Automatic rate adaptation system in a local area network

Abstract

Automatic speed adaptation system in a Local Area Network (LAN) between a hub (10) including a hub adapter (20, 24, 28) and at least a workstation (12, 14, 16) including a workstation adapter (18, 22, 26) for exchanging data over a link connected between the hub adapter and the workstation adapter at a rate based on a frequency which is inversely proportional to the length of the link. Each adapter comprises a clock generator for generating a clock having a frequency between F1 and F2 and processing means for transmitting at least a check frame from the hub adapter to the workstation adapter at a rate based on a frequency VCLK generated by the clock generator under the control of the processing means and selected as being the frequency corresponding to the length of the link, and for transmitting an acknowledge frame from the workstation adapter to the hub adapter thereby ascertaining that the selected frequency is the right frequency resulting in the best quality of transmission.

Dependencies are inferred from the claim text.