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 TitleDate AddedCompany
whitepaper A Statistical Approach to Risk Mitigation in Computational Markets2007-06-29 Association for Computing Machinery
  This paper studies stochastic models to mitigate the risk of poor Quality-of-Service (QoS) in computational markets. Consumers who purchase services expect both price and performance guarantees. They need to predict future demand to budget for sustained performance despite price fluctuations. Conversely, providers need to estimate demand to price future usage. The skewed and bursty nature of demand in large-scale computer networks challenges the common statistical assumptions of symmetry, independence, and stationarity. This discrepancy leads to underestimation of investment risk. The paper confirms this non-normal distribution behavior in the study of demand in computational markets. The high agility of a dynamic resource market requires flexible, efficient, and adaptable predictions.

Tags: IT Budgeting		   
whitepaper Optimal Replica Placement in Tree Networks With QoS and Bandwidth Constraints and the Closest Allocation Policy2007-06-28 French National Institute for Research in Computer Science and Control
  This paper deals with the replica placement problem on fully homogeneous tree networks known as the Replica Placement optimization problem. The client requests are known beforehand, while the number and location of the servers are to be determined. The latter problem is investigated using the Closest access policy when adding QoS and bandwidth constraints. The paper proposes an optimal algorithm in two passes using dynamic programming.

Tags: Network Management		   
whitepaper Physical-Layer Considerations for the Realistic Deployment of Impairment-Aware Connection Provisioning2007-06-15 Institute of Electrical and Electronics Engineers
  Nowadays, impairment-aware connection provisioning is a hot topic due to the evolution of optical networks to all-optical infrastructures and to the need to maintain or enhance Quality of Service (QoS). Most of the research efforts in this field use complex, analytical models of impairments as the basis for the connection provisioning decision. However, these models are not fully feasible in practice due to cost, monitoring limitations and the architectures of impairment-aware Routing and Wavelength Assignment (RWA). This paper discusses key physical-layer considerations for the realistic deployment of impairment-aware connection provisioning, and provides an example of cost-effective, distributed Impairment-aware RWA (IRWA) in the context of the all-optical ADRENALINE testbed.

Tags: Network Management, Network Technologies		   
whitepaper Towards User-Centric Metrics for Denial-of-Service Measurement2007-06-14 Association for Computing Machinery
  To date, the measurement of user-perceived degradation of quality of service during Denial of Service (DoS) attacks remained an elusive goal. Current approaches mostly rely on lower level traffic measurements such as throughput, utilization, loss rate, and latency. They fail to monitor all traffic parameters that signal service degradation for diverse applications, and to map application Quality-of-Service (QoS) requirements into specific parameter thresholds. To objectively evaluate an attack's impact on network services, its severity and the effectiveness of a potential defense, the paper needs precise, quantitative and comprehensive DoS impact metrics that are applicable to any test scenario. The paper proposes a series of DoS impact metrics that measure the QoS experienced by end users during an attack.

Tags: Intrusion - Tampering, Intrusion - Tampering		   
whitepaper QUORUM - QUality Of Service RoUting in Wireless Mesh Networks2007-06-13 Association for Computing Machinery
  Wireless Mesh Networks (WMNs) can provide seamless broadband connectivity to network users, with the advantage of low setup and maintenance costs. To support next-generation applications with real-time requirements, however, these networks must provide improved Quality of Service guarantees. Most current mesh network routing protocols are adapted from MANET protocols, and do not optimize for mesh network properties. This paper proposes QUORUM (QUality Of service RoUting in wireless Mesh networks), a routing protocol optimized for WMNs that addresses these drawbacks. QUORUM integrates a novel end-to-end packet delay estimation mechanism with stability-aware routing policies, allowing it to more accurately follow QoS requirements while minimizing misbehavior of selfish nodes.

Tags: Network Technologies, Mobile and Wireless		   
whitepaper An Approach to Enhance the QoS Support to Real-Time Traffic on IEEE 802.11e Networks2007-06-12 Universita di Catania
  This paper proposes an approach to overcome some limitations of the 802.11e protocol highlighted in recent literature and improve the QoS support provided to real-time industrial traffic. The proposed solution does not change the IEEE 802.11e protocol, but introduces a technique to reduce the number of collisions and therefore to use the channel more efficiently for real-time traffic, especially when the traffic load is high and approaches saturation conditions. The proposed mechanism, called a Contention Window Adapter, dynamically changes the contention window size of the different Access Categories defined by the IEEE 802.11e protocol according to the wokload conditions of the wireless network. The paper describes the rationale behind the CWA mechanism, the algorithm itself and discusses the performance obtained through simulations run using ns-2.

Tags: Mobile and Wireless, Mobile and Wireless		   
whitepaper Winterthur Achieves Market Leadership in Reducing Costs and Increasing Quality With Standardized Business Processes0000-00-00 TIBCO Software
  Winterthur is the leading insurance company in Switzerland. Winterthur was looking for a comprehensive BPM system to achieve cost control in the area of pension plan management by streamlining and standardizing processes. Having implemented other types of cost reduction programs common in the industry, Winterthur wanted to identify new savings opportunities and drive margins in what is a tough competitive arena. The company saw business process optimization as the way to achieve required cost savings and to leverage technology to remain at the market's forefront. As a solution Winterthur is using TIBCO's BPM software to standardize processes relating to management of savings accounts for pension benefits.

Tags: Enterprise Planning, IT Budgeting		   
whitepaper Dynamic Re-Negotiations of SLA in Service Composition Scenarios2007-06-05 Universita di Catania
  In a SOA environment services are implemented on top of resources across different administrative domains, in which IT infrastructure and internal resources are managed according to autonomous policies. Service Providers and their customers negotiate utility based Service Level Agreements (SLA) to determine costs and penalties based on the achieved performance levels. In B2B scenarios where several service providers are involved in the composition of a service, and each of them plays both the parts of provider and customer, several one-to-one SLAs need to be signed. In such a rigid context the global QoS of the final service can be strongly affected by any violation on each single SLA.

Tags: User Satisfaction		   
whitepaper HP Disaster Proof Solutions: Ensuring Application Availability2007-06-01 Hewlett-Packard (HP)
  HP built a highly available, disaster tolerant multi-data center environment to test and demonstrate its availability and recoverability solutions. They then created a disaster that rendered the primary site immediately useless in order to show the effectiveness of the HP solution. This ESG paper provides views of the current business continuity market as well as thoughts on HP's role in the market.

ESG has found that there is an increase in the number of companies and organizations requiring 24 x 365 days of IT uptime. IN fact, ESG research indicates that 36% of enterprises indicating they will incur significant revenue loss of other adverse business impact if they have even an hour or less of downtime on their mission-critical applications. Almost 15% indicate they cannot tolerate any downtime. In the past, this type of business demand was only consigned to a relatively small group. However, many more organizations of all sizes, in all industries and located across the globe, now require applications to be running and data to be always available. The needs of these organizations go far beyond simply recovery, requiring an environment that maintains business continuity during and immediately after a disaster. To make it more interesting, the number and types of applications that require this level of protection is very diverse.

Tags: Network Management, Network Management, Data Tools, Data Infrastructure		   
whitepaper Converged Packet Architecture2007-06-01
  With the explosion of data services, most notably the Internet, and the ubiquity of Ethernet interfaces, the Time Domain Multiplexed (TDM) network-a network designed based on multiplexing of 64 KHz voice channels-is no longer optimal for the traffic it is being forced to carry. Many data services are transmitted using relatively small TDM circuits such as DS0s, Fractional DS1s (NxDS0), DS1s, and NxDS1 facilities. This is a rigid and inflexible structure that is not well suited well to the needs of data and packet services. The Converged Packet Architecture (CPA) strategy breaks the traditional tie between Layer 2 protocols and Layer 1 transport circuits and leverages the economics of the Ethernet while providing the Quality of Service (QoS) and Service Level Agreements (SLAs) expected of a carrier class service provider.

Tags: Network Management, User Satisfaction