On QoS-aware publish-subscribe

A service level agreement (SLA) is part of a contract between a cloud service provider (CSP) and a cloud service user (CSU) which defines and describes different agreed properties of the service. The negotiation of the SLA between a CSU and a CSP is a pivotal process in the SLA life cycle. An SLA may include many negotiable quality of service (QoS) parameters with each QoS parameter having multiple acceptable values. Different combinations of acceptable values for all QoS parameters grow exponentially as number of QoS parameters and their selectable values increase. Manually negotiating for all of the QoS parameters considering their various options can be an erroneous and diligent task with lower utility. In this paper, a time efficient flip-flop negotiation strategy for the SLAs in cloud services is presented. The flip-flop negotiation strategy is based on a time dependent 3D utility function and on a dynamic concession strategy using the polynomial extrapolation of opponent's concession. This negotiation strategy is useful for time-critical cloud services as it operates with a motive of reaching an agreement at earlier time without compromising over the utility level of the agreement. Moreover, a multi-provider concurrent negotiation method is presented in this work using the flip-flop negotiation strategy. Multiple experiments are performed (using the implementation of flip-flop negotiation strategy) to test the presented work. The results of the experiments enforce the validity of the flip-flop negotiation strategy for such cloud services where time is an important factor during the SLA negotiation process.

For multimedia applications, the routing algorithms should consider many Quality of Service (QoS) parameters. However, to find routes with two or more QoS parameters is an NP-hard problem. Therefore, recently many researchers are trying to use heuristic methods such as Genetic Algorithm (GA). In a previous work, a QoS multicast routing based on GA was proposed. However, in this algorithm, the multicast routing falls in the local minimum and cannot satisfy the application requirements. In this paper, we propose a new QoS multicast routing protocol, which has better genetic operations than the conventional algorithm, resulting in a better performance.

Now we are in the era of ubiquitous computing. Internet of things (IoT) is getting matured in various parts of the world. In coming few years' billions and trillions of things will be connected to the internet. To deal with these huge number of devices in a network we need to consider Quality of Service (QoS)parameters so that system operations can be performed in a smoother way. Mathematical modelling of these QoS parameters gives an idea about which factors are needs to consider while designing any IoT-enabled system at the same time it will give the performance analysis of the system before implementation. In this paper comprehensive literature survey is done to discuss various issues related to QoS and gap analysis is also done for IoT Enabled systems. This paper proposes general steps to build a mathematical model for a system. It also proposes the mathematical model for QoS parameters like reliability, communication complexities, latency and aggregation of data for IoT. To support proposed mathematical model proof of concept also given.

Multicast routing is an effective way to communicate among multiple hosts in a network. For multimedia applications, the routing algorithms should consider many Quality of Service (QoS) parameters such as delay, cost and so on to find a new route. However, to find routes with two or more QoS parameters is an NP-hard problem. This paper describes a new evolutionary scheme for optimization of multicast QoS routing based on the hybrid of Genetic Algorithm (GA) and Particle Swarm Optimization (PSO), called HGAPSO. In HGAPSO, individuals in a new generation are created, not only by crossover and mutation operation as in GA, but also by PSO. The upper-half of the best-performing individuals in a population are regarded as elites. Instead of being reproduced directly to the next generation, these elites are first enhanced. The group constituted by the elites is regarded as a swarm, and each elite corresponds to a particle within it. In this regard, the elites are enhanced by PSO, an operation which mimics the maturing phenomenon in nature. This scheme can simultaneously optimize the cost of the tree, the maximum end-to-end delay, the average delay and the maximum link utilization. In this way, a set of optimal solutions, known as Pareto set, is calculated in only one run, without a priori restrictions. It has revealed an efficient method of the reconstruction of multicast tree topology and the experimental results demonstrated better performance than the conventional GA optimization method.

This paper evaluates inter-satellite communication for a low earth orbit CubeSat network. This paper consists of two parts: determination and estimation of quality of service (QoS) parameters and evaluation of the feasibility of a Massive Multiple Input Multiple Output (MIMO) system for inter-satellite links. CubeSats are low-cost and small satellites that were initially designed by students during the educational process but are now launched for conducting space research and for commercial use. Recently, some companies and research studies promoted CubeSats to build a wireless communication networks for different proposes, such as earth observation, weather forecasting, providing access to the internet, internet of things and machine to machine services. The main distinguishing features of a CubeSat network include low-cost and fast deployment with a consequent advantage: the possibility to build a large network (hundreds of spacecraft) with limited resources. However, due to the limited size and function of CubeSats, the feasibility of a CubeSat network with inter-satellite links is debatable. In this paper, we investigate the QoS parameters for an inter-satellite link and factors affecting it. The theoretical design with a constructive drawing of massive MIMO has been made. The possibility and time duration of inter-satellite communication has been calculated for three different cases using real data and including Massive MIMO. The simulation of orbit movements for groups of CubeSats has been made. The correlation between relative positions of satellites in orbits, parameters of communication channels and the QoS was determined. The feasibility of massive MIMO for CubeSat communications has been estimated. Based on simulation results, suggestions and possible technical and non-technical solutions were highlighted together with future studies and simulations.

With the rapid growth of functionally identical web services, Quality of Service (QoS) plays vital role for deciding the most suitable services for consumers. Although, QoS for web services has gained extensive attention in the literature, most of the existing efforts are unable to consider the multiperspective QoS of web services. Unlike conventional software paradigms, web services are provided, developed and used by different users such as provider, consumer and broker. As a result, QoS requirements vary from user to user. Existing researches are unable to provide standard solution, which can deal with what service providers, consumers and broker should expose in service description as QoS parameters. Therefore, in this book chapter, a multiperspective PCB-QoS classification of non-functional parameters along with new QoS parameters, i.e. access rate and Overall Aggregated Effective Quality of Service (OAEQoS) is presented. Due to the extensible nature of PCB-QoS classification, it can be extended to accommodate more number of QoS parameters. This QoS classification is based on the idea of partitioning the generic QoS parameters according to multi-user’s perspective. An Average Real Value Sum Method (ARSM) based on default priority constraints is also proposed for ranking of web services that uses the presented QoS classification. With the help of proposed approach, the user can specify the service requirements without taking the hurdle of specifying the weights for each QoS parameter during web service operations. It also prevents the services from malicious service provider to publish the incorrect and inaccurate QoS information. Experimental evaluation shows the effectiveness of proposed approach over the existing approach.

This paper presents a comparative study of VoIP quality over 3G networks, based on Fair Usage Policy (FUP) and Access Unlimited Internet Service (AUIS) provided by two main 3G operators using Skype and a form of mobility usage, defined as semi-dynamic tests. The tests were conducted on electric train called BTS Skytrain (Sukhumvit line). After gathering data of degraded speech files from the tests with Thai speech files, they were processed using a tool called Perceptual Evaluation of Speech Quality tool (PESQ) to obtain the values of Mean Opinion Score (MOS), whereas, data of major Quality of Service (QoS) parameters, consisting of loss, delay and jitter were also gathered. Then, it has been analyzed and found that VoIP quality has been impacted by FUP because QoS parameters and MOS tend to be worse than the values from AUIS.

In this paper, we propose a new approach for video quality control for multimedia networks. Our new approach is based on video quality measure that combines both the network quality of service (QoS) as well as the user quality of experience (QoE). The proposed approach improves the end-to-end traditional video quality control for multimedia network by including the human perception of video data, which is major concern for the video client, along with the network quality of service (QoS) measurements. We will show that the proposed QoS-QoE based video quality control algorithm can reflect both the condition of the network environment and the human perception of the received networked video data stream. According to both QoS and QoE parameters, rather than using only QoS parameter, video quality control action will satisfy the user needs more than relying only on the network conditions. Since our proposed QoE parameter Self-Reference Complex Wavelet Video Structural Similarity Index (SRCW-VSSIM) can be obtained with no reference (NF) video data, it satisfies the requirement of real-time video transmission.

This thesis provides a detailed analysis of the effects of TCP and UDP traffic over a LAN and WAN medium. In addition, it also analyses some real time applications like audio, video and web browsing that is affected by TCP traffic while sharing a bottleneck node and/or link resources. As network industry is growing continuously, the network administrator should be aware of TCP and UDP traffic that is traversing through their network. The analysis and monitoring of the traffic is crucial as it directly affects the performance of the network. Finding a cause for the poor performance of the network is quite important because it gives an idea to troubleshoot and resolve the issues effectively. In this thesis, we have created topologies using Cisco’s Virtual Internet Routing Lab (VIRL) [7]. They replicate an organizational infrastructure with client-server environment in LAN and WAN. Routing protocols such as OSPF and BGP are used to mimic the real world internet. A built-in LXC-iperf tool is used to generate the TCP and UDP traffic. During the generation of the traffic, various parameters are changed or controlled to see their effect on the network performance. As a learning and informative research, this thesis considers several Quality of Service (QoS) parameters that characterize the performance of an overall network. In particular, this thesis obtains packet loss, throughput, and jitter as QoS parameters when the resource has both TCP and UDP traffics simultaneously. We have examined, the effects on (i) TCP throughput and packet loss and (ii) UPD packet loss and jitter of (a) real time audio, (b) video, and (c) web browsing applications. These parameters examine how the traffic be manipulated to keep minimum packet loss, minimum jitter and maximum throughput. It is needless to say that all are competing with each other (TCP/UDP traffic) for sharing bottleneck resources. We have used a sample time of 15 seconds for each of our experimental results presented in this thesis. Our analysis shows that the best performance of the real time video and audio application is obtained when we select large size packet but its size being less than MTU of the link (without reducing the data rates). Similarly, in case of web browsing, we notice that throughput increases by increasing the window size and decreasing the latency. Efficient outcomes with the traffic analysis are achieved only if the experiments are carried out with adequate amount of attention.

With the proliferation of service-oriented architectures (SOAs), a myriad of services are available to users. However, it is not pragmatic to employ trivial approaches for selecting a particular service from the available pool of services, particularly since employing a service implicitly entails subscribing to its benefits and shortcomings. This chapter presents a novel scheme for multi-criteria-based decision-making for service selection and composition. The proposed model is employed for selecting a localization service in a wireless sensor network (WSN). Localization of sensor nodes is an important phase of WSN deployment. Service selection and composition for localization are a challenging task, since the details of lower-level implementation-related information are not readily available to users. Additionally, runtime constraints are not very well understood, and even identification of quality of service (QoS) parameters for every given service is in itself a complex task. Therefore, this research work proposes a novel QoS-based flexible service selection and composition model that provides a platform for users to select the best possible service. A QoS-based taxonomy for the design goal, network, and application requirements is illustrated, and a mathematical formulation is presented using the analytical hierarchy process (AHP). The proposed framework is validated and tested based on given QoS parameters, and the results demonstrate the efficacy of the proposed method.

Background: QoS parameters are volatile in nature and possess high nonlinearity, thus making the IoT-based service and recommendation process challenging. Methods: An efficient and accurate forecasting model is lacking in this area and needs to be explored. Though an artificial neural network is a prominent option for capturing such nonlinearities, its efficiency is limited by the structural complexity and iterative learning method. The random vector functional link network (RVFLN) significantly reduces the time complexity by randomly assigning input weights and biases without further modification. Only output layer weights are calculated iteratively by gradient methods or non-iteratively by least square methods. It is an efficient algorithm with low time complexity and can handle complex domain problems without compromising accuracy. Motivated by these characteristics, this article develops an RVFLN-based model for forecasting QoS parameter sequences. Results: Two real-world IoT-enabled web service dataset series are used in developing and evaluating the effectiveness of RVFLN-based forecasts in terms of three performance metrics. Conclusion: Experimental results, comparative studies, and statistical tests are conducted to establish the superiority of the proposed approach over four other similar forecasting techniques.

Routing is an important process in computer networks, which involves selecting a path for packet data. The routing mechanism is governed by protocols at layer three of the OSI model or layer two of the TCP/IP model. Routing can be static or dynamic, with dynamic routing algorithms automatically determining the best path in the network. One commonly used dynamic routing protocol is Open Shortest Path First (OSPF), which automatically selects the optimal route for data packets based on received network topology information. The need for more advanced and scalable routing solutions led to the development of Multi-Protocol Label Switching (MPLS), introducing the concept of label switching for faster and more efficient data forwarding. This research aims to analyze the performance of OSPF and OSPF MPLS routing scenarios regarding TCP and UDP services. Through evaluation of Quality of Service (QoS) parameters, including throughput, packet loss, delay, and jitter. This study simulates the network using GNS3 software, with TCP and UDP services transmitted for durations of 15, 30, and 60 seconds. The results showed performance for both scenarios with an average index value of 3.75, indicating "good" network performance according to TIPHON standards across all measurement sessions. Although MPLS OSPF showed slightly lower throughput compared to non-MPLS OSPF, both scenarios showed very low packet loss, low delay, and stable jitter. The evaluation also highlights that the use of OSPF MPLS for UDP services reduces the time delay. Both non-MPLS OSPF and MPLS OSPF effectively support TCP and UDP services, with MPLS OSPF showing advantages in certain QoS parameters, especially for UDP services.

Streaming media transmission requires strict quality of service (QoS) parameters such as maximum delay and delay jitter. An effective streaming media routing algorithm is a key factor in ensuring QoS. The existing solution only considers a single parameter indicator in the performance parameters such as bandwidth, delay, and utilization of the link, and fails to comprehensively measure the data flow in the network. It is not possible to comprehensively measure the relationship between the business attributes and the QoS parameters. Firstly, the deterministic upper bounds of QoS parameters in streaming media networks are solved by using network calculus theory, and the QoS parameters are normalized, and a multi-constrained QoS resource allocation model is established; the separation of control and forwarding planes is defined by using software-defined networking (SDN) to deploy the multi-constrained QoS resource allocation model in the control plane; the QoS routing system of streaming media network based on the SDN is designed and implemented, including flow table scheduling model, routing function, measurement and forwarding modules. In the routing function module of the SDN controller, a multi-constrained QoS routing algorithm based on network calculus is implemented. Experimental results show that the proposed multi-constrained QoS resource allocation model based on network calculus and the multi-constrained centralized QoS routing algorithm based on the SDN have good performance.

In this paper, three routing protocols AODV, OLSR and ZRP are discussed and compared with their performance metrics for multiband transceiver by varying number of users, distance and number of packets. Simulations are performed by Qualnet 6.1 simulator, which concluded the performances of better routing protocol in the transceiver as compared to other and their comparison in the QoS parameters with the combination of power varying field.

QOS BASED CONTROL OF TELEOPERATION VIA INTERNET