COPS-SLS: a service level negotiation protocol for the Internet

The deployment of QoS over the Internet may achieve protocols for the negotiation of service levels, as well as mechanisms for the end-to-end realization of service level agreements. Such general-purpose protocols include Common Open Policy Service (COPS) for policy specification within a domain. This article proposes an extension of the COPS protocol for intra- and interdomain service level negotiation. The proposed protocol is known as COPS-SLS. This allows the configuration of domain policies regarding service levels, and the automatic negotiation of service levels within the domain policies     

Service level negotiation andcops-sls protocol

The Internet is a set of interconnected domains in which different QoS technologies can be deployed. The dynamic provision of end-to-end QoS over heterogeneousip networks assumes the negotiation of mutually acceptablesla. This paper presents the concept of intra-, inter- and multiple-domain service level negotiation using thecops-sls protocol. The negotiation process gives different parties in the negotiation the ability to agree upon the service level that a data stream can obtain, along with the permissible pricing of the service.     

End-to-end quality-of-service coordination for mobile multimedia applications

Transmitting real-time multimedia streams over heterogeneous mobile networks is a challenging task. Variation in network and system conditions can dramatically affect application performance. When providing end-to-end quality-of-service (QoS) multiple system facets should be coordinated: orchestration of local and peer resources, reservation of network resources, adaptation of multimedia streams, etc. This paper presents an end-to-end negotiation protocol (E2ENP) for negotiating and coordinating QoS on an end-to-end basis both at application and network layer. Based on a flexible extensible markup language (XML) model and extending SDPng concepts, the protocol enables the negotiation of system capabilities and allows provider-services to effectively influence the negotiation process. The aim of the E2ENP design is to optimize the efficiency of multimedia call setup and reduce the time for QoS renegotiations, whenever vertical handovers or spontaneous network reconfigurations occur. The basic protocol is presented, together with implementation and measurement results, stemming from several studies on current and future third-generation/fourth-generation scenarios.     

A CORBA-based quality of service management framework fordistributed multimedia services and applications

For distributed multimedia services, it is essential that quality of service be guaranteed system-wide, including end systems, communication systems, and networks. Although many researchers have addressed issues of QoS management, little attention has so far been paid to the QoS management services in distributed multimedia services and applications. To address this deficiency, we have designed a layered model for end-to-end QoS management called the QoS management framework. Our framework, which is CORBA-based, includes a generic QoS MIB for the QoS parameterization of various multimedia services and the services needed to perform various QoS functions. A key component of this framework is the QoS management service object (QMSO), which orchestrates resources at endpoints, coordinating resource management across layer boundaries. Services such as translation, monitoring, admission, and negotiation are provided by the QMSO. To validate this concept, we have developed a QoS management system for managing and controlling the QoS of a distributed multimedia system called MAESTRO. The QoS management system has been implemented through CORBA objects and provides an interface to multimedia applications, which can be dynamic negotiation and renegotiation of QoS by users. Some performance results in QoS negotiation and renegotiation are also presented     

End-to-end QoS specification issues in the converged all-IP wired and wireless environment

The emerging next-generation networking environment presents an IP-based core interconnecting many wireless radio access networks, providing ubiquitous access to end users through a vast variety of wireless devices. Although the IP protocol is the common denominator, the new environment brings together many different interconnecting domains, each following different QoS models, complicating the overall end-to-end QoS process. This article discusses the need to standardize an end-to-end QoS protocol. It does not, however, focus on the signaling mechanism, since there is currently a relevant ongoing activity in IETF. Instead, it concentrates on the formulation of the QoS information describing the QoS requirements of the session to be established. It presents the generic service specification framework that not only enables the QoS requirements of a specific session to be captured (like a generic QoS template), but also the QoS classes of each IP domain can be described according to it. Through the systematic specification of a domain's QoS classes, an intelligent automatic mapping algorithm can be applied during an end-to-end QoS request, in order to select the most appropriate service class in each domain, as well as to extract the required traffic-related parameters to perform traffic control operations, such as admission control, policing, and scheduling.     

End-to-end service level negotiation protocol for self-management networks

We propose a framework for service level negotiation within s elf-management systems. The negotiation process occurs between high-level autonomic managers to guarantee an end-to-end service level for specific application traffic flows. In the proposed framework, we provide autonomic systems with a new interaction opportunity thanks to the negotiation with their peers. To be in conformance with the concepts of self-aware management systems, the proposed negotiation protocol called SLNP is used in a Web Services environment.     

浅谈无线IP网络中的QoS规范

随着下一代网络的飞速发展,用户之间可以通过多种多样的无线设备相互联络,而这些无线设备则通过一个基于IP的核心网络所提供的无线链路相互连结的。虽然存在如IP协议之类的共同规范,但是要将许多不同的网络融合起来,而这些网络有着各自不同的QoS模型,这无疑将使端到端的QoS保证变得更加复杂。文中讨论了对端到端QoS协议进行标准化的必要性,重点研究了位于服务层的QoS规范,提出了一种通用服务规范(GSS),并对端到端提供QoS保证的服务等级进行了规范。     

A quality-of-service signaling architecture for seamless handover support in next generation,IP-based mobile networks

The coupling of signaling protocols for mobility management and resource reservation plays an important role to achieve Quality-of-Service (QoS) in wireless environments. When performing a handover, request and allocation of resources have to be done in the shortest possible time to avoid disruptions for the user service. Therefore, it is preferable to ensure resource availability in advance, which we call anticipated handover. This approach for providing seamless handovers in turn poses challenges for the overall design of the QoS architecture and its associated QoS signaling protocol. This article describes the design, implementation, and evaluation of a comprehensive QoS architecture and a suitable QoS signaling protocol. It discusses intrinsic problems of reservations in IP based networks such as session ownership as well as a number of protocol design issues regarding the integration of QoS signaling with other protocols, such as Mobile IP. In particular, we define an end-to-end QoS architecture and a mobility-aware reservation signaling protocol Mobility Aware Reservation Signaling Protocol (MARSP) that supports anticipated handover, thus enabling seamless services over heterogeneous wireless access networks. The presented architecture and protocol were implemented and evaluated by measurements. They show that anticipated handovers not only outperform hard handovers regarding handover latency, but that they also provide functional and robustness advantages. Authors Hillebrand and Prehofer changed their affiliation in the meantime, the work described in this paper was carried out during their employment at DoCoMo Communications Laboratories Europe.     

QoS management in mobile IP networks using a terminal assistant

This paper describes a signalling environment for Quality of Service (QoS) negotiation and advance resource reservation in mobile IP networks. This environment is built in conformance with the generic signalling environment, which is standardized by the NSIS IETF working group. The advanced resource reservation protocol, called MQoS NSLP, is based on the QoS NSLP signalling application. It provides to mobile terminals the QoS required based on the user's mobility and QoS profile. In this work, we investigate the use of some techniques of the AI (Artificial Intelligence) domain to implement a user interface called NIA (Negotiation Individual Assistant) in order to determine the QoS profile and negotiate the QoS parameters in the new domain after the handover. Therefore, we use connectionist learning in the management of the negotiation profiles and agent technology to help the user choose the best service provider, dynamically negotiate the QoS on the user's behalf, and follow the user's behaviour to be able to anticipate the negotiation and manage renegotiation. The advance resource reservation is based on an object MSpec (Mobility Specification) which determines the future location of the mobile terminal. The MSpec object is a part of the mobility and QoS profile and is determined by the NIA in the mobile terminal. Copyright © 2008 John Wiley & Sons, Ltd.     

Enabling End-to-End QoS over Hybrid Wired-Wireless Networks

Providing end-to-end parameterized QoS is desirable for many network applications and has received a lot of attention in recent years. However, it remains a challenge, especially over hybrid networks involving both wired networks and wireless access segments (such as IEEE 802.11 Wireless Local Area Networks (WLANs)). The difficulty in achieving such QoS arises mainly because wireless segments often constitute “gaps" in terms of resource guarantee, due to the lack of efficient resource scheduling and management ability over shared wireless media, as well as the lack of an appropriate QoS signaling interface to seamlessly embed these wireless segments into an end-to-end QoS signaling system. In this paper, we consider the scenario where an IEEE 802.11 wireless node wishes to make an end-to-end resource reservation to a remote wired Internet node and vice versa. We propose Wireless Subnet Bandwidth Manager (Wireless SBM), an extension of SBM protocol to WLANs, to provide seamless end-to-end resource reservations. Wireless SBM utilizes the enhanced resource management ability provided by Hybrid Coordination Function (introduced in the upcoming IEEE 802.11e standard) to provide parameterized resource reservation and admission control.     

End-to-end QoS resource management for an IP-based DWDM access network

The ever-increasing use of broad-band Internet and complex multimedia applications is pushing fiber closer and closer to the homes. Within the European project IST HARMONICS (Hybrid Access Reconfigurable Multi-wavelength Optical Networks for IP-based Communication Services), an optical access feeder network and resource management framework were developed that tackle this demand for bandwidth and the desire to stimulate the convergence of last-mile access technologies. To cope with the lack of bandwidth in the access and last-mile networks and the different needs of applications and users, the developed management system provides end-to-end quality of service (QoS) while integrating multiple technologies. In this paper, a detailed overview of the end-to-end QoS management framework and novel time slot/wavelength MAC protocol for the optical feeder network is given. End-to-end QoS is based on Differentiated services (DiffServ) at layer 3, various QoS supporting technologies at layer 2, and QoS mappings between both layers. The paper will also focus on the field trial results of the HARMONICS project and give some guidelines for possible problems and solutions in this area.     

Quality of service in telecommunications .II. Translation of QoSparameters into ATM performance parameters in B-ISDN

The main goal of this article is to present the translation of quality of service (QoS) parameters between layers. The QoS parameters in the ATM layer and AAL are defined. This translation concept came from the QoS framework in which the influence of the protocol stack on the QoS should be considered. As an example, we concentrate on the translation from the AAL to the ATM layer, as the AAL must be designed to be service-dependent and specific. Translation, both taking the transport protocol into account as well as between application and transport QoS, needs further study. However, our study shows that the QoS translation is a possible and good approach in end-to-end QoS guarantees in the broadband integrated services digital network (B-ISDN). As far as the end-to-end QoS guarantee issue is concerned, the transport QoS requirements are specified in terms of bounds on transport QoS parameters. The bounds on transport QoS parameters will be translated into the bounds on ATM layer QoS parameters. The ATM-layer QoS parameters resulting from the translation will be the performance requirements on a connection basis for the ATM network, but are basically the end-to-end parameters, including the network and the end systems. Therefore, the QoS translation finally results in the network performance parameters in the ATM network. We define QoS parameters in the AAL and ATM layer. Case studies in which the translation method is applied to a constant bit rate (CBR) video service and data service, respectively, are also presented     

Distributed Busacker–Gowen algorithm for end-to-end QoS pipe negotiation in X-domain networks

Multimedia services and other critical multisite services (e.g., VPN) are becoming mainstream, and they require a guaranteed quality of service (QoS). Services need to be established across several autonomous systems (ASes), often to connect end-users. Thus, provisioning and control of end-to-end QoS requirements arise as one of the main challenges in inter-AS management. The contractual approach, consisting in using service-level agreements (SLAs) defined by each crossed AS, allows to negotiate contract chains that satisfy end-to-end requirements. However, establishing such chains by on-demand negotiations does not scale up for large numbers of requests. Hence, we propose a negotiation process to occur before users’ requests to establish service are received. The proposed negotiation process results in the selection of aggregated contract chains, called pipes, and a distribution between them. Such a distribution would indicate, for each chain of a pipe, the connection flow it may accept. In this paper, we address the pipe negotiation problem as a network flow problem. We also propose a distributed adaptation of an algorithm for network flow problems.     

Principles of QoS in group communications

In this paper, we consider QoS support in the context of group communications. In particular, we present fundamental properties of QoS in group communications, which, although quite simple, have been widely overlooked and/or misunderstood. Because distributed multimedia applications require flexible QoS agreements, end-to-end QoS negotiation will play an important role. We show how such a negotiation mechanism can be designed, taking the fundamental QoS properties into account. This leads us to the design of an algorithm for QoS negotiation whose computational overhead proves to be independent of the size of the group of receivers.     

FTT-Ethernet: a flexible real-time communication protocol that supports dynamic QoS management on Ethernet-based systems

Ethernet was not originally developed to meet the requirements of real-time industrial automation systems and it was commonly considered unsuited for applications at the field level. Hence, several techniques were developed to make this protocol exhibit real-time behavior, some of them requiring specialized hardware, others providing soft-real-time guarantees only, or others achieving hard real-time guarantees with different levels of bandwidth efficiency. More recently, there has been an effort to support quality-of-service (QoS) negotiation and enforcement but there is not yet an Ethernet-based data link protocol capable of providing dynamic QoS management to further exploit the variable requirements of dynamic applications. This paper presents the FTT-Ethernet protocol, which efficiently supports hard-real-time operation in a flexible way, seamlessly over shared or switched Ethernet. The FTT-Ethernet protocol employs an efficient master/multislave transmission control technique and combines online scheduling with online admission control, to guarantee continued real-time operation under dynamic communication requirements, together with data structures and mechanisms that are tailored to support dynamic QoS management. The paper includes a sample application, aiming at the management of video streams, which highlights the protocol's ability to support dynamic QoS management with real-time guarantees.     

Architecture for mobility and QoS support in all-IP wireless networks

Mobility management and quality-of-service (QoS) provisioning are the important tasks on the future development of wireless networks. The high host mobility makes these tasks more challenging. In this paper, we propose an architecture which supports both mobility and QoS management in Internet protocol (IP)-based wireless networks. In mobility management, the fast handoff, which the packets are forwarded in advance to the neighboring locations where a mobile node (MN) may move to, is provided to reduce the service disruption. Also, the fast location lookup, which the routing information about a MN is replicated to some routers, is provided to avoid the triangular routing problem incurred by the protocol of mobile IP. In QoS provisioning, we enable the end-to-end QoS guarantee by using the resource reservation protocol (RSVP) signaling. In particular, the RSVP aggregation technique is used to avoid the scalability problem. Also, the technique of passive resource reservation is used to reduce the influence of host mobility on the resource reservation delay. We emphasize the integration of mobility and QoS management in the architecture design. A performance analysis is given to justify the benefits of our proposed architecture.     

QoS routing based on multi-class nodes for mobile ad hoc networks

In this paper, we present a new quality of service (QoS) routing protocol for mobile ad hoc networks (MANETs). Most of the existing routing protocols assume homogeneous nodes in MANETs, i.e., all nodes have the same communication capabilities and characteristics. However, in many ad hoc networks, nodes are not the same. Some nodes have longer transmission range, larger transmission bandwidth, and are more reliable and robust than other nodes. We take advantage of the non-homogeneous property to design more efficient QoS routing protocol. And node location information is used to aid routing. We also develop a new algorithm to calculate end-to-end bandwidth for a given path. Our QoS routing protocol contains end-to-end bandwidth calculation and bandwidth reservation. QoS route is discovered and setup only when it is needed. Extensive simulation studies demonstrate the good performance of the QoS routing protocol.     

A flexible and distributed architecture for adaptive end-to-end QoS provisioning in next-generation networks

A novel distributed end-to-end quality-of-service (QoS) provisioning architecture based on the concept of decoupling the end-to-end QoS provisioning from the service provisioning at routers in the differentiated service (DiffServ) network is proposed. The main objective of this architecture is to enhance the QoS granularity and flexibility offered in the DiffServ network model and improve both the network resource utilization and user benefits. The proposed architecture consists of a new endpoint admission control referred to as explicit endpoint admission control at the user side, the service vector which allows a data flow to choose different services at different routers along its data path, and a packet marking architecture and algorithm at the router side. The achievable performance of the proposed approach is studied, and the corresponding results demonstrate that the proposed mechanism can have better service differentiation capability and lower request dropping probability than the integrated service over DiffServ schemes. Furthermore, it is shown that it preserves a friendly networking environment for conventional transmission control protocol flows and maintains the simplicity feature of the DiffServ network model.     

VoIP业务QoS性能及其优化研究

简要介绍了VoIP传输的基本原理,对影响VoIP业务QoS性能的3个主要因素(时延、抖动和丢包)进行分析,提出了利用MPLSdiffserv awareTE(流量工程)集成模型进行端到端QoS性能优化的方法。MPLSdiffserv awareTE能够感知CoS(服务等级),并根据CoS细粒度来预留资源,在每个CoS级别提供MPLS容错机制,能够为VoIP业务提供低丢失、低延迟、低抖动以及确定的带宽服务,很好地满足服务质量要求。     

QoS management through service level agreements: a short overview

The Internet protocol (IP) was created as a connectionless network layer protocol that takes no attempt to distinguish between various application types. Hence, the integration of a wide range of telecommunication services over the Internet is the main reason behind the need for the provision of quality of service (QoS) guarantees to end users. In such multiservice networks, resources are managed based on service level agreements (SLA), acknowledging different types of traffic in terms of bandwidth requirements, delay and other QoS parameters. An SLA is the documented result of a negotiation between a customer and a service provider that defines service characteristics, responsibilities and priorities of every party. An SLA may include statements about tariffing and billing, service delivery, and compensations. This paper provides a short overview of some aspects of quality of service, and identifies main issues and problems of defining and managing an SLA, based on its current standardization stage.