in ieee project 802 logic link control (llc) is used to control and handle the
Logical link control In the IEEE 802 reference model of computer networking, the logical link control (LLC) data communication protocol layer is the upper sublayer of the data link layer (layer 2) of the seven-layer OSI model. The LLC sublayer provides multiplexing mechanisms that make it possible for several network protocols (e.g. IP, IPX, Decnet and Appletalk) to coexist within a multipoint network and to be transported over the same network medium. It can also provide flow control and automatic repeat request (ARQ) error management mechanisms.
OSI model The concept of a seven-layer model was provided by the work of Charles Bachman at Honeywell Information Services. Various aspects of OSI design evolved from experiences with the ARPANET, NPLNET, EIN, CYCLADES network and the work in IFIP WG6.1. The new design was documented in ISO 7498 and its various addenda. In this model, a networking system was divided into layers. Within each layer, one or more entities implement its functionality. Each entity interacted directly only with the layer immediately beneath it, and provided facilities for use by the layer above it.