Search results for "resource"
showing 10 items of 4058 documents
Performance evaluation of differentiated access mechanisms effectiveness in 802.11 networks
2005
The IEEE 802.11e draft specification aims to extend the original 802.11 MAC protocol by introducing priority mechanisms able to manage bandwidth and resource allocation according to the QoS needs of real-time applications. Different strategies based on MAC parameter diversifications, such as contention window limits, contention window updating factor and silence monitoring time, can be pursued in order to provide service differentiation, also in the case of distributed access. In this paper, we investigate on the behaviour of each differentiation possibility under different load conditions and traffic requirements. Our results show that the most powerful mechanisms which provide service dif…
Mobile agents and grid computing
2004
Publisher Summary This chapter describes mobile agents as an effective solution for grid service provision. A short overview is first introduced on the grid paradigm and the most known research activities in the field. Then, mobile agents are discussed and a comparison with the remote procedure call (RPC) method is made as far as the most effective solution to minimize network overload and fault occurrences is concerned. The common feature of all grid architectures is a coordinated and controlled resource sharing between the members of a dynamic multi-institutional virtual community. Community members agree on a set of sharing rules and permissions, by which resources to be shared and membe…
An Approach to Cadastral Map Quality Evaluation in the Republic of Latvia
2009
An approach to cadastral map quality evaluation is proposed, which is elaborated and implemented by State Land Service of the Republic of Latvia. The approach is based on opinion of Land Service experts about cadastral map quality that depends on its usage points. Quality parameters of cadastral map objects identified by experts and its limit values are used for evaluation. The assessment matrix is used, which allow to define cadastral map quality that depends on its usage purpose. The matrix is used to find out, of what quality a cadastral map should be in order to be used for the chosen purpose. The given approach is flexible, it gives a possibility to change sets of quality parameters an…
Assessing the quality of service to customers provided by water utilities: A synthetic index approach
2017
Abstract Currently, water and sewer companies face the challenge of improving their quality of service to customers (QSC). Performance indicators are essential to monitor and benchmark the QSC of water companies; however, individual indicators do not provide a holistic evaluation of the quality of water and sewer services provided to customers. This study proposes an innovative QSC index based on distance-function techniques that makes it possible to compare changes in the QSC of water companies among locations and temporal periods. A case study assesses changes in QSC for a sample of Chilean water and sewer companies from 2007 to 2014. The results show that in spite of the efforts made by …
The role of organizational facilitators in promoting job-related mental health and group service effectiveness: a two-wave analysis
2016
This study aimed to add to knowledge by providing a more systematic integration of work characteristics, workers’ health and performance. The two-wave multi-source study was conducted to test the relationship over time between the healthy states of groups of service-oriented workers and their service effectiveness when their organizations provide facilitators such as training, technical support and autonomy. The study takes healthy states to be a composite of affective-motivational and competent collective states (collective vigour and service competence) and service effectiveness. Service effectiveness was a combination of service quality as assessed by customers and their loyalty intentio…
Analysis and Simulation of the Signaling Protocols for the DiffServ Framework
2006
This paper considers signaling protocols for the DiffServ QoS framework. Originally, DiffServ had no standardized signaling solution, which resulted in the static configuration for the DiffServ domain. However, the dynamic allocation of resources within the domain allows to ensure the per-flow QoS guarantees and achieve better performance. At the moment, several signaling solutions for DiffServ framework are available. Thus, it is crucial to analyse these solutions and interconnections between them. In particular, the RSVP, aggregated RSVP, GIST, COPS, and SIP protocols will be considered. The simulation comprises several scenarios that present that the dynamic allocation of resource within…
A Hierarchy of Twofold Resource Allocation Automata Supporting Optimal Sampling
2009
We consider the problem of allocating limited sampling resources in a "real-time" manner with the purpose of estimating multiple binomial proportions. More specifically, the user is presented with `n ' sets of data points, S 1 , S 2 , ..., S n , where the set S i has N i points drawn from two classes {*** 1 , *** 2 }. A random sample in set S i belongs to *** 1 with probability u i and to *** 2 with probability 1 *** u i , with {u i }. i = 1, 2, ...n , being the quantities to be learnt. The problem is both interesting and non-trivial because while both n and each N i are large, the number of samples that can be drawn is bounded by a constant, c . We solve the problem by first modelling it a…
The simulation and analysis of the revenue critierion based adaptive WFQ
2003
This paper presents the simulation and analysis of the adaptive resource allocation model, which was proposed and theoretically considered in our previous works. It relies upon the Weighted Fair Queueing (WFQ) service policy and uses the revenue criterion to adjust weights. The purpose of the proposed model is to maximize a provider's revenue and, at the same time, ensure the required Quality-of-Service (QoS) for end-users. Our previous works provided the theoretical evaluation of the proposed model and considered the single-node case only. This paper presents more realistic network scenario, which includes a set of clients and several intermediate switching nodes with the proposed model. T…
Mobile agents, globus and resource discovery
2004
Publisher Summary This chapter discusses grid technology and some related problem. The overview of grids, in terms of application fields and needed protocols is given. The common feature of all grid architectures is a coordinated and controlled resource sharing between the members of a dynamic multi-institutional virtual community. The members of such a community agree on which resources will be shared and which members of the community will be enabled to access these resources, thus defining a set of sharing rules and permissions. The Globus project is discussed, which is nowadays the de facto standard for grid environments, with emphasis on its resource discovery components. Finally, the …
Detection of Anomalous HTTP Requests Based on Advanced N-gram Model and Clustering Techniques
2013
Nowadays HTTP servers and applications are some of the most popular targets for network attacks. In this research, we consider an algorithm for HTTP intrusions detection based on simple clustering algorithms and advanced processing of HTTP requests which allows the analysis of all queries at once and does not separate them by resource. The method proposed allows detection of HTTP intrusions in case of continuously updated web-applications and does not require a set of HTTP requests free of attacks to build the normal user behaviour model. The algorithm is tested using logs acquired from a large real-life web service and, as a result, all attacks from these logs are detected, while the numbe…