This chapter discussed campus network design fundamentals using a multilayer design and the positioning of switches in campus modules.
Geography, application requirements, data link layer technology, cabling, and type of traffic forwarding are the factors you must consider when designing a campus network.
Location of nodes and the distance between them determine a campus network's geography. Intra-building, inter-building, and distance remote building are geographical structures that serve as guides to determine Enterprise campus requirements.
Characterization of applications that are used on a network can determine enterprise traffic patterns. Four types of application communication are client-client, client-distributed server, client-Server Farm, and client-Enterprise Edge.
Switched technology has many benefits over shared technology, including higher bandwidth support, larger network diameter, additional Layer 2 and Layer 3 services, and high availability.
Deciding whether to use Layer 2 or Layer 3 switching involves the consideration of network service capabilities, the size of the network segments, and maximum network failure convergence time that can be tolerated.
The most common physical transmission media used in modern networks are twisted-pair cables (copper) and optical cables (fiber). The choice of physical media depends on bandwidth and the distance between devices.
Network traffic affects the campus design. Considerations include application traffic patterns, the presence of multicast traffic, and the presence of delay-sensitive traffic. Multicast design considerations can prevent flooding of the traffic to all switched ports.
The Building Access module aggregates the workstations or hosts on a Layer 2 device. The distribution layer aggregates the access layer and uses a combination of Layer 2 and Layer 3 switching to segment workgroups and isolate segments from failures and broadcast storms.
The Campus Backbone and Server Farm modules require fast and resilient connectivity. Campus backbone switches are Layer 2 and Layer 3 switches that are primarily focused on wire-speed forwarding on all interfaces.
In the Edge Distribution model, the speed of switching is not as important.