Reliability and Timing Analysis of Distributed systems. --- Traditionally, real-time scheduling theory has targeted hard real-timesystems which are, most of the time, safety critical. Typically, thesesystems can be found as small embedded applications, operated in acontrolled environment. Since these systems are not allowed to have any flaws (in the sence of timliness), analysis thechniques need to be precise. Having precise methods, taking all possible scenarios of execution combinations and execution times into consideration, the analysis becomes very pessimistic which calls for more expensive applications in terms of resources and hardware. However, today moreand more applications have real-time demands, although not assafety-critical as traditional real-time systems, e.g. audio and video transmissions. These new applications open the door to loosen up a bit, thus allowing some deadline misses every now and then. We call this controlled optimism. By using distributions of values instead of worst-case values, designers are given more freedom in terms of arguments for making well founded trade-offs when designing anapplication. We define this as the first problem. Moreover, traditionally scheduling paradigms can be divided into 3 different groups: (1) PRIORITY DRIVEN, (2) TIME DRIVEN, and (3) SHARE DRIVEN. For the Controller Area Network, priority driven scheduling is the natural scheduling method supportedby the CAN protocol, and scheduling analysis methods have been presented. Regarding time driven sceduling, methods have also been implemented. One of those methods also supports priority driven scheduling in combination with time driven scheduling. However, yet so far, share driven scheduling has notbeen implemented. By providing the option of share driven scheduling of the CAN we believe that designers are given more freedom in designing an application. This is our second problem. Therefore, the problems that we try to solve are described in two parts: (1) Probabilistic modelling of thebit-stuffing mechanism of the Controller Area Network (CAN), and (2)Server based scheduling of CAN.
[Show all publications]
Server-Based Scheduling of the CAN Bus
(Sep 2003) Thomas Nolte, Mikael Sjödin, Hans Hansson Proceedings of the 9th IEEE International Conference on Emerging Technologies and Factory Automation (ETFA03)
Using Servers to Provide Bandwidth Isolation on the Controller Area Network
(Jun 2003) Thomas Nolte, Mikael Sjödin, Hans Hansson Proceedings of the 2nd International Workshop on Real-Time Lans in the Internet Age (RTLIA03) in conjunction with the 15th Euromicro International Conference on Real-Time Systems (ECRTS03)
Probabilistic Worst-Case Response-Time Analysis for the Controller Area Network
(May 2003) Thomas Nolte, Hans Hansson, Christer Norström Proceedings of the 9th IEEE Real-Time and Embedded Technology and Applications Symposium (RTAS03)
Reducing Pessimism and Increasing Flexibility in the Controller Area Network
(May 2003) Thomas Nolte
Server-Based Scheduling of the CAN Bus
(Apr 2003) Thomas Nolte, Mikael Sjödin, Hans Hansson
Providing Bandwidth Isolation on the Controller Area Network by Using Servers
(Apr 2003) Thomas Nolte, Mikael Sjödin, Hans Hansson