Before delving into the various roles that routers can play in a LAN, it is necessary to first understand some of the functional aspects of a LAN. This will make it easier to understand the effects that routers have when used in a LAN.
A LAN, at its simplest, is a data communications vehicle that operates at the physical and data link layers of the OSI reference model. LANs support two critical functions:
The capability to both address and forward frames of data to other local machines
The key word in the second item is local. The definition of local may change subtly with context: A LAN has boundaries that constrain its capability to perform these two functions. For example, a LAN has a media access domain and a Media ...