Media bus interface arbitration for a data server

Abstract

A data server for use in networks where media data are transmitted in packet form comprises at least one card shelf containing at least a bus controller card, a plurality of media processor cards, and a backplane. The backplane has a plurality of media buses, which carry data in packet form among the cards installed on the shelf. Each card has at least one bidirectional port with its own unique identity, and each bidirectional port outputs flow control information as to whether that port can or cannot accept packets of data that are intended to be sent to it, as well as transmit requests to transmit packets of data from that port. Each card outputs flow control information for each bus. A bus arbiter reviews each request to transmit and each flow control message, and grants requests to transmit media data packets only when the intended destination address is free to receive a media data packet over a free bus. Priority may be assigned to each data packet; and a processing algorithm in the bus arbiter determines the order of processing requests to transmit packets of data, and balances the priorities of ports and cards, and their respective requests.