Abstract
This paper provides an analysis of the real-time behaviour of the multi-master Profibus DP network. The analysis is based on the evaluation of the worst-case message response time and the results obtained are compared with those present in literature, pointing out its capability to perform a more accurate evaluation of the performance of the Profibus network. Copyright © 2002 IFAC.

Abstract
In this paper we address the ability of WorldFIP to cope with the real-time requirements of distributed computer-controlled systems (DCCS). Typical DCCS include process variables that must be transferred between network devices both in a periodic and sporadic (aperiodic) basis. The WorldFIP protocol is designed to support both types of traffic. WorldFIP can easily guarantee the timing requirements for the periodic traffic. However, for the aperiodic traffic more complex analysis must be made in order to guarantee its timing requirements. This paper describes work that is being carried out to extend previous relevant work, in order to include the actual schedule for the periodic traffic in the worst-case response time analysis of sporadic traffic in WorldFIP networks.

Abstract
Fieldbus communication networks aim to interconnect sensors, actuators and controllers within process control applications. Therefore, they constitute the foundation upon which real-time distributed computer-controlled systems can be implemented. P-NET is a fieldbus communication standard, which uses a virtual token-passing medium-access-control mechanism. In this paper pre-run-time schedulability conditions for supporting real-time traffic with P-NET networks are established. Essentially, formulae to evaluate the upper bound of the end-to-end communication delay in P-NET messages are provided. Using this upper bound, a feasibility test is then provided to check the timing requirements for accessing remote process variables. This paper also shows how P-NET network segmentation can significantly reduce the end-to-end communication delays for messages with stringent timing requirements.

Abstract
Monitoring applications in onshore oil and gas production environments are usually based on wireless solutions. Most part of nowadays applications rely upon outdated technologies, based on the use of analog radios and inefficient master-slave communication topologies. In this paper, we investigate the use of Wireless Sensor Network (WSN) technologies to monitor oil and gas production environments. More specifically, we consider a mesh topology for the communication network and we analyze the performance of three different routing algorithms: the classic AODV algorithm, an hierarchical routing algorithm and our own proposed version of a simplified AODV. A simulation assessment of these 3 algorithms is done using the Network Simulator NS-2, upon data from a real topology of onshore oil wells monitoring. © 2010 IEEE.

Abstract
Controller Area Network (CAN) is a fieldbus network suitable for small-scale Distributed Computer Controlled Systems, being appropriate for transferring short real-time messages. Nevertheless, it must be understood that the continuity of service is not fully guaranteed since it may be disturbed by temporary periods of network inaccessibility [1]. In this paper, such temporary periods of network inaccessibility are integrated in the response time analysis of CAN networks. The achieved results emphasise that in the presence of temporary periods of network inaccessibility, a CAN network is not able to provide different integrity levels to the supported applications, since errors in low priority messages interfere with the response time of higher priority message streams.

Abstract
The IEEE 802.11s draft standard defines a mesh network in which frame delivery is done by forwarding the frame through nodes, called Mesh Points (MPs). To make this possible, it specifies two routing protocols: HWMP and RA-OLSR. Both protocols suffer from scalability issues caused by the use of broadcast messages for discovery and update of routes. In this work, we propose a new routing protocol, the DHT-based Cluster Routing Protocol (DCRP), that improves the scalability of 802.11s networks. Our approach is based on two mechanisms: clustering of nodes and IN-IT-based searching. Clustering allows to reduce the number of broadcast messages required for routing as well as the amount of routing information broadcasted. DHT-based searching is used to make up for the required routing information that is not diffused by the DCRP itself. Some back-of-the-envelope calculations indicate that our approach increases the scalability of the routing protocol.