Showing papers on "Service level published in 2005"

Method and apparatus for dynamically adjusting resources assigned to plurality of customers, for meeting service level agreements (SLAs) with minimal resources, and allowing common pools of resources to be used across plural customers on a demand basis

Abstract: A method (and system) for managing and controlling allocation and de-allocation of resources based on a guaranteed amount of resource and additional resources based on a best effort for a plurality of customers, includes dynamically allocating server resources for a plurality of customers, such that the resources received by a customer are dynamically controlled and the customer receives a guaranteed minimum amount of resources as specified under a service level agreement (SLA).

QoS-aware replanning of composite Web services

Abstract: Run-time service discovery and late-binding constitute some of the most challenging issues of service-oriented software engineering. For late-binding to be effective in the case of composite services, a QoS-aware composition mechanism is needed. This means determining the set of services that, once composed, not only will perform the required functionality, but also will best contribute to achieve the level of QoS promised in service level agreements (SLAs). However, QoS-aware composition relies on estimated QoS values and workflow execution paths previously obtained using a monitoring mechanism. At run-time, the actual QoS values may deviate from the estimations, or the execution path may not be the one foreseen. These changes could increase the risk of breaking SLAs and obtaining a poor QoS. Such a risk could be avoided by replanning the service bindings of the workflow slice still to be executed. This paper proposes an approach to trigger and perform composite service replanning during execution. An evaluation has been performed simulating execution and replanning on a set of composite service workflows.

Households’ Willingness to Pay for Water Service Attributes

Abstract: Water consumption and disposal are often taken for granted as essential services with required levels of service quality, yet little is known about how much consumers are willing to pay for specific service levels. As customers in many countries face changing levels of water availability (especially shortages linked possibly to climate change and limited catchment capacity), the need to assess the value (and hence benefit) to society of varying service levels and prices in an effort to secure the provision of and disposal of water has risen on public agendas. In an attempt to establish how much customers are willing to pay for specific levels of service, we use a series of stated choice experiments and mixed logit models to establish the willingness to pay to avoid interruptions in water service and overflows of wastewater, differentiated by the frequency, timing and duration of these events. The empirical evidence is an important input into the regulatory process for establishing service levels and tariffs, as well as useful planning information for agencies charged with finding cost effective ways of delivering services at prices that customers deem to be value for money.

A hybrid genetic algorithm for production and distribution

Abstract: This paper develops a hybrid genetic algorithm for production and distribution problems in multi-factory supply chain models. Supply chain problems usually may involve multi-criterion decision-making, for example operating cost, service level, resources utilization, etc. These criteria are numerous and interrelated. To organize them, analytic hierarchy process (AHP) will be utilized. It provides a systematic approach for decision makers to assign weightings and relate them. Meanwhile, genetic algorithms (GAs) will be utilized to determine jobs allocation into suitable production plants. Genetic operators adopted to improve the genetic search algorithm will be introduced and discussed. Finally, a hypothetical production–distribution problem will be solved by the proposed algorithm. The optimization results show that it is reliable and robust.

An Empirical Analysis of Forecast Sharing in the Semiconductor Equipment Supply Chain

Abstract: We study the demand forecast-sharing process between a buyer of customized production equipment and a set of equipment suppliers. Based on a large data collection we undertook in the semiconductor equipment supply chain, we empirically investigate the relationship between the buyer's forecasting behavior and the supplier's delivery performance. The buyer's forecasting behavior is characterized by the frequency and magnitude of forecast revisions it requests (forecast volatility) as well as by the fraction of orders that were forecasted but never actually purchased (forecast inflation). The supplier's delivery performance is measured by its ability to meet delivery dates requested by the customers. Based on a duration analysis, we are able to show that suppliers penalize buyers for unreliable forecasts by providing lower service levels. Vice versa, we also show that buyers penalize suppliers that have a history of poor service by providing them with overly inflated forecasts.

Service Level Agreement based Allocation of Cluster Resources: Handling Penalty to Enhance Utility

Abstract: Jobs submitted into a cluster have varying requirements depending on user-specific needs and expectations. Therefore, in utility-driven cluster computing, cluster resource management systems (RMSs) need to be aware of these requirements in order to allocate resources effectively. Service level agreements (SLAs) can be used to differentiate different value of jobs as they define service conditions that the cluster RMS agrees to provide for each different job. The SLA acts as a contract between a user and the cluster whereby the user is entitled to compensation whenever the cluster RMS fails to deliver the required service. In this paper, we present a proportional share allocation technique called LibraSLA that takes into account the utility of accepting new jobs into the cluster based on their SLA. We study how LibraSLA performs with respect to several SLA requirements that include: (i) deadline type whether the job can be delayed, (ii) deadline when the job needs to be finished, (iii) budget to be spent for finishing the job, and (iv) penalty rate for compensating the user for failure to meet the deadline

Competitive Tendering as a Contracting Mechanism for Subsidising Transport

Abstract: Competitive tendering (CT) is a popular mechanism for the provision of transport services where a major objective is the containment of the cost to government of service provision. Although the primary focus is recognised as cost efficiency, whereby the cost outcome should be conditional on a given level of service, difficulties in establishing appropriate tests for service level compliance has become a cause of concern regarding the effectiveness of the CT paradigm as a value for money initiative. This paper reviews the international successes and failures of CT as a subsidy reduction strategy within the bus sector, and promotes the idea of Performance Based Contracts as a way of recognising the real role of subsidy under the umbrella of a value for money objective.

An asynchronous router for multiple service levels networks on chip

Abstract: Networks on chip that can guarantee quality of service (QNoC) are based on special routers that can support multiple service levels. GALS SoCs call for asynchronous NoC implementations, to eliminate the need for synchronization when crossing clock domains. An asynchronous multi-service level QNoC router is investigated. It comprises multiple interconnected input and output ports, and arbitration mechanisms that resolve any output port and service level conflicts. Buffering and credit based transport are enabled, enhancing throughput. A synchronous and an asynchronous router have been designed, and their performance is compared. The asynchronous router requires less area and enables a higher data rate.

Internal service quality: Determinants of distribution center performance

Abstract: Purpose – This work seeks to examine how front‐line employee performance and interdepartmental customer orientation affect the service, supply chain, and financial performance of US distribution centers.Design/methodology/approach – The authors approached this subject by utilizing works from the supply chain management, services marketing, total quality management, and logistics personnel literature. Surveys were administered in 18 distribution centers across the USA and canonical correlation was employed to test the propositions that front‐line employee performance and interdepartmental customer orientation have a positive effect on distribution center service, supply chain, and financial performance.Findings – Findings indicate that high levels of front‐line employee performance and interdepartmental customer orientation a positive effect on distribution center service and supply chain performance. The relationship of the two independent variables to distribution center financial performance was only pa...

Method and system for imposing air interface service level

Abstract: A method and system for providing services in communications networks. A gateway layer determines information about a communication session and responsively sends a signaling message to a session manager, providing the information. The session manager may then send a signaling message to a service agent, also providing the information. The service agent may in turn apply a set of service logic based at least in part on the information, so as to derive a service treatment, and the service agent may send a signaling message so as to cause an enforcement engine (such as the gateway or session manager) to carry out the service treatment. Advantageously, this arrangement may facilitate imposition of services across various types of communication sessions (such as voice sessions and/or data sessions) and access networks (such as circuit-switched and/or packet-switched), at session initiation and during the course of an ongoing session. A variety of useful services may thereby be provided.

System and Method for Managing the Configuration of Resources in an Enterprise

Abstract: System and method for managing the configuration of resources in an enterprise. Embodiments of the present invention gather, store, and maintain institutional knowledge of configurations of IT resources of an enterprise. A configuration database serves as a temporal record of the configurations of the resources. The configuration database can reflect a dimensional model of the enterprise configuration where various configuration items are linked together. A configuration change can be analyzed and approved, and then reflected in a change to a configuration item (CI) which imposes an appropriate change to other configuration items based on upstream, downstream, peer relationships and/or views. A system according to an embodiment of the invention can also include a change database, an inventory database, a problem database, and/or a service level management subsystem to ensure changes to an enterprise's configuration are consistent with service level agreements and/or operating level agreements.

A Business Driven Management Framework for Utility Computing Environments

Abstract: In this paper, we introduce a Business Driven Framework for the Management of Utility Computing Environments (BDMF). The framework couples two main subsystems on top of an IETF-like policy-based resource control layer. They are MBO (Management by Business Objectives) where the decision ability supported by analysis of business objectives resides, and GSLA (Generalized SLA), an advanced framework for SLA driven management that lends itself quite naturally to the derivation of IT management policies from the SLAs that the enterprise has contracted. We discuss the advantages and the limitations of the state-of-art policy-based approach to systems management, mainly the lack of business and service level context to drive policy-related decisions at system run-time. We then explain how this is remedied in our framework through the interaction mechanism between the reactive policy-based resource control layer and the more proactive business driven decision-making engine.

Optimizing public transit quality and system access: the multiple-route, maximal covering/shortest-path problem

Abstract: Public transit service is a promising travel mode because of its potential to address urban sustainability. However, current ridership of public transit is very low in most urban regionsˆ particularly those in the United States. Low transit ridership can be attributed to many factors, among which poor service quality is key. Transit service quality may potentially be improved by decreasing the number of service stops, but this would be likely to reduce access coverage. Improving transit service quality while maintaining adequate access coverage is a challenge facing public transit agencies. In this paper we propose a multiple-route, maximal covering/shortest-path model to address the trade-off between public transit service quality and access coverage in an established bus-based transit system. The model is applied to routes in Columbus, Ohio. Results show that it is possible to improve transit service quality by eliminating redundant or underutilized service stops.

Adaptive inventory control models for supply chain management

Abstract: Uncertainties inherent in customer demands make it difficult for supply chains to achieve just-in-time inventory replenishment, resulting in loosing sales opportunities or keeping excessive chain-wide inventories. In this paper, we propose two adaptive inventory-control models for a supply chain consisting of one supplier and multiple retailers. The one is a centralized model and the other is a decentralized model. The objective of the two models is to satisfy a target service level predefined for each retailer. The inventory-control parameters of the supplier and retailers are safety lead time and safety stocks, respectively. Unlike most extant inventory-control approaches, modelling the uncertainty of customer demand as a statistical distribution is not a prerequisite in the two models. Instead, using a reinforcement learning technique called action-value method, the control parameters are designed to adaptively change as customer-demand patterns changes. A simulation-based experiment was performed to compare the performance of the two inventory-control models.

GRUBER: a grid resource usage SLA broker

Abstract: Resource sharing within grid collaborations usually implies specific sharing mechanisms at participating sites. Challenging policy issues can arise in such scenarios that integrate participants and resources spanning multiple physical institutions. Resource owners may wish to grant to one or more virtual organizations (VOs) the right to use certain resources subject to local usage policies and service level agreements, and each VO may then wish to use those resources subject to its usage policies. This paper describes GRUBER, an architecture and toolkit for resource usage service level agreement (SLA) specification and enforcement in a grid environment, and a series of experiments on a real grid, Grid3. The proposed mechanism allows resources at individual sites to be shared among multiple user communities.

A coordination framework for supply chain inventory alignment

Abstract: Purpose – A traditional supply chain, all too often, is a sequence of weakly connected activities both within and outside the organization and leads to many misalignments. Tackling this inherent lack of coordination is a major value creation opportunity for supply chain managers. This paper aims to present a coordination framework, called ASCEND, to align the inventory decisions in decentralized supply chains.Design/methodology/approach – The framework rests on three pillars – multi‐agent technology, coordination theory, and optimization technology. Inventory alignment is transformed into a decentralized constraint satisfaction optimization problem, which is then solved using a genetic algorithm‐based coordination process. The guiding principle of this framework is the establishment of a proper incentive alignment mechanism through cost‐sharing and service level contracts, taking into account the associated dependencies.Findings – The results of the pilot study indicate that the coordination framework red...

Transshipment through crossdocks with inventory and time windows

Abstract: The supply chain between manufacturers and retailers always includes transshipments through a network of locations. A major challenge in making demand meet supply has been to coordinate transshipment activities across the chain aimed at reducing costs and increasing service levels in the face of a range of factors, including demand fluctuations, short lead times, warehouse limitations and transportation and inventory costs. The success in implementing push-pull strategies, when firms change from one strategy to another in managing the chain and where time lines are crucial, is dependent on adaptive transshipment scheduling. Yet again, in transshipment through crossdocks, where just-in-time objectives prevail, precise scheduling between suppliers, crossdocks and customers is required to avoid inventory backups or delays.

Hierarchical model-based autonomic control of software systems

Abstract: Various control algorithms are used in autonomic control to maintain Quality of Service (QoS) and Service Level Agreements (SLAs). Controllers are all based to some extent on models of the relationship between resources, QoS measures, and the workload imposed by the environment. This work discusses the range of algorithms with an emphasis on richer and more powerful models to describe non-linear performance relationships, and strong interactions among the system resources. A hierarchical framework is described which accommodates different scopes and timescales of control actions, and different control algorithms. The control algorithms and architectures can be considered in three stages: tuning, load balancing and provisioning. Different situations warrant different solutions, so this work shows how different control algorithms and architectures at the three stages can be combined to fit into different autonomic environments to meet QoS and SLAs across a large variety of workloads.

Multitiered Supply Chain Networks: Multicriteria Decision—Making Under Uncertainty

Abstract: In this paper, we present a supply chain network model with multiple tiers of decision-makers, consisting, respectively, of manufacturers, distributors, and retailers, who can compete within a tier but may cooperate between tiers. We consider multicriteria decision-making for both the manufacturers and the distributors whereas the retailers are subject to decision-making under uncertainty since the demands associated with the product are random. We derive the optimality conditions for the decision-makers, establish the equilibrium conditions, and derive the variational inequality formulation. We then utilize the variational inequality formulation to provide both qualitative properties of the equilibrium product shipment, service level, and price pattern and to propose a computational procedure, along with convergence results. This is the first supply chain network model to capture both multicriteria decision-making and decision-making under uncertainty in an integrated equilibrium framework.

Reputation-Based service level agreements for web services

Abstract: Most web services need to be contracted through service level agreements that typically specify a certain quality of service (QoS) in return for a certain price. We propose a new form of service level agreement where the price is determined by the QoS actually delivered. We show that such agreements make it optimal for the service provider to deliver the service at the promised quality. To allow efficient monitoring of the actual QoS, we introduce a reputation mechanism. A scoring rule makes it optimal for the users of a service to correctly report the QoS they observed. Thus, we obtain a practical scheme for service-level agreements that makes it uninteresting for providers to deviate from their best effort.

System and method for analyzing and coordinating Service-Level-Agreements (SLA) for Application-Service-Providers (ASP)

Abstract: The present invention describes a system for automatically monitoring and managing Service Level Agreements on behalf of Service providers (such as Application Service providers) The system is based on a specialized SLA language that can translate complex or simple Service Level Agreements into measurable and controllable criterion The system enables Application Service providers to set up customized Service Level Agreements with customers, and monitor, modify and control all aspects of these agreements, including billing, sales, Customer Relation Management, customer support and Quality of Service The technology on which the present invention is based is a formula driven language that translates Service Level Agreement details into commands As such these details can be tracked and processed to produce detailed reports and summaries

Service level management using QoS monitoring, diagnostics, and adaptation for networked enterprise systems

Abstract: As enterprise services increasingly interconnect as networked services in a service-oriented architecture (SOA), service level management (SLM) is becoming a complex problem and can no longer be handled by traditional monitoring tools like Microsoft SMS. SLM is a process managing the quality of services demanded by clients and offered by providers. This paper presents two contributions to the research of SLM. First, instead of considering monitoring as an isolated service, it incorporates monitoring as an integral part of a comprehensive QoS management framework. This framework consists of QoS management concepts and services including service level contract management, admission control, resource management, monitoring, diagnostics, and adaptation. Using this framework, clients are able to negotiate quality of service contracts with providers and providers are able to optimize system resources to meet contract requirements. The second contribution is the incorporation of diagnostic service in the QoS management framework. Based on data feed from monitoring service, diagnostic service is able to detect any condition changes and to reason about the causes of any degradation conditions in the networked enterprise system. With condition detection and situation understanding, QoS management can then proactively activate adaptation mechanisms to maximize the system's ability to meet QoS contract requirements of concurrent clients. Our monitoring service uses both reporting approach and probing approach to acquire the information of the health status of elements of a networked system. The monitored data is then fed to our diagnostic service to reason about root causes of anomalies, using graphical models. Depending on the system health status and root causes, appropriate adaptations are triggered proactively to improve the system performance under the constraints of concurrent QoS contracts. We validate our SLM approach using QoS management services integrated in a publish/subscribe style of SOA. We then demonstrate via experiments some benefits of QoS monitoring, diagnostics, and adaptation services for responsiveness SLM.

Cost analysis issues in a wireless multihop architecture with fixed relays

Abstract: The infrastructure costs of a hybrid cellular-multihop and a traditional single-hop cellular system are compared in this paper with the help of a linear cost model. The cost is evaluated in a greenfield operator scenario most suited in a suburban type of environment, by defining a desired service level as achieved bit-rate per area unit [kbps/km/sup 2/]. The hybrid system consists of macro base stations and fixed wireless routers. The impact of the radio resource allocation scheme on the cost is exemplified with schemes: a cell-based TDMA scheme and a centralized STDMA scheme. Numerical results show that the hybrid system outperforms the traditional one in terms of infrastructure cost if the STDMA scheme is used and if the cost of a relay is 3 to 7% of the macro base station cost, depending on the desired service level.

A cost/benefit model for investments in inventory and preventive maintenance in an imperfect production system

Abstract: In this research, a cost/benefit model is developed for supporting investment strategies about inventory and preventive maintenance in an imperfect production system The effect of such investments on the return is expressed as a function of measurable variables Using this model, the decision maker can decide whether investments in inventory and preventive maintenance are necessary and how much to invest This investment model is developed for an imperfect production system with imperfect product quality and supplied quantity Investments in inventory and preventive maintenance increase service level for the customer and reduce the proportion of defective products, and hence affect stockout and backlog of supplied products and the delivery time to the customer This model includes in its scope investment in inventory and preventive maintenance, manufacturing cost, inventory cost, backlog cost, stockout cost, and delay cost This model can be used to evaluate the effects of investments on the financial cost/benefit and other relevant critical performance measures This model can be solved by an iterative process using the Sequential Quadratic Programming Method The optimal investment in inventory with respect to the service level and the optimal investment in preventive maintenance with respect to the proportion of defective items can be obtained first, and then other relevant costs can also be obtained

Simultaneous usage of agent and service parameters

Abstract: A system and method for routing a contact to an agent based on a combination of agent parameters and service parameters includes receiving a first contact and determining attributes of the contact. A multi-dimensional agent-service matrix is generated wherein each cell includes at least an agent/service value corresponding to at least a combination of agent and service parameters. The agent parameters may include agent skill level, agent idle time, and order of agents receiving a contact. The service parameters may include wait time of contact in queue, service level goal, number of contacts in queue, and service affinity. A first available agent is identified from the agent-service matrix having a maximum agent/service value and the contact is routed to that agent. Every available agent in the agent-service matrix is available to handle the contact.

Reputation-based pricing of P2P services

Abstract: In the future peer-to-peer service oriented computing systems, maintaining a cooperative equilibrium is a non-trivial task. In the absence of Trusted Third Parties (TTP's) or verification authorities, rational service providers minimize their costs by providing ever degrading service quality levels. Anticipating this, rational clients are willing to pay only the minimum amounts (often zero) which leads to the collapse of the market.In this paper, we show how a simple reputation mechanism can be used to overcome this moral hazard problem. The mechanism does not act by social exclusion (i.e. exclude providers that cheat) but rather by allowing flexible service level agreements in which quality can be traded for the price. We show that such a mechanism can drive service providers of different types to exert the social efficient effort levels.