Hierarchical Scheduling of CAN using Server-Based Techniques

Server-based scheduling of CAN has been proposed as a way of fair scheduling of the Controller Area Network (CAN). By separating streams of messages by using network access servers (N-Servers), scheduling is performed at three layers where native CAN message arbitration is the scheduling at the lowest level. On top of this is the server-based scheduling to separate different streams of messages within the system. Looking at a single N-Server, several streams might share one server. Hence, scheduling is performed at the third level every time the N-Server is being scheduled for message transmission. Here different queuing policies play a role in the scheduling performed. This paper discusses the hierarchical scheduling of CAN, as a way of fair separation of message streams while providing a flexible core mechanism, the serverbased scheduling of CAN.