LAN

LAN

The term Local Area Network (LAN) refers to a local network, or a group of interconnected local networks that are under the same administrative control. In the early days of networking, LANs were defined as small networks that existed in a single physical location. While LANs can be a single local network installed in a home or small office, the definition of LAN has evolved to include interconnected local networks consisting of many hundreds of hosts, installed in multiple buildings and locations.

 The important thing to remember is that all of the local networks within a LAN are under one administrative control. Other common characteristics of LANs are that they typically use Ethernet or wireless protocols, and they support high data rates.

 The term Intranet is often used to refer to a private LAN that belongs to an organization, and is designed to be accessible only by the organization's members, employees, or others with authorization.

Adding Hosts to Local and Remote Networks

Within a LAN, it is possible to place all hosts on a single local network or divide them up between multiple networks connected by a Distribution Layer. The answer depends on desired results. Placing all hosts on a single local network allows them to be seen by all other hosts. This is because there is one broadcast domain and hosts use ARP to find each other.

 In a simple network design it may be beneficial to keep all hosts within a single local network. However, as networks grow in size, increased traffic will decrease network performance and speed. In this case, it may be beneficial to move some hosts onto a remote network.

Placing additional hosts on a remote network will decrease the impact of traffic demands. However, hosts on one network will not be able to communicate with hosts on the other without the use of routing. Routers increase the complexity of the network configuration and can introduce latency, or time delay, on packets sent from one local network to the other.