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The paper introduces a mechanism to implement distributed scheduling for CAN-bus resource in order to meet the requirements of a dynamic distributed real-time system. The key issues considered here, are multicasting, distinguishing between hard real-time, soft real-time, and non real-time constraints, achieving high resource utilization for CAN-bus, and supporting dynamic hard real-time computing by allowing dynamic reservation of communication resources. However, due to its static nature, the TDMA approach is not suitable for dynamic real-time systems. Moreover, the TDMA protocol is applied preferrably on highbandwidth busses, like Ethernet or FDDI [7][11]. The deadline-monotonic priority assignment [16] achieves meeting deadlines as guaranteed by an off-line feasibility test for a static system with periodic tasks. Although static systems can be scheduled easily by this approach, it does not allow scheduling of dynamic systems, where an offline feasibility test has incomplete knowledge about the future behavior of the system. A dynamic scheduling of CAN bus has been approached in [18]. However, this approach makes unrealistic assumptions about CANe .g. 10 Mbits/s-and exhibits a rather restricted scheduling ability due to a short time horizon (cf. section 4). In this paper, we introduce a mechanism to assign dynamic priorities to CAN messages, in order to achieve an EDF resource access consensus among the participating nodes. Our motivation is to schedule soft real-time communication optimally with EDF approach, and to guarantee deadlines of hard real-time communication by calendar-based resource reservation. As we have shown in [7], these two scheduling approachs can co-exist in CAN, if they are based on our EDF access mechanism. We take advantage of the built-in CSMA/CA access protocol of CAN bus to implement the EDF access regulation. The CSMA/CA protocol is comparable with a priority-based dispatcher. Due to this analogy, we express our scheduling decisions for the CAN-bus resource by static or dynamic priority orders. The paper is organized as follows: Section 2 introduces some features of CAN. In section 3 some of the common approaches to the CAN-bus scheduling are discussed. In Section 4 we describe our dynamic priority assignment mechanism, resulting in EDF access consensus. Based on the EDF access consensus, we introduce in section 5 a real-time scheduling approach for communication on CAN bus. A summary concludes the paper.