Towards transactional integrity issues in policy based network management systems

As networks increase in size, heterogeneity, complexity and pervasiveness, effective management of such networks becomes more important and increasingly difficult. In this context, PBNM (Policy-Based Network Management) has been gaining popularity in the recent years. New demands on internetworking, services specification, QoS and generically on network management functionality have been driving users to consider this paradigm in their own networks. As people start exploiting PBNM, another aspect comes to attention: transactional integrity. Transactional control envisages achieving consistent state changes along the network. In other words, state transition in network devices is only authorized if all the related operations are successfully taken. In this paper we propose a transactional control mechanism for PBNM systems, namely its assurance across different systems and different network domains

Towards transcactional integrity issues in policy based network management systems

As networks increase in size, heterogeneity, and complexity, their effective management becomes more important and increasingly difficult. In this context, Policy-Based Network Management (PBNM) has been gaining popularity in recent years. New demands on internetworking, services specification, Quality Service (QoS) and on network management functionality, in general, have been driving users to consider this paradigm in their own networks. From the moment PBNM pearadigms began to be implemented, another aspect became readily evident: that of transactional integrity. Transactional control envisages achieving consistent state changes along the network. In other words, state transition in network devices is only authorized if all the related operations are successfully executed. In this paper we propose a transactional control mechanism for PBNM systems, specifically a transactional control assurance across different systems and different network domains

Tuning active monitoring in multiservice IP networks

Comunicação apresentada "Performance Modelling and Evaluation of Heterogeneous Networks (HET-Nets 04), 2, Ilkley, U.K., July 2004.This paper explores the use of edge-to-edge active monitoring to control simultaneously multiple QoS parameters in multi-service IP networks, while reducing the effects of intrusion on real traffic. Considering a multi-class domain where traffic is controlled at network boundaries based on feedback from on-line measurements, the present work is centered on obtaining adequate per class in-band probing streams so that each class behaviour is correctly captured, even if more than a QoS metric is under control. In this way, we investigate distinct properties of probing patterns and cross-check probing and passive measurement results in order to assess and tune probing effectiveness. To enhance probing ability to sense multiple metrics, we explore Active Queue Management effects on probes and their different probability of reaching the network boundary. The results show that, while IPTD can be easily captured using a very low probing rate, matching ipdv and IPLR is not straightforward. However, we found that choosing a convenient drop precedence for probing packets, the simultaneous estimation of these QoS metrics can be significantly improved

Анализ применимости методов обеспечения QoS для повышения производительности мобильной радиосети специального назначения

Классификация и анализ известных методов обеспечения QoS с точки зрения целесообразности их применения для увеличения производительности мобильной радиосети специального назначенияyesБелгородский государственный университе

Proportional bandwidth distribution in IP networks implementing the assured forwarding PHB

Recent demands for new applications are giving rise to an increasing need of Quality of Service (QoS). Nowadays, most IP-based networks tend to use the DiffServ architecture to provide end-to-end QoS. Traffic conditioners are a key element in the deployment of DiffServ. In this paper, we introduce a new approach for traffic conditioning based on feedback signaling among boundary nodes and traffic conditioners. This new approach is intended to provide a poportional distribution of excess bandwidth to endusers. We evaluate through extensive simulations the performance of our proposal in terms of final throughput, considering contracted target rates and distribution of spare bandwidth. Results show a high level of fairness in the excess bandwidth allocation among TCP sources under different network conditions

Going beyond diffServ in IP traffic classification

Quality of Service (QoS) management in IP networks today relies on static configuration of classes of service definitions and related forwarding priorities. Packets are actually classified according to the DiffServ architecture based on the RFC 4594, typically thanks to static configuration or filters matching packet features, at network access equipment. In this paper, we propose a dynamic classification procedure, referred to as Learning-powered DiffServ (L-DiffServ), able to detect the distinctive characteristics of traffic and to dynamically assign service classes to IP packets. The idea is to apply semi-unsupervised Machine Learning techniques, such as Linear Discriminant Analysis (LDA) and K-Means, with a proper customization to take into account the issues related to packet-level analysis, i.e. unbalanced distribution of traffic among classes and selection of proper IP header related features. The performance evaluation highlights that L-DiffServ is able to change dynamically the classification outcome, providing an higher number of classes than DiffServ. This last result represents the first step toward a more granular differentiation of IP traffic

Selected Issues of QoS Provision in Heterogenous Military Networks

Tactical ad-hoc networks are evolving today towards complex heterogeneous networks in terms of architecture, protocols and security. Due to the difference in network resources and reliability, end-to-end quality of service provisioning becomes very challenging. If we also take into account communication issues such as unpredictable connectivity, preferential forwarding for special traffic classes, intermittency due to node or communication link failure, the problem is further aggravated.In this article, we examine the major challenges that must be solved in order to provide efficient QoS provisioning in the heterogeneous network. Finally we describe QoS-aware mechanisms for inter-domain and intra-domain heterogeneous networks, also including real-time services provision in highly mobile environments.

Achieving bounded delay on message delivery in publish/subscribe systems

2006-2007 > Academic research: refereed > Refereed conference paperVersion of RecordPublishe