Overview

Enterprise networks are undergoing massive transitions to accommodate the growing demand for cloud-ready, scalable, and efficient networks. There’s also demand for the plethora of Internet of Things (IoT) and mobile devices. As the number of devices grows, so does network complexity with an ever-greater need for scalability, segmentation, and security. To meet these challenges, you need a network with Automation and Artificial Intelligence (AI) for operational simplification. IP Clos networks provide increased scalability and segmentation using a well-understood standards-based approach (EVPN-VXLAN with GBP).

Most traditional campus architectures use single-vendor, chassis-based technologies that work well in small, static campuses with few endpoints. However, they are too rigid to support the scalability and changing needs of modern large enterprises. Multi-Chassis Link Aggregation Group (MC-LAG) is a good example of a single-vendor technology that addresses the collapsed core deployment model. In this model, two chassis-based platforms are typically in the core of a customer’s network and deployed to handle all Layer 2 (L2) and Layer 3 (L3) requirements while providing an active-backup resiliency environment. MC-LAG does not interoperate between vendors and is limited to two devices. The lack of vendor interoperability creates vendor lock-in.

A Juniper Networks EVPN-VXLAN fabric is a highly scalable architecture that is simple, programmable, and built on a standards-based architecture ( https://www.rfc-editor.org/rfc/rfc8365 ) that is common across campuses and data centers.

The Juniper campus architecture uses an L3 IP-based underlay network and an EVPN-VXLAN overlay network. Broadcast, unknown unicast, and multicast (BUM) traffic is handled natively by EVPN and eliminates the need for Spanning Tree (STP) or Rapid Spanning Tree Protocols (RSTP). A flexible overlay network based on VXLAN tunnels combined with an EVPN control plane efficiently provides L3 or L2 connectivity. This architecture decouples the virtual topology from the physical topology, which improves network flexibility and simplifies network management. Endpoints that require L2 adjacency, such as IoT devices, can be placed anywhere in the network and remain connected to the same logical L2 network.

With an EVPN-VXLAN campus architecture, you can easily add core, distribution, and access layer devices as your business grows without a need for redesigning your network. As EVPN-VXLAN is vendor-agnostic, you can use the existing access layer infrastructure and gradually migrate to access layer switches. This supports EVPN-VXLAN capabilities once the core and distribution part of the network is deployed. Connectivity with legacy switches that do not support EVPN VXLAN is accomplished with standards-based ESI-LAG. ESI-LAG uses standards-based Link Aggregation Control Protocol (LACP) to interconnect with legacy switches.