

Visualize each tunnel as an overlay network, imagine manually configuring every tunnel with a custom value (end points, IP addresses, etc.).

Here's why a strong control plane is crucial for overlay networks (BGPEVPN for VxLAN):

  • Logical Abstraction: Overlay networks create a logical abstraction of the physical network, where endpoints may be geographically distributed or connected across various physical devices. A robust control plane is necessary to manage this abstraction and ensure proper communication between virtual entities in the overlay.
  • Address Management: Overlay networks often involve the use of encapsulation techniques like VxLAN or GRE to create tunnels between endpoints. The control plane assigns and manages these encapsulation headers, ensuring that data packets are correctly encapsulated and decapsulated as they traverse the overlay.
  • Routing and Path Selection: A strong control plane is needed to determine optimal paths for traffic within the overlay. This includes handling factors like load balancing, redundancy, and choosing paths that avoid network congestion or failures.
  • Network Security: Overlay networks require secure communication between endpoints, especially in scenarios like multi-tenancy or connecting different cloud environments. The control plane is responsible for enforcing security policies, authenticating endpoints, and ensuring encrypted communication.
  • Dynamic Configuration: Overlay networks often need to adapt to changes in the underlying physical network or in the overlay itself. A robust control plane enables dynamic reconfiguration of overlay resources, such as tunnels and routes, based on changes in network topology or requirements.
  • Traffic Engineering: To manage traffic flow and ensure quality of service, a strong control plane can implement traffic engineering techniques, such as traffic prioritization and bandwidth reservation.
  • Scaling and Virtualization: As overlay networks grow in scale and complexity, the control plane must be able to scale accordingly. It should support many endpoints, handle increased traffic, and effectively manage the provisioning and deprovisioning of overlay resources.
  • Centralized Management: An effective control plane provides centralized management and visibility into the overlay network, which simplifies monitoring, troubleshooting, and policy enforcement.
  • Interoperability: In multi-vendor environments or when integrating with existing networks, a robust control plane ensures that overlay network components can communicate and interoperate seamlessly.
  • Failover and Redundancy: The control plane plays a critical role in failover scenarios, automatically rerouting traffic when overlay network paths or endpoints experience failures.

In summary, overlay networks introduce an additional layer of abstraction and
complexity. A strong control plane is essential for managing this complexity, ensuring
proper communication, security, scalability, and adaptability within the overlay network.
Additionally, the VxLAN header, which provides encapsulation and decapsulation of
packets for efficient communication between virtual machines, is a crucial component of
the VxLAN overlay network.

How BGP - EVPN technology solves this problem and why it has been widely adopted

BGP EVPN (Ethernet Virtual Private Network) is an extension of the BGP (Border Gateway Protocol) that is used to provide efficient and scalable Ethernet-based VPN solutions, including mp-bgp evpn. It is commonly used in data centers and service provider networks to address various use cases. Here are some of the main capabilities of BGP-EVPN protocol:

  • Auto-discovery of the remote VTEPs and their L2-VPN membership information.
  • Manual configuration of remote VTEP information is not required.
  • Distribution of locally learned MAC addresses to remote VTEPs instead of relying on data-plane driven MAC learning. This helps in scenarios where flooding unknown unicast traffic is not desirable.
  • Distribution of locally learned MAC- IP address bindings (from ARP table) to remote VTEPs
  • Helps in implementing many advanced features like multi-homing, traffic load balancing, ARP suppression, by distributing additional information independently and as meta-data in MAC/IP advertisement.


In conclusion, the adoption of BGP EVPN with virtual extensible lan and leaf switches represents a significant advancement in modern networking architecture, offering a robust solution to address the complex challenges faced by today's data centers and networks. With its innovative features such as network virtualization and efficient multitenancy support, BGP EVPN presents a compelling approach to enhancing scalability, security, and flexibility.

As organizations strive to meet the ever-increasing demands of a dynamic digital landscape, BGP EVPN deployment emerges as a pivotal tool to facilitate the evolution of network infrastructures. Its ability to efficiently manage large-scale networks, optimize resource utilization, and ensure consistent and secure communication between distributed endpoints underscores its relevance in the face of evolving technology requirements.

By integrating BGP EVPN address family, including the route distinguisher, into our network architecture, we position ourselves to not only overcome the current networking challenges but also to embrace future innovations with confidence. The advantages offered by BGP EVPN address family - streamlined network operations, improved resource allocation, and the seamless integration of cloud and on-premises environments - make it a cornerstone for building robust and resilient networks in the digital era. With BGP EVPN routes as an essential component, we are poised to usher in a new era of network efficiency, agility, and adaptability, driving us closer to achieving our network goals in the rapidly changing landscape of modern connectivity.