Campus wired network design

LAN is a network infrastructure that provides access to network communication services and resources for end-users and devices distributed on individual floors or buildings. You can create a campus network by interconnecting a set of LANs distributed in smaller geographical areas. The concept of campus network design covers small networks using a single LAN switch, up to ultra large networks with thousands of connections.

The wired LAN in the park can realize the communication between the devices in the buildings or building groups, as well as the interconnection with the WAN of the network core and the Internet edge.

Layered design model

The campus wired LAN adopts a layered design model, which decomposes the design into modular groups or layers. Hierarchical design allows each layer to implement specific functions, thereby simplifying network design and simplifying network deployment and management.

Modularity in network design allows you to create design elements that can be replicated throughout the entire network. Copying provides a simple way to expand networks and a consistent deployment method.

In flat or mesh network architectures, changes often affect a large number of systems. Layered design helps to limit operational changes to network subsets, making it easy to manage and improving resilience. Modularize the network into small, easy to understand elements, and improve resilience through improved fault isolation.

Each layer (access layer, distribution layer, and core layer) provides different functions and capabilities for the network. Depending on the characteristics of the deployment site, you may need one, two, or all three layers.

For example, a site occupying a single building may only require access and distribution layers, while a park with multiple buildings may require all three layers.

No matter how many layers are implemented in one location, the modularity of this design ensures that each layer provides the same services, and in this architecture, the same design methods will be used.

Access layer platform

The preferred options for wired LAN in the park include the following Cisco switches as access layer platforms

Distribution layer

The distribution layer supports many important services. In networks that require end-to-end LAN traversal, whether between different access layer devices or from access layer devices to the WAN, the distribution layer will facilitate this connection.

The distribution layer provides connectivity to network-based services, WANs, and Internet edges. Network based services may include but are not limited to Wide Area Application Services (WAAS) and WLAN controllers. Depending on the size of the LAN, these services and the interconnection with the WAN and the Internet edge may reside on the distribution layer switch, which also aggregates LAN access layer connections. This is also known as a folding core design, as the distribution serves as the third aggregation layer for all devices.

Two layer design: The distribution layer serves as the folding core

Larger LAN designs require dedicated distribution layers to provide network-based services, rather than sharing connections with access layer devices. With the increasing density of WAN routers, WAAS controllers, Internet edge devices and WLAN controllers, the ability to connect to a single distribution layer switch becomes difficult to manage. There are many factors driving the adoption of LAN designs with multiple distributed layer modules:



The number of ports and port bandwidth that a distributed layer platform can provide affect network performance and throughput. When all LAN and network-based services rely on a single platform, network resilience is a factor, and regardless of the design of the platform, it may experience a single point of failure or unacceptable large fault domains.

Distributed layer platform

The preferred Cisco switches for deploying the wired LAN distribution layer in the park include:



The core layer of LAN is a crucial part of scalable networks, but its design is one of the simplest parts. The distribution layer provides fault domains and control domains, with the core representing a 24x7x365 uninterrupted connection between them. This is essential for organizations in modern business environments, where connection to resources is crucial for conducting business. The connection to and from the core is limited to the third layer, which can improve elasticity and stability.

Core layer platform

The preferred Cisco switch for use as the core layer platform in the park is:


Capacity, density, and functionality are the main differences driving platform selection. Both leading platforms have sibling platforms, which may be suitable for core roles in existing networks or networks that do not require the full functionality of leading platforms.