FlexRay is a communication system that will support the needs of future in-car control applications. At the core of the FlexRay system is the FlexRay communications protocol. The protocol provides flexibility and determinism by combining a scalable static and dynamic message transmission, incorporating the advantages of familiar synchronous and asynchronous protocols. The protocol also supports:

• Fault-tolerant clock synchronization via a global time base
• Collision-free bus access
• Guaranteed message latency
• Message oriented addressing via identifiers
• Scalable system fault-tolerance via the support of either single or dual channels

A physical layer incorporating an independent Bus Guardian provides further support for error containment. The FlexRay system is targeted to support a data rate of 10Mbit/sec with increased flexibility for easy system extension and the dynamic use of bandwidth. The 10Mbit/sec data rate is available on two channels, giving a gross data rate of up to 20Mbit/sec.