Wired and Wireless Convergence

What Is Wired and Wireless Convergence?

Initially, Wi-Fi networks served as an extension and supplement to wired networks. However, with the rapid expansion of wireless networks, many organizations are now deploying fully-wireless campus networks at scale. This transition marks a shift in wireless networks from a "supporting role" to a "leading role". In traditional setups, whether using standalone wireless access controllers (WACs) or WAC card solutions, wireless and wired traffic remain completely separate. This separation necessitates distinct management for network traffic, fault locating, access authentication, and policy implementation, which complicates maintenance and management. To address these issues, industry vendors have started to introduce wired and wireless convergence solutions that unify the forwarding and management of both network types.

Why Do We Need Wired and Wireless Convergence?

In traditional campus network deployments that combine wired and wireless networks, three primary architectures are commonly used: Fat AP architecture, off-path standalone WAC + Fit AP architecture, and ACU2 card + Fit AP architecture.

Wired Network + Wireless Network (Fat AP)

Fat APs (Access Points) connect directly to access switches and emit radio signals for wireless terminals to access the network. They handle not only radio signal emission but also management and control functions like security encryption, user authentication, and user management independently. However, each Fat AP operates autonomously without centralized management, making them difficult to manage collectively.

Wired Network + Wireless Network (Off-Path Standalone WAC + Fit AP)

To facilitate centralized management, the "WAC + Fit AP" architecture was introduced. This setup involves WACs and Fit APs, where Fit APs handle only radio signal emission and management functions are offloaded to a standalone WAC. The WAC uses the Control And Provisioning of Wireless Access Points (CAPWAP) protocol to manage all Fit APs centrally. Typically, the WAC connects to a core or aggregation switch off-path. This architecture simplifies management but keeps wired and wireless traffic separate.

Wired Network + Wireless Network (ACU2 Card + Fit AP)

Wired and wireless networks have gradually been integrated using WAC cards. Despite this integration, wired and wireless data traffic are still processed separately: wired traffic by the switch and wireless traffic by the WAC card on the switch. True convergence means integrating the switch processing wired services and the WAC processing wireless services into a single device for unified management. An example is the value-added service card installed on a switch to process wireless services, overlaying a wireless network on the wired infrastructure to provide wireless access capabilities, thereby simplifying device management.

Network Architecture of Wired and Wireless Convergence

In a converged network topology, both wired and wireless service traffic are centrally managed by switches. Wired and wireless services are uniformly configured and managed on these switches, achieving true convergence. This unified approach significantly simplifies management and reduces network deployment costs.

How Does Wired and Wireless Convergence Work?

A switch integrated with the WAC function, known as a native WAC, provides centralized management, authentication, and policy control for both wired and wireless services. The native WAC can identify wireless packets, encapsulate them with a CAPWAP header, and decapsulate CAPWAP packets, processing all packets similarly. This eliminates the need to forward wireless traffic to a separate WAC and back to the switch, thereby removing bottlenecks in the wireless network.

The native WAC enhances wireless traffic forwarding capabilities to Tbit/s-level, reducing the need for standalone WACs or WAC cards and thereby lowering costs and potential failure points. In campus networks, a single switch can provide WAC functions and converge the forwarding, control, and management planes. This network element-level convergence resolves the issue of separate traffic control and forwarding for wired and wireless networks. Additionally, the high switching capability and scalability of the switch eliminate bottlenecks in centralized traffic forwarding seen in standalone WACs or WAC cards.