A New Heuristic Metatask Scheduling Algorithm Based on Choosing QoS Policy Mechanism

차별화 서비스(DiffServ)는 효율적이며 규모성을 갖는 방법으로 서비스 품질(QoS)을 제공하는 기술이다. 그러나, 현재의 차별화 서비스 규격들은 완전한 QoS 관리 프레임워크와 구현 모델의 제공에는 취약한 실정이다. 본 논문은 차별화 서비스 망의 QoS를 관리하기 위하여 차별화 서비스 정책을 지원하는 정책 기반 차별화 서비스 QoS 관리 모델을 제안한다. 이 모델을 모델-뷰-컨트롤러(MVC) 구조를 따르며, EJB(Enterprise JavaBeans) 기술에 기반을 두고 있다. 우리의 모델에서 상위 레벨 차별화 서비스 QoS 정책들은 XML 스키마를 갖는 유효한 XML 문서들로 표현되고 EJB 기반 정책 서버 내에 하위 레벨 EJB 정책 번들로 변환된다. QoS 정책을 정의하기 위해 필요한 라우팅 형상과 라우터의 역할 정보 검출은 SNMP MIB-II를 사용하고, QoS 정책 분배와 모니터링은 SNMP DiffServ MIB를 사용한다. Differentiated Services (DiffServ) is a technique to provide Quality of Service (QoS) in an efficient and scalable way. However, current DiffServ specifications have limitations in providing the complete QoS management framework and its implementation model. This paper proposes a policy-based QoS management model that supports DiffServ policies for managing QoS of DiffServ networks. The management model conforms to Model-View-Controller (MVC) architecture, and is based on Enterprise JavaBeans (EJBs) technologies. In our model, high-level DiffServ QoS policies are represented as valid XML documents with an XML Schema and are translated to low-level EJB policy beans in the EJB-based policy server. The routing topology and role information required to define QoS policies is discovered by using SNMP MIB-II, and the QoS policy distribution and monitoring is accomplished by using SNMP DiffServ MIB.

A network management system (NMS) is a vital tool to be used in a corporate network. It ensures that Quality of Service (QoS) policies are correctly applied, but can also have a great impact over the network security preventing attacks and blocking the ongoing actions of attackers in enterprise networks. The current work presents an implementation of an out-of-band NMS with the primary purpose of detecting and blocking ongoing Domain Name System (DNS) exfiltration attacks which are triggered by other hosts in the network. The secondary purpose of the NMS is to adjust the QoS policies of the other devices in the network manipulating the value of the DifferentiatedServices (DiffServ) field of the IP packets. The solution is implemented using the SharpPcap framework for automated packet processing with the desire to make this system open source for further development. An experimental setup was created using a wiretap for traffic duplication to an out-of-band monitoring device. The experimental work proves that the solution is effective in detecting dictionary-based DNS exfiltration attacks and is successful in blocking the attacker from the network.

The ITU-T defined next generation network (NGN) architecture designates the resource admission control function to perform the application-driven Quality of Service (QoS) control across access and core networks. The Generalized Multiprotocol Label Switching (GMPLS) was introduced by the Internet Engineering Task Force (IETF) to cope with new traffic engineering challenges in fast optical networks and provide them with reliable end-to-end QoS mechanisms. However, an actual Connection Admission Control (CAC) implementation inside the resource reservation protocol - traffic engineering extension (RSVP-TE) in GMPLS networks does not provide the ability of effective decision making, since the applied threshold CAC lacks of the capability to consider QoS policies on GMPLS network nodes. This prevents an effective end-to-end QoS control in a fully dynamic, application driven Label Switched Path (LSP) setup scenario. This work presents a specific implementation of fuzzy-CAC operating over an RSVP-TE agent in GMPLS network domain. This fuzzy-CAC implementation is applied to a testbed where a client application requests a real-time data transfer through a GMPLS network, which results in dynamic LSP setup and exclusion. The admission control is performed upon service request based on QoS class requirements and network resource availability. The differentiated traffic treatment on per-flow basis is realized through employment of IF-THEN rule based expert knowledge. Effective traffic differentiation is achieved in a multi-service network scenario and thus it validates fuzzy-CAC as candidate for RSVP-TE protocol enhancement for application driven QoS provisioning in GMPLS networks.

This paper provides three contributions to the study of quality of service (QoS) configuration in component-based DRE systems. First, we describe the challenges associated with mapping the platform-independent QoS policies of an application into platform-dependent values of QoS parameters used to configure the behavior of QoS-enabled component middleware. Second, we describe a novel approach that uses model-transformation to map these QoS policies onto component middleware QoS configuration parameters. Third, we demonstrate the use of model-checking to verify the properties of the transformation and automate the synthesis of configuration parameters required to tune the QoS-enabled component middleware. Our results indicate that model-transformation and model-checking provide significant benefits with respect to automation, reusability, verifiability, and scalability of the QoS mapping process compared with conventional middleware configuration techniques

Configuring routers and network devices to achieve quality of service (QoS) goals is a challenging task. In a DiffServ environment, traffic flows are assigned specific classes of service, and service level agreements (SLA) are enforced at routers within the domain. We present a model for QoS policy configurations that facilitates efficient property-based verification. Network configuration is given as a set of policies governing each device. The model efficiently checks the SLA against the current configuration using computation tree logic model checking. By following possible decision paths for a specific flow from source to destination, properties can be checked at each hop, and assessments can be made on how well configurations adhere to the specified agreement. The model also covers configuration debugging given a specific QoS violation.

Tactical networks are constrained networks that may transition between ad-hoc and mesh configurations and are characterised by frequent disruptions, changes in connectivity, and available resources. Whilst deploying a service-oriented architecture (SOA) allows the efficient provisioning of services at the tactical level, the existing resource limitations and potential attacks, require the dynamic adaptation of both quality of service (QoS) and security mechanisms. Within this environment, security and QoS must not only enforce the requisite functionalities, but also cooperatively seek optimal solutions for them according to their corresponding constraints and requirements. In this paper we propose a multi-domain policy-based decision subsystem supporting service delivery, that relies on an online knowledge-based reasoning mechanism. We describe the characteristics of such subsystem and show its benefits in relation to specific tactical requirements.

We consider the scheduling problem in a new slotted optical network called TWIN. The TWIN architecture possesses interesting properties, which may offer solutions for next-generation optical networks. Besides, TWIN has the ability to support quality of service (QoS) by controlling two important parameters: queueing delay and delay variance. However, to the best of our knowledge, the existing scheduling algorithms in TWIN focused mainly on maximizing the throughput and ignored the consideration of QoS. We formulate the scheduling problem into an integer linear programming problem and propose a heuristic--virtual topology-based dynamic scheduling (VTBDS) algorithm to solve it fast and efficiently. Besides, we derive an analytical model for TWIN and investigate the performance of VTBDS in it. By means of simulations, we demonstrate that our model approximates the TWIN network very well, and VTBDS incurs smaller queueing delay and delay variance, which are advantageous for guaranteeing better QoS.

This paper proposes novel resource sharing schemes for differentiated services (DiffServ) networks, to achieve both high resource utilization and quality of service (QoS) guarantee. Service level agreements (SLAs) are negotiated at network boundaries and supported by path-oriented resource mapping within the network. The recently proposed SLA management scheme based on virtual partitioning (Bouillet et al., 2002) allows overloaded SLAs to exploit the spare capacity of underloaded SLAs for efficient resource utilization, however, at the the cost of possible SLA violation of the underloaders. In the bandwidth borrowing scheme proposed here, the dedicated bandwidth for underloaded SLAs is determined and adaptively adjusted at network boundaries according to the actual traffic load and QoS policies; the available spare capacity is then properly distributed to related links for lending to others. On the other hand, the traffic flows admitted with borrowed bandwidth are tagged and may be preempted later when the original bandwidth owner needs to claim back the resources. Through a detailed implementation design and extensive computer simulation results we show that, by bandwidth borrowing, both SLA compliance and high resource utilization can be achieved in various load conditions, with some side benefits such as call-level service differentiation, small admission overhead, and convenience for policy-based management. In addition, we propose a distributed bandwidth pushing scheme that can dynamically adjust the spare bandwidth distribution over the network. Combining bandwidth pushing with bandwidth borrowing, the resource utilization can be further improved.

Dynamic inter-domain collaborations and resource sharing comprise two key characteristics of mobile Grid systems. However, inter-domain collaborations have proven to be vulnerable to conflicts that can lead to privilege escalation. These conflicts are detectable in inter-operation policies, and occur due to cross-domain role relationships. In addition, resource sharing requires to be enhanced with resource usage management in virtual organizations where mobile nodes act as resource providers. In this case the enforcement of resource usage policies and quality of service policies are required to be supported due to the limited capabilities of the devices. Yet, the ANSI INCITS 359-2004 standard RBAC model provides neither any policy conflict resolution mechanism among domains, nor any resource usage management functionality. In this paper, we propose the domRBAC model for access control in mobile Grid systems at a low administrative overhead. The domRBAC is defined as an extension of the standardized RBAC by incorporating additional functionality to cope with requirements posed by the aforementioned systems. As a result, domRBAC facilitates collaborations among domains under secure inter-operation, and provides support for resource usage management in the context of multi-domain computing environments, where mobile nodes operate as first-class entities.Keywordsmobile Gridrole based access control (RBAC)secure inter-operationresource usage managementcross-domain authorization

Long Term Evolution (LTE) is a main mobile communication technology in the future. For the reason that different kinds of multimedia applications have different quality of service (QoS) requirements, especially for Real Time (RT) traffics, it is necessary to design an effective scheduling algorithm to satisfy the various kinds of QoS needs. In this paper we propose a new scheduling algorithm named DP-VT-MLWDF. The simulation results of the proposed scheduler indicate an evident improvement of the QoS performance parameters for RT traffics, e.g., packet loss rate, average throughput, fairness index.

The LTE specification provides Quality of Service (QoS) of multimedia services with fast connectivity, high mobility, and security. However, 3GPP specifications have not defined scheduling algorithms to support real-time and non-realtime application services, this has led to the development of a variety of scheduling algorithms in the recent years. Performance is a key factor for assessing the scheduling algorithms. However, the performance analysis and evaluation for existing scheduling algorithms are limited to QoS parameters (e.g. in terms of throughput, packet loss and delay) and/or fairness metrics. It is not clear how these scheduling algorithms perform in terms of Quality of Experience (QoE) metrics (e.g. MOS score) which are more closely linked with end user experience or user perceived quality. In this paper, we investigate and evaluate the performance of three popular LTE downlink schedulers (proportional fairness (PF), exponential proportional fairness (EXP-PF), and modified largest weight delay first (M-LWDF)) in terms of QoE metric (i.e. MOS score) in addition to normal QoS metrics (e.g. packet loss and delay) for VoIP applications. Simulation results (based on LTE-Sim) show that the best suitable downlink scheduling algorithm is MLWDF, which has short end-to end delay (less than 50ms) and allowing maximum number of user access (more than 50 users) at acceptable MOS score (MOS over 3.5). The widely used scheduling algorithm (PF) will increase its end-to-end delay over 200ms, when number of user access is over 30. This will limit its application for VoIP when user access number increases. This work would help to assist the design and development of QoE-driven scheduling algorithms for mobile multimedia applications in the future.

Many applications involve the concepts of scheduling, such as communications, packet routing, production planning [Zhai et al., 2006], classroom arrangement [Mathaisel & Comm, 1991], aircrew scheduling [Chang, 2002], nurse scheduling [Ohki et al., 2006], food industrial [Simeonov & Simeonovova, 2002], control system [Fleming & Fonseca, 1993], resource-constrained scheduling problem [Chen, 2007] and grid computing. There are many different types of scheduling problems such as real-time, job-shop, permutation flow-shop, project scheduling and other scheduling problems have been studied intensively. However, in this work, the studied grid task scheduling problem is much more complex than above stated classic task scheduling problems. Restated, a grid application is regarded as a task scheduling problem involving tasks with inter-communication and distributed homogeneous or heterogeneous resources, and can be represented by a task interaction graph (TIG). Grid is a service for sharing computing power and data storage capacity over the Internet. The grid systems outperform simple communication between computers and aims ultimately to turn the global network of computers into one vast computational resource. Grid computing can be adopted in many applications, such as high-performance applications, large-output applications, data-intensive applications and community-centric applications. These applications major concern to efficiently schedule tasks over the available multi-processor environment provided by the grid. A grid is a collaborative environment in which one or more tasks can be submitted without knowing where the resources are or even who owns the resources [Foster et al., 2001]. The efficiency and effectiveness of grid resource management greatly depend on the scheduling algorithm [Lee et al., 2007]. Generally, in the grid environment, these resources are different over time, and such changes will affect the performance of the tasks running on the grid. In grid computing, tasks are assigned among grid system [Salman, 2002]. The purpose of task scheduling in grid is to find optimal task-processor assignment and hence minimize application completion time (total cost). Most scheduling problems in these applications are categorized into the class of NP-complete problems. This implies that it would take amount of computation time to obtain an optimal solution, especially for a large-scale scheduling problem. A variety of approaches have been applied to solve scheduling problems, such as

WiMAX refers to Wireless Interoperable implementations of the IEEE 802.16 standards ratified by the WiMAX Forum has a main goal to deliver wireless communications with quality of service in a secured environment. The WiMAX MAC layer is designed to support different types of applications and services having different Quality of service (QoS) requirements. In addition of providing higher throughput and less delay, a scheduling algorithm should also take into account the WiMAX Qos classes and service requirements at MAC layer. Proper scheduling algorithm will enhance the date rate of all the QoS classes of IEEE 802.16e standard. The problem of the scheduler is that there is no standard algorithm that will satisfy all the QoS parameters of IEEE 802.16e standard. We aim to highlight a problem of real-time (UGS a rtPS) service class and provide a feasible solution to it by directing our focus towards the real-time classes. We propose a review of uplink scheduling algorithms proposed for WiMAX and the problems connected with it. The solution to the proposed problem is that we structure a Cross layered hybrid up-link algorithm. NS3 simulations will lead us with interesting results and thus enhance throughput and minimize delay and jitter.

This study aims to improve the performance of message data transmission in Aggregated Robot Processing (ARP) architecture where the RELIABLE option of the RELIABILITY QoS (Quality of Service) policy is applied to a ROS 2 (Robot Operating System 2) node communication. Basically, the RELIABLE option guarantees that a publisher properly send all message data to a subscriber. However, the publisher could fail to transmit some message data to the subscriber even in the RELIABLE QoS option unless the buffer size of the publisher is enough. We introduce local cache to a sensing component to alleviate the issue in the case that the sensors output the same value in a row. The experimental results showed that the local cache improved the latency and reduced the message loss in node communication.

SummaryNext generation wireless networks consist of many heterogeneous access technologies that should support various service types with different quality of service (QoS) constraints, as well as user, requirements and provider policies. Therefore, the need for network selection mechanisms that consider multiple factors must be addressed. In this paper, a network selection method is proposed by applying the analytic network process to estimate the weights of the selection criteria, as well as a fuzzy version of technique for order preference by similarity to ideal solution to perform the ranking of network alternatives. The method is applied to a heterogeneous network environment providing different QoS classes and policy characteristics. Each user applies the method to select the most appropriate network, which satisfies his or her requirements in respect of his or her service‐level agreement (SLA). Performance evaluation shows that when the user requests only one service, the proposed method performs better compared to the original technique for order preference by similarity to ideal solution, as well as the Fuzzy AHP‐ELECTRE method. Moreover, the proposed method can be applied in cases where a user requires multiple services simultaneously on a device. The sensitivity analysis of the proposed method shows that it can be properly adjusted to conform to network environment changes. Copyright © 2014 John Wiley & Sons, Ltd.