Network Access Layer (1): Wired LAN Technologies

mLocal networks - so-called LANs (Local Area Networks) connect computers that are in close proximity to each other. The triumphant march of LANs remains unbroken, extending from a simple point-to-point connection between two computers in the same room, to company/campus networks linking several hundred or even thousands of computers all communicating with each other over a common transmission medium. In respect to their geographical scope and the number of computers that can be connected over them, LANs, however, do have technical limitations. Different operational criteria, such as cost, throughput rate, spatial expansion and arrangement have led to the development of widely varying LAN technologies. These all follow their own protocol mechanisms and are each suited for application in different scenarios whether stationary or mobile.For the manufacturer as well as for the user, the necessity of a standardization was an urgent matter. Under the umbrella of the organization IEEE, the IEEE 802 chapter has been formed with its respective working groups. This chapter has created standards for widespread LAN technologies such as Ethernet, token ring, or the indispensable WLAN, and continues to develop them further. We will look at the development of various technologies and describe standards in the area of the local network. The topics covered range from thematic classification in the TCP/IP reference model to protocol mechanisms, address management in the LAN, to a description of various LAN technologies. The focus of here will be on wired LAN technologies. Due to its growing importance, a separate chapter has been dedicated to wireless LAN.