Flexible QoS Support in DVB-RCS2

Postprin

Resource allocation and scheduling of multiple composite web services in cloud computing using cooperative coevolution genetic algorithm

In cloud computing, resource allocation and scheduling of multiple composite web services is an important and challenging problem. This is especially so in a hybrid cloud where there may be some low-cost resources available from private clouds and some high-cost resources from public clouds. Meeting this challenge involves two classical computational problems: one is assigning resources to each of the tasks in the composite web services; the other is scheduling the allocated resources when each resource may be used by multiple tasks at different points of time. In addition, Quality-of-Service (QoS) issues, such as execution time and running costs, must be considered in the resource allocation and scheduling problem. Here we present a Cooperative Coevolutionary Genetic Algorithm (CCGA) to solve the deadline-constrained resource allocation and scheduling problem for multiple composite web services. Experimental results show that our CCGA is both efficient and scalable

Model Based Development of Quality-Aware Software Services

Modelling languages and development frameworks give support for functional and structural description of software architectures. But quality-aware applications require languages which allow expressing QoS as a first-class concept during architecture design and service composition, and to extend existing tools and infrastructures adding support for modelling, evaluating, managing and monitoring QoS aspects. In addition to its functional behaviour and internal structure, the developer of each service must consider the fulfilment of its quality requirements. If the service is flexible, the output quality depends both on input quality and available resources (e.g., amounts of CPU execution time and memory). From the software engineering point of view, modelling of quality-aware requirements and architectures require modelling support for the description of quality concepts, support for the analysis of quality properties (e.g. model checking and consistencies of quality constraints, assembly of quality), tool support for the transition from quality requirements to quality-aware architectures, and from quality-aware architecture to service run-time infrastructures. Quality management in run-time service infrastructures must give support for handling quality concepts dynamically. QoS-aware modeling frameworks and QoS-aware runtime management infrastructures require a common evolution to get their integration

Technological Issues: Closing the Digital Divide Through Resource Allocation Techniques

It is only after access to technology is assured that computer literacy can begin. Access is not simply having access to up-to-date technology; it should also include access to qualified teachers, appropriate software and Web content. Vital to this issue is the quality and quantity of the access. The optimisation of the bandwidth use, obtained by implementing bandwidth allocation schemes and suited protocol solutions, will allow providing improved quality of service and reduced cost of broadband Internet access. This technology will allow the provision of QoS-based broadband services in hazardous environments and in areas where the technological development is less spread and the Internet isn\u27t well delivered. Resource allocation has become the most important technology in satellite and wireless networks. All satellite systems are limited by bandwidth and power, which are both expensive resources. Operators of satellite systems receive fixed allocations of these resources and as a result, are limited in the number of users they can support on one system. To combat this problem and to lower the costs for system operators, certain power and bandwidth conservation methods have been developed. In the past, satellite systems were used to deliver telephony or transaction-based applications. Since telephony is a single application with a predefined bandwidth requirement, a simple resource allocation technique such as Demand Assigned Multiple Access (DAMA) is sufficient. A transaction-based application requires a simple ALOHA channel. The development of Two-Way IP access systems, which support a variety of protocols and applications, has created the need for more complex resource allocation algorithms. Faced with a combination of real-time applications, such as Voice over IP, and non real-time applications that still require high bandwidth, such as e-mail transmission, resource allocation algorithms have had to work with two conflicting issues: Quality of Service and bandwidth consumption. As a result, Bandwidth On Demand (BOD) algorithms were developed to manage resource allocation and Quality of Service mechanisms were developed to identify the needs of different applications. This paper discusses the application of different resource allocation algorithms to different type of traffic. Using mathematical formulation it presents the bandwidth saving achieved by BOD for IP type of traffic