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91.
In this paper we explore the interest of computational intelligence tools in the management of heterogeneous communication networks, specifically to predict congestion, failures and other anomalies in the network that may eventually lead to degradation of the quality of offered services. We show two different applications based on neural and neuro-fuzzy systems for quality of service (QoS) management in next generation networks for voice and video service over heterogeneous Internet protocol (V2oIP) services. The two examples explained in this paper attempt to predict the communication network resources for new incoming calls, and visualizing the QoS of a communication network by means of self-organizing maps. 相似文献
92.
Minhong Wang Huaiqing Wang Doug Vogel Kuldeep Kumar Dickson K.W. Chiu 《Engineering Applications of Artificial Intelligence》2009,22(7):1046-1055
Modern businesses are facing the challenge of effectively coordinating their supply chains from upstream to downstream services. It is a complex problem to search, schedule, and coordinate a set of services from a large number of service resources under various constraints and uncertainties. Existing approaches to this problem have relied on complete information regarding service requirements and resources, without adequately addressing the dynamics and uncertainties of the environments. The real-world situations are complicated as a result of ambiguity in the requirements of the services, the uncertainty of solutions from service providers, and the interdependencies among the services to be composed. This paper investigates the complexity of supply chain formation and proposes an agent-mediated coordination approach. Each agent works as a broker for each service type, dedicated to selecting solutions for each service as well as interacting with other agents in refining the decision making to achieve compatibility among the solutions. The coordination among agents concerns decision making at strategic, tactical, and operational level. At the strategic level, agents communicate and negotiate for supply chain formation; at the tactical level, argumentation is used by agents to communicate and understand the preferences and constraints of each other; at the operational level, different strategies are used for selecting the preferences. Based on this approach, a prototype has been implemented with simulated experiments highlighting the effectiveness of the approach. 相似文献
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无线多媒体传感器网络(WMSNs)的主要特点包括资源有限、时延敏感和数据冗余性高。此外,音视频数据流传输所需的带宽是多媒体传感器节点所能承受的最大传输带宽的几倍。上述因素使得WMSNs的QoS 路由成为一个亟待解决的关键技术问题。鉴于此,首先通过基于等差数列的非均匀分簇算法对网络区域进行划分,然后在此网络拓扑上,提出一种基于移动Agent的WMSNs的QoS路由算法(MAQR)。MAQR由路由发现和数据传输两个阶段组成。在路由发现阶段,采用移动代理技术完成多路径路由发现。在数据传输阶段,采用多优先级多路径传输模型把数据流进行分类,并利用流量预测算法实现网络的负载均衡。最后,在NS-2平台上实现了MAQR,通过与同类算法进行仿真比较,发现MAQR较之同类算法能够明显地提高音视频传输的服务质量。此外,MAQR算法比同类算法的能耗更低。 相似文献
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服务组合基于多种基本的组合结构,组合多个已有的服务来满足用户的功能性和非功能性(即QoS)需求。通常,用户的需求直接是端到端的需求,而服务描述本身具有自身的QoS描述。由于所处的层次不同,端到端的QoS需求描述和单个服务的QoS描述存在一定的语义鸿沟。基于层次化本体模型建立QoS本体模型,建立了用户QoS和服务QoS之间的映射关系。并针对基本的服务组合结构,研究了异构QoS本体环境下服务的QoS聚合机制。基于基本组合结构的QoS聚合,提出了完整的服务组合中的QoS聚合算法和QoS转换算法,以满足端到端的QoS需求。 相似文献
100.
Vittorio Ghini Stefano Ferretti Fabio PanzieriAuthor vitae 《Journal of Systems and Software》2011,84(11):1827-1851
This paper presents a distributed architecture for the provision of seamless and responsive mobile multimedia services. This architecture allows its user applications to use concurrently all the wireless network interface cards (NICs) a mobile terminal is equipped with. In particular, as mobile multimedia services are usually implemented using the UDP protocol, our architecture enables the transmission of each UDP datagram through the “most suitable” (e.g. most responsive, least loaded) NIC among those available at the time a datagram is transmitted. We term this operating mode of our architecture Always Best Packet Switching (ABPS). ABPS enables the use of policies for load balancing and recovery purposes. In essence, the architecture we propose consists of the following two principal components: (i) a fixed proxy server, which acts as a relay for the mobile node and enables communications from/to this node regardless of possible firewalls and NAT systems, and (ii) a proxy client running in the mobile node responsible for maintaining a multi-path tunnel, constructed out of all the node's NICs, with the above mentioned fixed proxy server. We show how the architecture supports multimedia applications based on the SIP and RTP/RTCP protocols, and avoids the typical delays introduced by the two way message/response handshake of the SIP signaling protocol. Experimental results originated from the implementation of a VoIP application on top of the architecture we propose show the effectiveness of our approach. 相似文献