Explain the concept of Cisco EVN (Easy Virtual Network).

Cisco's Easy Virtual Network (EVN) is a technology designed to simplify the deployment and management of virtual networks within a networking environment. It is particularly beneficial for service providers and enterprises that need to host multiple virtual networks on shared infrastructure.

  1. Virtual Network (VNET):
    • EVN allows the creation of multiple virtual networks, known as Virtual Network Identifiers (VNETs), on a single physical infrastructure.
    • Each VNET operates as an independent entity, providing segmentation and isolation for different tenants, departments, or business units.
  2. Separation of Routing and Forwarding Tables:
    • In traditional networking, routing and forwarding tables are closely tied together. EVN decouples these functions, providing more flexibility in network design.
    • Each VNET has its own routing table, allowing for independent control of the routing domain for each virtual network.
  3. Simplified Configuration:
    • One of the primary goals of EVN is to simplify network configuration. It abstracts the complexities associated with managing multiple virtual networks, making it easier for network administrators.
    • This simplification aims to reduce the likelihood of configuration errors and enhance overall operational efficiency.
  4. Inter-VNET Communication:
    • EVN provides mechanisms for controlled communication between different virtual networks.
    • Administrators can manage and configure inter-VNET communication, enabling selective sharing of resources and data between virtual networks based on business requirements.
  5. Integration with MPLS (Multiprotocol Label Switching):
    • EVN can be integrated with MPLS, a protocol used for efficient packet forwarding.
    • MPLS enhances scalability and performance by allowing the creation of label-switched paths, providing a more efficient way to forward packets within the network.
  6. VRF-Lite (Virtual Routing and Forwarding):
    • EVN employs the concept of VRF-Lite to achieve network segmentation.
    • Each VNET is associated with a specific Virtual Routing and Forwarding (VRF) instance, creating isolated routing instances for different virtual networks.