The generally accepted approach to these challenges is to provide a core network capability that has adequate switching capacity and throughput capability to support the combined traffic of the campus. To this core are attached edge switches to which are then connected the departmental LANs, application servers, storage appliances and other systems. So a wide range of edge environments are interconnected through a high-speed, high capacity core, which is, in turn, connected to the outside world. This concept is illustrated in highly schematic form here. In today's technology marketplace, there are competing approaches to many aspects of networking and systems deployment.
Ethernet is the most ubiquitous network access method in use today.
It accounts for the majority of LAN deployments and is used in many intranet environments as well. CAN deployments too. In an effort to make Ethernet meet the needs of campus environments, new variations of it have been under development and are finding their way into general use. These offer greater throughput capabilities than traditional Ethernet. But, Ethernet isn't the only network access method and while suitable for LANs, it has difficulty integrating with other network technologies in heterogeneous environments.