In this paper we present a prototype of the RTSC - the Real-Time System Compiler. The RTSC is a compiler-based tool that leverages the migration from event-triggered to time-triggered real-time systems. For this purpo...
详细信息
In this paper we present a prototype of the RTSC - the Real-Time System Compiler. The RTSC is a compiler-based tool that leverages the migration from event-triggered to time-triggered real-time systems. For this purpose, it uses an abstraction called Atomic Basic Blocks (ABBs) which is used to capture all relevant dependencies of the event-triggered system in a so-called ABB-graph. This ABB-graph is transformed by the RTSC and finally mapped to a statically computed schedule that could be executed by standard time-triggered real-time operatingsystems. Moreover, we demonstrate the applicability of our approach and the operation of our prototype by transforming the event-triggered implementation of a real-world embedded system into a trime-triggered equivalent.
LEDBAT is a new congestion control algorithm which was proposed in an IETF draft in March 2009. LEDBAT's goal is to provide a less-than-best-effort data transport service, i.e. a LEDBAT flow should back-off in the...
详细信息
ISBN:
(纸本)9781424467259
LEDBAT is a new congestion control algorithm which was proposed in an IETF draft in March 2009. LEDBAT's goal is to provide a less-than-best-effort data transport service, i.e. a LEDBAT flow should back-off in the presence of other competing flows (TCP flows in particular). Because of its intended friendliness to competing flows, LEDBAT has already been implemented in the popular Bittorrent client uTorrent. In this paper we present performance evaluation results for our Python implementation of LEDBAT. We ran tests both in emulated networks as well as in real world networks. One of the tests involved approximately 300 volunteers spread throughout the world.
User interaction has always been one of the most crucial points when evaluating the quality of experience of a service. Mobile television, especially when received over DVB-H or in other small bandwidth transmission e...
详细信息
Initial deployment of secrets plays a crucial role in any security design, but especially in hardware constrained wireless sensor networks. Many key management schemes assume either manually pre-installed shared secre...
详细信息
In this paper, we propose a taxonomy that characterizes and classifies different components of autonomic application management in Grids. We also survey several representative Grid systems developed by various project...
详细信息
This paper presents a group communication system for mobile devices, called distributedGCS. Mobile communication is slow, expensive and suffers from occasional disconnections, especially when users are moving. Distrib...
详细信息
This paper tries to give an overview of the rising concerns raised by the of privacy protection that is associated with the European Data Retention Directive. After relating this risk to the requirements as stated in ...
详细信息
In a Cell-based cluster, vector units are used as accelerators for compute-intensive tasks to provide high performance. Currently, direct communication between vector units on different cluster nodes is not supported....
详细信息
ISBN:
(纸本)9780889868786
In a Cell-based cluster, vector units are used as accelerators for compute-intensive tasks to provide high performance. Currently, direct communication between vector units on different cluster nodes is not supported. The overall inter-node communication bandwidth is reduced by the fact that the general- purpose processor is responsible for sending and/or receiving data on behalf of the vector units over the InfiniBand network. Thus a reduction of the communication latencies can be achieved through direct access to the InfiniBand network for the vector units without involvement of the general-purpose core. This work focusses on the design of a strategy to build an effective inter-node communication scheme between the vector units over InfiniBand and the implementation of a library which allows direct access for the vector units to the InfiniBand network.
P2P systems can benefit from reputation mechanisms to promote cooperation and help peers to identify good service providers. However, in spite of a large number of proposed reputation mechanisms, few have been investi...
详细信息
P2P systems can benefit from reputation mechanisms to promote cooperation and help peers to identify good service providers. However, in spite of a large number of proposed reputation mechanisms, few have been investigated in real situations. BarterCast is a distributed reputation mechanism used by our Internet-deployed Bittorent-based file-sharing client Tribler. In BarterCast, each peer uses messages received from other peers to build a weighted, directed subjective graph that represents the upload and download activity in the system. A peer calculates the reputations of other peers by applying the maxflow algorithm to its subjective graph. For efficiency reasons, only paths of at most two hops are considered in this calculation. In this paper, we identify and assess three potential modifications to BarterCast for improving its accuracy and coverage (fraction of peers for which a reputation value can be computed). First, a peer executes maxflow from the perspective of the node with the highest betweenness centrality in its subjective graph instead of itself. Second, we assume a gossiping protocol that gives each peer complete information about upload and download activities in the system, and third, we lift the path length restriction in the maxflow algorithm. To assess these modifications, we crawl the Tribler network and collect the upload and download actions of the peers for three months. We apply BarterCast with and without the modifications on the collected data and measure accuracy and coverage.
Community Health Information Tracking System using Short Message Service (chitSMS) is an extension of CHITS which is a system that stores health records of patients in the barangay. Another project incorporated a mobi...
详细信息
Community Health Information Tracking System using Short Message Service (chitSMS) is an extension of CHITS which is a system that stores health records of patients in the barangay. Another project incorporated a mobile component in CHITS, enabling the health worker to visit the patient, do routine check-ups and medical services, and update CHITS when the health worker returns to the health center. Without a remote connection, however, the health worker has to return frequently to the usually distant health center to update the CHITS database with the data gathered from the field consult. chitSMS addresses this by using SMS as a mode of remote data transfer. It ensures the reliable transmission of the data by implementing a modified selective repeat protocol. Furthermore, it performs the Deflate algorithm for compression of the data being sent to minimize the cost.
暂无评论