Constructing Optimal 2D Variable-Weight OOCs from Semicyclic Group Divisible Designs

Today, many have attempted to provide multimedia services using IP over Satellite broadband infrastructure. The traffic complexity and real-time constraints of the multimedia services pose challenges to guarantee the delivery of packets end-to-end. At present, Quality of Service (QoS) in the router’s forwarding plane provides traffic differentiation capability in the traditional terrestrial networks. Traditional networking systems that implement QoS have packet classification and dropping mechanisms in the network edge and strong shapers and schedulers in the network core. In this paper, we clearly show that adapting the traditional QoS techniques to satellite medium will not optimize multimedia and other real-time broadband services. We also propose a new QoS architecture that provides a mechanism to optimize multimedia services over expanded broadband offering. In addition, we clearly establish in this paper using simulation results, that the proposed architecture is necessary to provide service guarantees for multimedia traffic over expanded broadband satellite networks. The results provided in the paper demonstrate that the proposed architecture has lower delay and jitter and higher packet delivery ratio compared to no QoS or partial QoS implementations.

In cloud computing, there exist several classes of web services, and each class of web service contains multiple services which have different Quality of Service (QoS) values. To provide QoS for users, determining the best service composition that meet user's preferences is necessity. Finding the best service composition needs a certain method in order to provide the best combination of QoS with minimum response time, while in some cases, the process is bounded by budget constraint provided in user's preferences. In a simple method, for selecting the best service composition, we need to evaluate nm combinations of n classes of service and m services member. This condition leads to a large computing costs and memory consumption that occur during the process of generating the combination of data. To reduce the number of combinations, we propose an approach for finding the best service composition of web services using skyline algorithm which can adapt different user preferences of QoS. While selecting the best composition, we also take consideration in budget as constraint by selecting the closest user's budget with the best skyline result of services. SalSa skyline algorithm have given the new alternative ways to finding the best candidates of services in each class of service in reasonable time. These happened because we only need to evaluate the smaller parts of members in each class which will need much time if the number of services is plenty. Moreover, we also presented a method to find the best composition of services which able to present the composition that meet the user's budget.

There has been active research on quality of service (QoS) multicasting. Very few, however, addresses QoS inter-domain multicasting. We present a QoS extension to BGMP (border gateway multicast protocol) which, proposed by Kumar, et al., is currently one of the most promising inter-domain multicasting proposals. With limited modification to the current BGMP, we extend it to support the so called two-bit differentiated service (including the classes of premium, assured, and best-effort services) proposed by Nichols, Jacobson, and Zhang. Detailed mechanisms of the QoS extension are described. Performance is evaluated through extensive simulation of real-network scenarios, supporting CBR, VBR, and best-effort traffic flows with the three classes of services. We believe that the work presented here is significant to the advancement of the next-generation Internet supporting QoS communications.

There is no network traffic classification in intermediate nodes in IEEE802.11e multi-hop wireless network, which results in delays for the traffic with higher levels of service. Also, there is no mechanism to support fairness in a shared environment with different classes of service, which leads to inappropriate quality of service. Previous studies were focused on improving network throughput and also the fairness among the traffic that belongs to one class of service and there is no solution for providing fairness among different classes of service in each individual node. In this paper, a new method is proposed for scheduling the traffic in each intermediate node which is based on Transmission Opportunity (TXOP). The new method ensures differentiated quality of service for service classes as well as improvement of throughput and end to end delay. Using dynamic TXOP along with the proposed method can provide desired quality of service as well as fairness in the bandwidth shared between different classes of services. Simulation results illustrate network throughput and end to end delay improvement for each class of service, in the case of using the proposed method, as well as fairness in using the shared bandwidth which leads to more efficient use of network resources.

Mobile broadband technologies are now an important part of the communication infrastructure even for most of the developing world. These technologies can potentially play an important role in improving the socioeconomic status of rural areas. However, adaptation of these technologies for provision of relevant multimedia services faces major challenges. Perhaps, Quality of Service (QoS) issues still tops the list of such challenges. In this work we study how to evaluate the QoS of cellular-based systems focusing on an application perspective. We quantify the QoS levels for different traffic models using application and network related parameters to identify the most suitable configuration for running multimedia-based services. More specifically, our analysis is based on considering a unified measure combining key QoS metrics such as packet loss, and delay. For evaluation purposes, we also investigate the QoS issues of deploying a distance education platform running over UMTS cellular systems. The QoS issues related to the deployment of multimedia services in cellular technologies are then considered and analyzed in detail through simulation studies. The results show that by inclusion of the communication technology and application related parameters along with the number of users in QoS evaluations, better performing network configurations can be readily selected. This is achieved, through our proposed application-based QoS evaluation scheme that is based on combining various related measures. The proposed scheme is shown to be particularly beneficial for evaluating and improving QoS for multimedia-based heterogeneous networks.

This paper addresses the issue of provisioning end-to-end quality of service (QoS) for multimedia services over heterogeneous networks and introduces a parametric model by using network calculus theory for QoS class mapping between different QoS domains. Then, a QoS mapping scheme based on flow aggregation (QMS-FAG) is proposed in this paper to mitigate the information loss problem due to mapping between QoS domains with different granularity of QoS class and to provide efficient network resources utilization by considering user's quality of experience. In QMS-FAG, the QoS requirements of service flows are indicated by a unique FAG identifier, which is described in a service flow map of QoS parameters. With FAG identifier and mapping executors sitting at the border of different QoS domains, QMS-FAG allows smooth QoS class mapping between networks with different granularity of QoS class. Both numerical analysis and simulation studies are given to demonstrate the efficiency of the proposed method.

Problem statement: The demand for multimedia applications in WiMAX networks is growing at a rapid pace. A method for guaranteeing Quality of Service (QoS) for different classes of traffic is therefore gaining importance. Hence desi gning and analyzing multimedia traffic and QoS parameters has become central to this problem. In t his study, we propose a cross layer frame work in which a coordination between the Medium Access Control layer (MAC) and the Physical layer (PHY) is established for guaranteeing the QoS requirement in a multiclass traffic WiMAX environment. Two traffic classes' real time Polling Service (rtPS) a nd non real time Polling Service (nrtPS) are considered for analyzing the performance. Approach: The objective of study is to guarantee QoS for multiple service class traffic in a multiple connec tion environment in WiMAX network. A cross layer design approach is used for this purpose. A priorit y scheduler at the MAC layer schedules the traffic based on channel state information. The Adaptive modulation and coding scheme is used at the physical layer that adapts to the scheduled traffic to stabilize the QoS requirements of different tra ffic classes. Results: The Priority value is estimated using the Friis eq uation that calculates the received power and determines the SNR. The average throughput, average bytes received and the packet loss are plotted against time. This indicated that these QoS parameters are stable over a period of time. Conclusion: A cross layer frame work was developed based on a scheduler for QoS stability that uses CSI at the MAC layer and an AMC at the PHY layer in WiMax Networks. The scheduler enjoyed flexibility and scalability, whose performance was evaluated against existing systems through simulati on.

A generic architecture for management and control of end-to-end quality of service over multiple domains

To analyze network QoS (Quality of Service) performance and better utilize network resources, this paper develops an analytical model of QoS class mapping for hybrid QoS domains based on network calculus theory. Based on this model, an elastic QoS Mapping scheme with Flow Aggregate (EQM-FA) is proposed to support end-to-end QoS of multimedia services over heterogeneous wireless networks. In EQM-FA, the QoS requirements of service flows are indicated by a unique flow aggregate identifier which can be described by the information describing QoS on a service flow map which is a multidimensional space of relevant QoS parameters. With flow aggregate identifier and mapping executors sitting at the border of different QoS domains, EQM-FA allows smooth QoS class mapping between different networks with different granularity of QoS class. Both numerical analysis and simulation studies are given to demonstrate the efficacy of the proposed method.

The traditional ant routing protocol provides an efficient way for dynamic routing in continuously changing networks. Due to their social behaviour, ants tend to find optimized paths based on network status information such as the path length and capacity. However, the conventional ant routing protocol tends to satisfy acceptable Quality of Service (QoS) requirements for the whole network traffic. The major problem is that different traffic types request different QoS requirements, and the traditional ant routing lacks the ability of providing different levels of QoS parameters for these different traffic types. In this paper, a novel technology is proposed to satisfy the requirements of different traffic types which vary in terms of bandwidth, latency and security. Oyster Optics Technology has been used to introduce the security as a new significant QoS factor.

Certain services may be provided in a continuous, one-dimensional, ordered range of different qualities and a customer requiring a service of quality q can only be offered a quality superior or equal to q. Only a discrete set of different qualities will be offered, and a service provider will provide the same service (of fixed quality b) to all customers requesting qualities of service inferior or equal to b. Assuming all services (of quality b) are priced identically, a monopolist will choose the qualities of service and the prices that maximize profit but, under perfect competition, a service provider will choose the (inferior) quality of service that can be priced at the lowest price. Assuming significant economies of scale, two fundamentally different regimes are possible: either a number of different classes of service are offered (DC regime), or a unique class of service offers an unbounded quality of service (UC regime). The DC regime appears in one of two sub-regimes: one, BDC, in which a finite number of classes is offered, the qualities of service offered are bounded and requests for high-quality services are not met, or UDC in which an infinite number of classes of service are offered and every request is met. The types of the demand curve and of the economies of scale, and not the pace of technological change, determine the regime and the class boundaries. The price structure in the DC regime obeys very general laws.

There have been research works on supporting QoS (Quality of Service) in a distributed multimedia systems. These researches can be categorized as following; system platform, real-time operating system, transport protocol, communication architecture. In distributed multimedia environment, QoS must be guaranteed in end systems, but much less progress has been made in addressing this problem. As the processing power of end systems increases, most of the bottleneck occurs in communication protocol, especially transport protocol. To meet an end-to-end QoS, overall QoS architectures must be integrated. In this paper, we propose a new QoS architecture and control mechanisms (group control, and flow control) to guarantee an end-to-end QoS for distributed multimedia services. We also verify proposed architecture by applying them to a multimedia conferencing system in LAN.

SUMMARYWireless mesh networks (WMNs) as community‐ and city‐wide type networks are required to extend their capability to offer real‐time multimedia services. While technologies exist to support quality of service (QoS) at node level, we propose here a network‐wide multi‐step solution to manage and offer QoS across a WMN. From a provider perspective, the provisioning and fulfillment of QoS‐based services fall under the realms of service management, network and traffic engineering functions. We describe the relevant functions required to design, implement and operate a WMN for providing a qualitative QoS to end‐users. Our proposed solution considers network planning aspects, including node placement, node clustering and frequency assignments, route discovery between ingress–egress points and appropriate QoS provisioning across the network. Route‐level QoS provisioning is defined as the process of allocating resources to the nodes along the identified routes to meet a priori known aggregated traffic demands in order to satisfy the QoS requirements for different types of application. Simulation and experimental tests are conducted to validate the correct behavior of processes/algorithms and to access the solution in achieving QoS for aggregate user traffic. Copyright © 2012 John Wiley & Sons, Ltd.

This chapter describes the support for IP based multimedia services on Third Generation (3G) wireless cellular networks. While earlier cellular networks offered only basic IP connectivity on a best-effort basis, 3G networks provide explicit support for real time multimedia services with guaranteed Quality of Service (QoS). As a result, they can offer traditional voice telephony, rich telephony services and multimedia streaming over IP, both inside a 3G network and in conjunction with external networks such as the Internet, the Public Switched Telephone Network (PSTN) and the Integrated Services Digital Network (ISDN). In fact, 3G networks will deploy for the first time in a large scale technologies such as IP version 6 (IPv6) and policy based IP QoS, spearheading the introduction of such technologies into the Internet. The two most important aspects of 3G networks with respect to IP based multimedia services are the IP Multimedia Subsystem (IMS) and the Multimedia Broadcast / Multicast Service (MBMS). The IMS enables complex IP based multimedia sessions to be created with guaranteed QoS for each media component. Example applications include voice telephony and video conferencing. The IMS interoperates with both traditional telephony services and external IP based multimedia services. The MBMS provides native IP broadcast and multicast support in 3G networks, allowing high bandwidth services to be economically offered to multiple users. Example applications include video streaming via multicast and location based services via broadcast. The MBMS interoperates directly with IP multicasting. While both the IMS and the MBMS are IP based, their standardization is proceeding independently. It is however clear that their combination would allow numerous new services to be provided. The outline of this chapter is as follows. In Section II we give an overview of cellular networks and their evolution, while in Section III we describe in detail a specific 3G network, the Universal Mobile Telecommunications System (UMTS). Section IV presents an introductory description of the features and services provided by the IMS and the MBMS. In Section V we provide the details of the IMS, including service architecture, session setup and control and interworking issues. Section VI describes the MBMS in the same manner as for the IMS. Finally, Section VII discusses the QoS issues for IP based multimedia services, describing the overall QoS concept, the policy based QoS control scheme and its application to IMS sessions. At the end of the chapter, Tables II and III list the acronyms used. An extensive UMTS vocabulary is provided in [1].

In last few years there has been significant growth in the area of wireless communication. Quality of Service (QoS) has become an important consideration for supporting variety of applications that utilize the network resources. These applications include voice over IP, multimedia services, like, video streaming, video conferencing etc. IEEE 802.16/WiMAX is a new network which is designed with quality of service in mind. This paper focuses on analysis of quality of service as implemented by the WiMAX networks. First, it presents the details of the quality of service architecture in WiMAX network. In the analysis, a WiMAX module developed based on popular network simulator ns-2, is used. Various real life scenarios like voice call, video streaming are setup in the simulation environment. Parameters that indicate quality of service, such as, throughput, packet loss, average jitter and average delay, are analyzed for different types of service flows as defined in WiMAX. Results indicate that better quality of service is achieved by using service flows designed for specific applications.