When designing a WLAN, determining the number and location of access points is essential to ensure adequate coverage, capacity, and performance, while minimizing interference and ensuring seamless connectivity.

EVPN-VXLAN is an overlay solution that extends Layer 2 network segments across a Layer 3 WAN. It enables seamless connectivity between remote sites or data centers while maintaining Layer 2 adjacency, making it ideal for distributed environments.

Using a Virtual Chassis (VC) introduces a single point of failure in the management plane, as all member switches depend on a master for control. Replacing the VC with ESI-LAG (Ethernet Segment Identifier - Link Aggregation Group) allows dual-homed servers to connect to independent leaf switches while maintaining resiliency and independent management planes—thus eliminating the single point of failure.

Reducing the oversubscription ratio means provisioning more uplink bandwidth relative to access bandwidth, which improves congestion handling and performance but also increases network cost due to the need for additional or higher-capacity links and equipment.

VXLAN is a network virtualization technology that provides a Layer 2 overlay over a Layer 3 underlay. It enables the extension of Layer 2 segments across a Layer 3 infrastructure, facilitating scalable multi-tenant data center networks.

The diagram shows an enterprise WAN connected to two different ISPs through edge routers, with security elements in place. This configuration is characteristic of an Internet edge design, where the enterprise network interfaces with external service providers, providing redundancy and secure access to the internet.

In a 3-stage IP fabric, each leaf node must connect to every spine node to ensure full mesh connectivity at Layer 3 between leafs via the spine layer. This design supports ECMP and optimal traffic distribution across the fabric.

The oversubscription ratio in an IP fabric is influenced by the number of spine nodes relative to the number of leaf nodes and their uplinks.

Removing spine nodes reduces available uplink bandwidth, increasing oversubscription.

Adding spine nodes increases available bandwidth between leafs and spines, decreasing the oversubscription ratio.

For a 120-meter (400-foot) connection between switches, multimode fiber is the most reliable and cost-effective option. It supports higher bandwidth and longer distances than UTP (which is limited to 100 meters) and is more stable and secure than a wireless solution.

PTX Series routers are purpose-built for the core network, offering ultra-high throughput, scalability, and low-latency forwarding ideal for service provider and large-scale data center cores.