An access network is a type of network which physically connects an end system to the immediate router (also known as the “edge router”) on a path from the end system to any other distant end system. Examples of access networks are ISP, home networks, enterprise networks, ADSL, mobile network, FTTH. The term campus LAN refers to a LAN network that spans a single geographic location, such as a building or university campus. A campus LAN can be an entire network or part of an enterprise network. It mainly aims at providing consistent and secure network access while controlling data. A campus network describes the portion of an enterprise infrastructure that interconnects end devices to services such as intranet resources (residing in the data center) or the Internet. In spite of the high port count, the access switch usually provides the.