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Introduction 3
Figure 1.2: Protocol overhead in the OSI model
1.2 LAN
A local network (Local Area Network (LAN)) has been developed to ensure communication
between computers, work stations and peripherals in an area of a very limited geographical
size.
The connected stations in a LAN are autonomous, meaning that primary and secondary stations
do not exist. Every station can set up, maintain and break off a connection with another
station. With regard to public networks, the four bottom layers of the OSI model require a
slightly different approach for a LAN.
The 802 committee of the Institute for Electrical and Electronic Engineers has established a
number of standards for LANs.
Figure 1.3: Location LAN within the OSI model
Figure ?? shows the filling in of layers 1 and 2 in the OSI model by the IEEE802 standard.
Standard IEEE802.1 can be consulted for general concept on LANs.
Currently, the following work groups are active within the IEEE802 committee:
• IEEE802.1 Bridging (networking) and Network Management