Top PDF Using NSIS (Next Steps in Signaling) for support of QoS aware multimedia services

Using NSIS (Next Steps in Signaling) for support of QoS aware multimedia services

Using NSIS (Next Steps in Signaling) for support of QoS aware multimedia services

Transporting packet based network traffic, such as Internet Protocol [35], has tradi- tionally been a best-effort service. This means that each Internet Protocol (IP) packet receives the same treatment from routers and that any router it passes will process and transmit the packet as fast as possible, depending on the load on the router. However, in a world of IP convergence, demand has risen for different levels of services to be applied to different packets, so-called Quality of Service. In particular real-time streaming traf- fic such as multimedia services place stricter requirements on such parameters as packet loss and jitter. Over the years a number of solutions have emerged to implement QoS in IP networks in various ways, e.g. Integrated Services (IntServ) [21] and Differenti- ated Services (DiffServ) [20]. Each QoS solution defines its own set of service types and means of attributing these different service levels to different IP packets. Most of these QoS systems are based on static reservations within the own domain, used for example for Service Level Agreement (SLA)s. Several protocols, such as Resource ReSerVation Protocol (RSVP) [22], were developed to provide dynamic soft-state end-to-end reserva- tions, i.e. reservations for a flow from a sender to a receiver that may traverse several QoS domains and will expire after a certain period of time if not refreshed. This flow could be for example a Voice over IP (VoIP) session or a on-demand video stream. A conceptual depiction of this can be seen in Figure 1.1.
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End-to-End Quality-of-Service Support in Next Generation Networks with NSIS

End-to-End Quality-of-Service Support in Next Generation Networks with NSIS

Service Control Functions Resource and Admission Control Functions Transport functions CPE (UE) Service Stratum Transport Stratum Other NGNs SIP Signaling Path- Decoupled QoS Si[r]

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Comparison of End-to-End QoS Reservation Schemes in Next Generation Networks

Comparison of End-to-End QoS Reservation Schemes in Next Generation Networks

The state related to a data flow is installed and maintained on the NE along the data flow path through the network and it is not mandatory for all the nodes along the data path to have NEs. Either one or both of them can store some state information about the other but there is no assumption that they establish a long-term relationship. NSIS supports two basic paradigms for resource reservation signaling namely, Path-coupled signaling and Path- decoupled signaling. In Path-coupled singling, the signaling messages are routed only through the NEs that are on the data path. In Path-decoupled signaling, the signaling messages are routed to NEs that are not assumed in the data path but are aware of it. The current framework only concentrates on the path-coupled case. Signaling can be triggered by user applications, network management, network events etc. In NSIS, a wider variety of possible signal exchanges such as end-to-end, edge-to-edge and end-to-edge are supported. With NSIS, the signaling layer protocols in the NEs store per-flow state information. Signaling messages can be used to install, modify, refresh or read this information from the network elements. NSIS also provides the applications with the functionality of associating signaling messages pertaining to one or more data flows of an application session. This allows the support of scenarios where the data flows belonging to an application session have to be managed and treated together. New flows can be added and old ones can be deleted during the lifetime of a session.
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Partial session mobility in context aware IP based multimedia subsystem

Partial session mobility in context aware IP based multimedia subsystem

• It must be possible to integrate the node that iniates partial session transfers from the network in IMS. In IMS the component meant to offer services to the end-users is called the application server as described in section 3.2.2. An application server is allowed to act as a B2BUA, which means it is allowed to act on behalf of the end-nodes involved on the control layer. An application server thus has full control on the involved control- sessions, and thereby also on the configuration of the media-sessions. Because none of the currently available methods do already support integration in IMS as an application server, this requirement is not considered as an evaluation criteria for these methods. None of the current available methods do explicit support network initiated partial session transfer. However not every method is evenly able to be used for network initiated partial session transfers. Therefore the methods are evaluated by the possibility to support network initiated partial session transfers.
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Quality of Services (QoS) and Security Issues in Mobile Ad Hoc Networks (MANETs) – A Review

Quality of Services (QoS) and Security Issues in Mobile Ad Hoc Networks (MANETs) – A Review

Mobile Ad hoc Network (MANET) is a self-governing group of mobile nodes forming a self- motivated network and communicating over wireless links. Owing to its individuality such as easy deployment and self-organizing capability, it has great potential in many civil, military, real-time and a multimedia application is growing as well. These requests have Quality of Service (QoS) requirements and Security like bandwidth, end-to-end delay, jitter, energy, availability, authentication, integrity, and confidentiality. Consequently, it becomes very necessary for MANETs to have an efficient routing and QoS mechanism to support these applications. The emphasis of this paper is on exploring existing correlations for security and QoS issues in MANEs, the current issues and future challenges that are involved in this exciting area of research are also included.
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A guide for the selection of routing protocols in WBAN for healthcare applications

A guide for the selection of routing protocols in WBAN for healthcare applications

In the present scenario, the term wireless body area network (WBAN) is becoming an integral part of human day to day life due its wide variety of applications, especially in the field of healthcare systems. To design such a reliable body area network system, there are a number of factors to be considered both in hardware and software levels. One of such factors still developing is the design and the analysis of routing proto- cols in the network layer. Routing protocols are a set of protocols which can identify and maintain the routes in the network so that the data can be exchanged between the nodes efficiently. Hence, routing protocol plays a vital role in the wireless sensor networks for reliable communication between the sensor nodes. In this paper, differ- ent routing protocols for body area networks are surveyed and observed that they are affected by factors like energy, network topology, various quality of services (QoS) in the nodes, node temperature, transmission range of nodes, human posture, etc. An evocative taxonomy of protocols is presented such as cluster-based, cross-layered, postural movement based, QoS aware and temperature-aware routing protocols. From the survey, it is found that the selection of a routing protocol is application dependent. For example, the energy efficient protocols like reinforcement learning based routing with QoS support or wireless autonomous spanning tree protocol can be used for daily health monitoring systems due to its high packet delivery ratio. If the system is for in vivo networks, routing algorithm for network of homogeneous and Id-less biomedi- cal sensor nodes or mobility-supporting adaptive threshold-based Thermal-aware energy-efficient multi-hop protocols are the suitable ones. For critical and emergency cases, where accuracy with little delay is the major concern, the protocols like critical data routing, reliability aware routing, data-centric multi objective QoS-aware rout- ing protocol, etc. can be rightly chosen. This entire survey paper can be used by the researchers as a reference for studying various WBAN routing protocols, especially in the field of medical health care systems.
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A Publish/Subscribe Model for QoS aware Service Provisioning and Selection

A Publish/Subscribe Model for QoS aware Service Provisioning and Selection

The term “QoS” originates from the fields of telecommunications, distributed multimedia, and networking. QoS refers to a collection of qualities or characteristics of a service, such as availability, security, response-time, throughput, latency, reliability, and reputation. The arrangement between the customer and the service provider is referred to as the Service Level A greement (SLA). An SLA describes agreed service functionality, cost, and qualities [6]. Availability represents the percentage of time that the Web service is operating. Security characteristics comprise the authentication mechanisms that the service offers, encryption, and access control. The Web service provider may offer different security levels depending on the client’s request. Response-time is the time a service takes to respond to diverse types of requests. Throughput is the speed at which a service can process requests. Latency is the elapsed time between sending a request and receiving the response. Reputation is a qualitative measure of web services trustworthiness. It depends on the end-users’ experiences in using a Web service [7].
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A new Channel- and QoS-Aware scheduling Scheme for Real-time Services in LTE Network

A new Channel- and QoS-Aware scheduling Scheme for Real-time Services in LTE Network

LTE architecture defines a complete table with packet delay budget and packet loss rates for performing different service class in the network [1] which some or all may be executed by service provider. This table divides resource types in the LTE network into two groups, those are Guaranteed Bit Rate (GBR) and Non-GBR. In order to meet different QoS require- ments for these groups, several packet scheduling algorithms have been proposed. According to [7], the scheduling strate- gies for LTE downlink are divided into five groups including: (1) Channel-unware strategies, (2) Channel-aware/QoS-unaware strategies, (3) Channel-aware/QoS-aware strategies, (4) Semi- persistent scheduling for VoIP support, and (5) Energy-aware strategies. For the real-time services such as VoIP, Video, etc. which are very sensitive to delay and PLR. So that, the Channel- aware/QoS-aware strategies are very essential for them. Several well-known scheduling algorithms for this group as the Modi- fied Largest Weighted Delay First (M-LWDF) [6], the Exponen- tial/PF (EXP/PF) [16], the LOG and EXP rules [17] or the Frame Level Scheduler (FLS) [14]. In these schedulers, there is only the FLS which guarantees bounded delay for real-time flows, the re- maining schedulers transmits users data in a given Transmission Time Interval (TTI) by assigning a computed priority metric that is specific to the scheduler functionality. However, due to the lack of delay budget and PLR attribute, these schedulers are not suitable for supporting simultaneously real-time and non real- time traffic [5].
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A QOS AWARE MULTICAST ROUTING PROTOCOL FOR  CONSTRUCTING AN OPTIMAL PATH FOR MULTIMEDIA TRAFFIC IN WIRELESS SENSOR NETWORKS

A QOS AWARE MULTICAST ROUTING PROTOCOL FOR CONSTRUCTING AN OPTIMAL PATH FOR MULTIMEDIA TRAFFIC IN WIRELESS SENSOR NETWORKS

Abstract: Wireless Sensor Networks (WSNs) are communication networks having tiny sensors with sensing and transmitting capabilities .These systems adopting traditional routing protocols to organize communication, have design issues, and quality of service is still a challenging research factor. The key idea of this research is to discover the most efficient routing protocols based on the design of a reliable and efficient routing protocol to determine quality of services in a WSN. In this paper we propose a reliable and efficient path selection strategy by designing a Quality of Service Aware multicast routing protocol.This protocol discusses the multicast routing problem of WSN with multiple QoS constraints, by discovering a minimum resource consumption path while satisfying multiple constraints optimization conditions. Simulation results show that the fair link selection strategy can yield to a good solution for this traditionally NP complex problem, as compared to the best multicast algorithms known.
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Probabilistic analysis of QoS aware service composition with Explicit Environment Models

Probabilistic analysis of QoS aware service composition with Explicit Environment Models

In this paper, we present a model-based approach for QoS- aware service composition based on MDPs. We show how to obtain an MDP model based on the models of abstract and concrete services, and the environment model as a fully probabilistic system. Armed with probabilistic veri- fication, we are able to find the optimal service selection strategy against their QoS and the environment changes. The analysis can be made parametric with parametrised models for QoS of services and dynamics of environment changes, which makes them amicable to autonomous and self-adaptive systems. Our approach is based on a formal framework on a rigourous basis which provides a holis- tic, independent support for QoS-aware service compo- sition, including modelling, specification and automated synthesis of composition strategies and parameters. This model-based approach offers great flexibility, owing to the expressiveness of the MDP models we have adopted, and allows to take the environment into account explic- itly. One of the strengths of our approach is to provide, not only qualitative, but also quantitative analysis results, which is indispensable especially for the parametric anal- ysis. While bearing the modelling capability, as the exper- iments show, our framework is computationally feasible, and may demonstrate superiority in performance because of the optimised methods and tools to solve MDPs.
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A study of QoS Aware MAC Protocols for Wireless Multimedia Sensor Networks

A study of QoS Aware MAC Protocols for Wireless Multimedia Sensor Networks

Wireless Sensor networks can sense and process scalar data such as temperature, humidity, pressure etc. of the physical environment. Further the availability of inexpensive multimedia devices such CMOS camera and microphones have led to the development of wireless multimedia sensor networks [WMSN]. These multimedia devices can capture multimedia content such as scalar data, stream audio, and video from the environment. WMSN has gained popularity because of their flexibility of solving problems in different domains. They have potential to change our lives in many different ways. It is employed in wide range of application areas such as target detection and tracking, military and environmental mentoring. These applications are critical to the extent of saving Human life. Hence Reliable service and timely information is very important requirement in WMSN [2]. QoS in WMSN has some techniques and provide such reliable and authenticated information. But providing QoS support is a challenging issue due to highly resource constrained nature of sensor network, unreliable wireless links and harsh operation environments. The term QoS is extensively used in all the areas of computer networks. QoS helps to assign different priorities to different users, applications, packets, frames and dataflow based on their requirements by providing restricted resource sharing. Therefore high level of performance can be obtained through a set of measurable parameters such as delay, jitter, available bandwidth and packet loss.
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Cross layer QoS Support for Multimedia Delivery over Wireless Internet

Cross layer QoS Support for Multimedia Delivery over Wireless Internet

In addition to the adaptive ARQ, it is well known that priority-based packet scheduling can also support dif- ferential QoS services. In priority-based schedulers, pack- ets are grouped into several classes with different prior- ity according to their QoS requirements. Packets in the class with higher priority are more likely to be transmit- ted first. And packets in the same class are served in a FIFO manner. Based upon the priority scheduling mech- anism, each QoS class will have some sort of statistical QoS guarantees. Traditional priority packet-scheduling al- gorithms based upon generalized processor-sharing (GPS) fluid model such as weight fair queueing (WFQ) [90] in- herently couple delay bound and bandwidth requirement, which lack flexible QoS provision. Liao and Zhu [91] pro- posed a priority packet-scheduling algorithm by relaxing the packet service order. In [84], the authors employed the simplest strict (nonpreemptive) prioritized scheduling pol- icy and derived the rate constraints for different video sub- streams with different QoS requirements according to the EC theory [83]. The EC theory can also be applied to the QoS-provision scheme which exploits multiuser diversity [92]. The advantage of this scheme is that it can achieve capacity gain under strict QoS requirements where tradi- tional multiuser diversity scheduling cannot be applied di- rectly.
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Investigating a mobility-aware QoS model for multimedia streaming rate adaptation

Investigating a mobility-aware QoS model for multimedia streaming rate adaptation

2.1. Mobile Service Delivery. In the context of mobile ser- vices, network performance is typically evaluated from the perspective of the network by means of queueing analysis [1–3]. Although the study of wireless network performance from the perspective of the network can help in optimizing their performance and as a result the delivery of Internet services to mobile clients, there is currently no focus on evaluating the performance of networks from the perspective of an application or a service. To this end, a mobile service delivery framework has been proposed [4, 5] in the context of 5th generation networks such as Y-Comm [6] where reliable and constant connectivity is achieved at all times by means of seamless horizontal and vertical handovers. The proposed framework uses network mechanisms to constantly probe networks adjacent to the user and select the best possible connection that satisfies the requirements of the user’s applications. Thus far, only the traffic management aspects of the framework have been investigated through the use of Cloud technology for dynamic localization of services by means of Wide-Area-Network (WAN) migrations. In this paper, we explore the QoS aspects of the framework and therefore everything described in the following sections should be considered in the context of [4–6].
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Enhancement of QOS Aware Web Service Orchestration by Using CF Approach

Enhancement of QOS Aware Web Service Orchestration by Using CF Approach

Web services are open standard based web applications that interact with other web applications for the purpose of exchanging data. Web services can convert existing applications into web applications. The w3c defines a web service generally as: Web service is a software system designed to support interoperable machine-to-machine interaction over a network. Web services as an interface described in a machine-process format. Web services are services that are made available form a business web server for web user or other web connected program.
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Appraisal and Analysis on QoS Aware Secured Web Services over VANET Applications

Appraisal and Analysis on QoS Aware Secured Web Services over VANET Applications

Vehicular safety applications require periodic dissemination of status and emergency messages, contention based MAC protocols such as IEEE 802.11p have problems in predictability, fairness, low throughput, latency and high collision rate, especially in high density networks. Therefore, a distributed multichannel and mobility aware cluster-based medium access control (DMMAC) protocol is proposed. Through channel scheduling and an adaptive learning mechanism integrated within the Fuzzy Logic Inference System (FIS), vehicles organize themselves into more stable and non-overlapped clusters. Each cluster will use different sub channel from its neighbors in a distributed manner to eliminate the hidden terminal problem[22]. Increasing the system’s reliability, reducing the time delay for vehicular safety applications and efficiently clustering vehicles in highly dynamic and dense networks in a distributed manner are the main contributions of the proposed MAC protocol. The reliability and connectivity of DMMAC are analyzed in terms of the average cluster size, communication range within the cluster and between cluster heads, and the life time of a path. Simulation results show that the proposed protocol can support traffic safety
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A QoS aware Method for Web Services Discovery

A QoS aware Method for Web Services Discovery

Web Service Description Language (WSDL) is an XML format for describing network services as a set of endp- oints operating on messages containing either document- oriented or procedure-oriented information[7]. Specifica- lly, it defines via its portType component, the Web serv- ice's abstract interface, specifying the operations that the service supports and for each operation, the format of the messages that the service sends and receives. The client programs read the WSDL files to connect and comm- unicate with the service. The current WSDL file contains the following information: the number of inputs and outputs, the variable type of each input and output, the order the inputs are given and outputs are returned, and how the Web service should be invoked. But from the WSDL file, we can not get the QoS information. To solve this problem we propose to extend the WSDL to support the QoS information description.
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Improving WLAN Quality of Services (Qos) Using Opnet

Improving WLAN Quality of Services (Qos) Using Opnet

Wireless local area networks (WLANs) are in a period of great expansion and there is a strong need for them to support multimedia applications. With the increasing demand and penetration of wireless services, users of wireless networks now expect Quality of Service (QoS) and performance comparable to what is available from fixed networks. Providing QoS requirements like good throughput and minimum access delay are challenging tasks with regard to 802.11 WLAN protocols and Medium Access Control (MAC) functions. This research is done to study, the presently implemented schemes (the Point Coordination Function (PCF) of IEEE 802.11, the Enhanced Distributed Coordination Function (EDCF) of the proposed IEEE 802.11e extension to IEEE 802.11), solves these issues and what can be done to improve them further. The metrics used were Throughput, Data Drop, Retransmission and Medium Access Delay, to analyze the performance of various MAC protocols in providing QoS to users of WLAN. Two scenarios, with same Physical and MAC parameters, one implementing the DCF and other EDCF, were created in the network simulation tool (OPNET MODELER) to obtain the results. The results showed that the performance of EDCF was better in providing QoS for real-time interactive services (like video conferencing) as compared to DCF, because of its ability to differentiate and prioritize various services. Index Terms - Wireless local area networks (WLANs),
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QoS Aware Active Queue Management for Multimedia Services over the Internet

QoS Aware Active Queue Management for Multimedia Services over the Internet

Recently, with multimedia services such as IPTV, video conferencing has emerged as a main traffic source. When UDP coexists with TCP, it induces not only congestion collapse but also an unfairness problem. In this paper, a new Active Queue Management algorithm, called Traffic Sensitive Active Queue Management (TSAQM), is proposed for providing multimedia services in routers. The TSAQM is comprised of Dynamic Weight Allocate Scheme (DWAS) and Service Guarantee Scheme (SGS). The purpose of DWAS is to fairly allocate resources with high end-user utility, and the SGS is to determine the satisfactory threshold (TH) and threshold region (TR). Besides, a multiqueue design for different priority traffic, and threshold TH and threshold region TR is proposed to achieve the different QoS requirements. Several objectives of this proposed scheme include achieving high end user utility for video services, considering the multicast as well as unicast proprieties to meet interclass fairness, and achieving the QoS requirement by adaptively adjusting the thresholds based on the traffic situations. Performance comparisons with the GRED-I are in terms of packet dropping rate and throughput to highlight the better behavior of the proposed schemes due to taking into account the fairness and different weights for video layers.
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Simulation Study On IP-QoS Videoconferencing Performance Using Opnet Modeler

Simulation Study On IP-QoS Videoconferencing Performance Using Opnet Modeler

The deployment of Videoconferencing also known as Video and Voice over IP (VVoIP), over existing IP networks is gaining popularity these days. The Quality of Services (QOS) is one of most important areas of Internet development and support represent one of the most important features of modern multimedia networks. As the Internet originally developed for data communications is now used more and more for real-time applications. Since QoS support technologies are still objects of intensive development and fine tuning, simulations and modeling are highly required in this field. This paper presents the simulation study on IP-QoS videoconferencing performance using OPNET MODELER and to propose a method to proven that the quality of services (QoS) system is very important in Ethernet network. For this project, topology was built using the same system parameters with two different scenarios to see the comparison impact quality of services that occurred in the both scenario. Accompanying for this project, the final simulation results will show which scenario has the best performance in quality of services (QoS).
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Delay based and QoS aware packet scheduling for RT and NRT multimedia services in LTE downlink systems

Delay based and QoS aware packet scheduling for RT and NRT multimedia services in LTE downlink systems

delay–aware scheduling rule named Modified–Largest Weighted Delay First (M–LWDF) by [8] was initially pro- posed for CDMA mobile systems, and yet, has been vastly adopted in LTE. The idea behind M–LWDF depends on flows delay that is measured from the flow Head of Line (HoL) delay. Besides, it adopts the PF behavior to enforce a fair service level between different flows. In fact, like M–LWDF, many other works also rely on PF con- cept’s properties 1 to invoke their scheduling decisions. For instance, authors in [20] extended the PF concept to a delay–based scheduler where buffer status in current and previous scheduling interval is accounted. The schedul- ing rule emphasizes on fair delay distribution instead of actually minimizing delay time. In [21], PF is joined with a user–defined delay threshold below the maximum bound and a ratio of allocated resource blocks are utilized to design a scheduling rule. Although low delay can be estab- lished, ensuring a long–term low delay during the network overload states using the statically determined parame- ters tends to be an elusive goal, especially, in case of burst Variable Bit Rate (VBR) traffic where long buffers are com- mon. Besides, in another proposal [22], flows urgency level is defined using thresholds of minimum and maxi- mum delay bounds; this allows the delay–based algorithm with a scheduling decision that favors highly urgent flows. The known EXPonential–PF (EXP–PF) in [23] shows a decent behavior of QoS in both RT and NRT traffic. EXP–PF benefits from the PF principle to keep an oppor- tunity for NRT to be scheduled, meanwhile maintaining low delay bounds on certain RT traffic 2 by employing
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