Modern distributed control systems comprise multiple intelligent devices capable of performing complex time and mission-critical tasks both independently of each other or partly jointly with each other. To do so, they strongly depend on an accurate common notion of time as well as a reliable shared communication medium for timely data exchange. Traditional legacy communication technologies (field bus systems) supported time transport to a certain extent or provided at least a common frequency. Due to its numerous undisputed advantages, Ethernet has become the only viable communication medium effectively replacing such systems. Being inherently asynchronous time and frequency transfer has to be accomplished using a packet-based approach when moving to Ethernet. After explaining the basic principles of packet-based time transfer, the most common standards are explained compared with each other with respect to their intended application domains. Special emphasis will be put on the Precision Time Protocol (PTP) as defined in the underlying IEEE 1588 standard and its variant IEEE 802.1AS used for time-sensitive networks. Maintaining a highly accurate common notion of time under all circumstances is a crucial prerequisite for most distributed systems. Although PTP has proven to provide sub-microsecond accuracies, it can cope only with a limited number of error conditions. This paper describes all major sources that can either deteriorate the accuracy or cause a total loss of synchronization altogether. Selected countermeasures and enhancements are presented, which can greatly improve the resilience of PTP against errors as well as malicious attacks. This paper concludes by presenting the selected measurements' results of a novel proposed method.

Nowadays, multiple sensor nodes are often incorporated into technical solutions forming distributed sensor systems. Herein, advanced detection mechanisms are often realised by using data from multiple sensors in such a network. However, sometimes active sensors - like Time-Of-Flight cameras - interfere with each other. To solve this problem and assist in data correlation, a clock synchronisation method, like IEEE1588, can be adapted. Although, if the sensor nodes have not been developed with this in mind they have to be refitted. An optimal refit of a system is the one that needs the least modifications necessary to achieve the desired goal. This paper lists the impact - in terms of jitter and asymmetry - that different components of a system have on IEEE1588 synchronisation precision and methods to eliminate or alleviate jitter and asymmetry sources in order to enable respective sensor fusion.

This work describes a flexible gateway platform for automotive networks which is currently developed at the University of Applied Sciences Technikum Wien. In contrast to most available gateways the platform described herein can be configured and expanded to a high degree concerning both hardware and software by using a programmable system-on-chip architecture. The proposed solution is not limited to gateway applications but provides a generic platform for the development of network infrastructure in the automotive area.