The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
Clouds offer great flexibility for scaling applications due to the wide spectrum of resources with different cost-performance, inherent resource elasticity and pay-peruse charging. However, determining cost-time-efficient cloud configurations to execute a given application in the large resource configuration space remains a key challenge. The growing importance of elastic applications for which the...
The Information-Centric Network (ICN) is very promising in the area of Complex Active Networks (CANs), where the data-centric approach is useful in reducing the data retrieval latency as well as the network traffic of active networking services. Also, the in-network caching and processing capabilities in ICN limits the massive data access to the data producers and so relaxes the need of continuous...
Ubiquitous in-network caching is one of the important aspects of the Information-Centric Networking (ICN), which has been a hot topic of ICN research. Many works have tried to propose better caching schemes to solve the drawbacks of the default en-route scheme, but most of them are insufficient to improve performance of entire network for just considering single layer optimization factor. Also considering...
The paper deals with the contact center modeling with emphasis on the optimal number of agents. The contact center belongs to the queueing systems and its mathematical model can be described by various important parameters. The Erlang C formula tends to be suitable tool for the modeling of QoS parameters of contact centers. In our paper, we propose two parameters: downtime and administrative task...
The performance of modern data-intensive applications is closely related to the speed of data access. However, a physical database optimization by design is often infeasible, due to the presence of large databases and time-varying workloads. In this paper we introduce a novel methodology for physical database optimization which allows for a quick and dynamic selection of indexes through the analysis...
Hybrid Clouds couple the scalability of public Clouds with the greater control supplied by private ones. Hybrid Cloud Brokers support customers in selecting the most suitable providers' offers, optionally adding the provisioning of dedicated services with higher Quality of Service (QoS) levels. A clear evaluation of the benefits on performance and energy savings brought about by any allocation strategy...
Although cloud computing greatly utilises virtualised environments for applications to be executed efficiently in low-cost hosting, it has turned energy wasting and overconsumption issues into major concerns. Cloud infrastructure is built on a great amount of server equipment, including high performance computing (HPC), and the servers are naturally prone to failures.In this paper, we report on an...
The dramatically increasing energy consumption of data centers is an important issue and one of the most efficient ways to tackle the issue is through server consolidation. The basic idea of server consolidation is to move all virtual machines (VMs) to as few energy efficient servers as possible, and then switch off unused servers. Many efficient server consolidation approaches have been proposed...
Multi-Tenant Data Center (MTDC) operators can increase their profits by oversubscribing their power infrastructure. However, without an appropriate power control mechanism, oversubscription can lead to expensive unplanned service outages. We propose a new power control mechanism, LOCAP (LOCAl Price for power), as a means of 1) incentivizing tenants to reduce power use to save energy and 2) controlling...
Energy consumption has become a key issue for running large-scale data center networks (DCN) nowadays. Previous studies mainly focus on energy saving through reducing the number of active servers or network switches with traffic consolidation. However, since this mechanism benefits from the routing flexibility, both the gained energy savings and flow performance are limited by the conventional static...
The finite input source queueing system has been widely used to solve many problems appearing on machine maintenance and repair systems, client-server computing, and production line operations, etc. In classical queueing models, arrival intensity is assumed to be a poisson distribution and the service times of all servers follow a independent and identically exponential distribution, in which the...
It is well known that load balancing and low delivery communication cost are two critical issues in mapping requests to servers in Content Delivery Networks (CDNs). However, the trade-off between these two performance metrics has not been yet quantitatively investigated in designing efficient request mapping schemes. In this work, we formalize this trade-off through a stochastic optimization problem...
As cloud computing industry adoption rate is increasing, service cost management and optimization are becoming one of the most important issues from the perspective of cloud users. This paper is looking into possibility of using information about application type and its resource usage profile in the process of identifying optimized service placement in cloud environments. Such placement should result...
Software applications contain valuable assets that, if compromised, can make the security of users at stake and cause huge monetary losses for software developers. Software protections are applied whenever assets' security is at risk as they delay successful attacks. Unfortunately, protections might have recognizable fingerprints that can expose the location of the assets, thus facilitating the attackers'...
In this paper, we investigate the service capacity of a software-defined network with network function virtualization and service chaining. To obtain and achieve the service capacity, we formulate a mixed integer linear programming problem to jointly optimize the placement of virtual machines and the steering of network flows. In addition, we propose the greedy linear programming relaxation algorithm...
With the NFV paradigm, network services are usually instantiated in datacenters (e.g., as VMs), while softwaredefined networks provide just plain connectivity. However, common SDN controllers can do much more than just traffic steering; particularly they can execute network applications such as NAT, DHCP, and more. This paper presents a software architecture that can advertise an SDN domain as having...
Due to the advantages of cloud computing, it has been adopted as deployment platform of SBS (Service-based Systems). It also provides an elastic "pay-as-you-go" mode, which creates new resource allocation challenge that satisfying the QoS (Quality of Service) requirements with least resource allocation. There has been much interest in using feedback control to make resource allocation, but...
The paper proposes provisioning methods for VoD service providers offering adaptive video streaming in a cloud environment. Our methods minimize costs paid by VoD provider thanks to rational use of on the fly video transcoding service which eliminates storage cost of rarely requested video profiles. In the paper, we formulate provisioning problem, propose optimization and heuristic methods that determine...
The problem of efficient resource management in large cloud data centres is well recognised in the cloud management community. With the rising demand for cloud services and expansion of the size and distribution of data centres, the repercussions of not taking into account all parameters of interest while allocating resources are becoming significant. Hence, one of the major issues today is how to...
The main goal of this paper is to manage the switching on/off of servers in a data center during time to adapt the system with incoming traffic changes to ensure a good performance and a reasonable energy consumption. In this work, the system is modeled by a queue then, an optimization algorithm is designed to manage energy consumption and quality of service in the data center. For several systems,...
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.