以太网业务的带宽轮廓

以太网业务中一个比较重要的属性就是带宽轮廓属性.根据带宽轮廓用户可以按需购买带宽,而供应商则可以根据带宽的使用情况来收费并且为在带宽轮廓内的业务帧提供性能保证,供应商还可以根据带宽轮廓来更加有效地规划网络资源.通过带宽轮廓,业务供应商在每个UNI上可以提供多种业务同时每种业务都具有它们自己的带宽轮廓.对带宽轮廓参数、带宽轮廓算法以及带宽轮廓的业务属性进行了论述.     

An economic model for pricing tiered network services

We consider networks offering tiered services and corresponding price structures, a model that has become prevalent in practice. We develop an economic model for such networks and make contributions in two important areas. First, we formulate the problem of selecting the service tiers from three perspectives: one that considers the users’ interests only, one that considers only the service provider’s interests, and one that considers both simultaneously, i.e., the interests of society as a whole. We also present an approximate yet accurate and efficient solution approach for tackling these nonlinear programming problems. Given the set of (near-) optimal service tiers, we then employ game-theoretic techniques to find an optimal price for each service tier that strikes a balance between the conflicting objectives of users and service provider. This work provides a theoretical framework for reasoning about and pricing Internet tiered services, as well as a practical toolset for network providers to develop customized menus of service offerings. Our results also indicate that tiering solutions currently adopted by ISPs perform poorly both for the providers and society overall.     

A look at the video dial-tone network

As organisations with information to sell implement an array of multimedia services for the home, others, too, are hard at work. Telephone companies, as well as cable operators, are busy developing broadband intelligent networks to underpin those broadcast and interactive offerings. The phone companies define their network as a common-carrier transport service, in that it grants equal access to all information providers, including themselves, and enables consumers to "dial up" video or multimedia applications offered by third parties. This kind of service has become known as a video dial-tone network. The user first gets a menu from the network provider. He or she then picks an information provider, which sends its own interactive menu of services to the customer     

An agile server for cross-provider service peering and aggregation

Telecommunications and next-generation network IP-based services can be increasingly delivered at network edges and in peered third-party networks. As a result, subscribers bypass operators' services in favor of alternative novel services; accordingly, potential revenue is lost. By bundling existing viable network-based services across providers, however, service providers can create new revenues and avoid further erosion of their market share. Business announcements attest to this growing trend, but thus far cross-provider solutions take the form of point-to-point customized integrations. In the emerging service delivery paradigm, providers must be able to interwork fluidly with partners already operating profitable services, and do so without going through the risky and costly service development cycle, and without the need for extensive customized software development. We outline an intelligent-agent-based service peering and aggregation server whose deployment on service provider networks enables such interworking.     

Resource Management for Virtual Private Networks

Virtual private networks (VPNs) have rapidly emerged as a leading solution for multi-site enterprise communication needs. Provider-managed solutions modeled on RFC 2547 serve as a popular choice for layer 3 VPNs, and the hose model has emerged as a common and simple service specification. It offers a hose of a certain contracted bandwidth to customers. With the growth in size and number of VPNs and the uncertainties in the traffic patterns of customers, providers are faced with new challenges in efficient provisioning and capacity planning for these networks and satisfying customer service level agreements (SLA). We suggest that a set of techniques can be used to help the provider build an adaptively provisioned network. These techniques involve continually processing measurement information, building inferences regarding VPN characteristics, and leveraging them for adaptive resource provisioning. We developed scalable techniques to infer VPN characteristics that are important for provisioning tasks. We demonstrated the feasibility of such provisioning techniques with existing measurement obtained using SNMP infrastructure from a large IP/VPN service provider. Our examination of measurement data yielded interesting new insights into VPN structure and properties. Building on our experience with analyzing VPN characteristics, we articulate an adaptive provisioning architecture that enables providers to effectively deal with the dynamic nature of customer traffic     

Competition in Parallel-Serial Networks

We study the efficiency implications of competition among profit-maximizing service providers in communication networks. Service providers set prices for transmission of flows through their (sub)network. The central question is whether the presence of prices will help or hinder network performance. We investigate this question by considering the difference between users' willingness to pay and delay costs as the efficiency metric. Previous work has demonstrated that in networks consisting of parallel links, efficiency losses from competition are bounded. Nevertheless, parallel-link networks are special, and in most networks, traffic has to simultaneously traverse links (or subnetworks) operated by independent service providers. The simplest network topology allowing this feature is the parallel-serial structure, which we study in this paper. In contrast to existing results, we show that in the presence of serial links, the efficiency loss relative to the social optimum can be arbitrarily large. The reason for this degradation of performance is the double marginalization problem, whereby each serial provider charges high prices not taking into account the effect of this strategy on the profits of other providers along the same path. Nevertheless, when there are no delay costs without transmission (i.e., latencies at zero are equal to zero), irrespective of the number of serial and parallel providers, the efficiency of strong oligopoly equilibria can be bounded by 1/2, where strong oligopoly equilibria are equilibria in which each provider plays a strict best response and all of the traffic is transmitted. However, even with strong oligopoly equilibria, inefficiency can be arbitrarily large when the assumption of no delay costs without transmission is relaxed.     

A service level model and Internet mobility monitor

Mobility is gaining a tremendous interest among Internet users and wireless access networks are increasingly being installed to enable mobile usage. Internet mobility requires solutions to move between access networks with maintained network connectivity. Seamless mobility in turn means that the experience of using a service is unaffected while being mobile. Communication in next generation networks will use multiple access technologies, creating a heterogeneous network environment. Further, roaming between network service providers may take place. To enable mobile nodes to move between access networks within as well as between network service providers with minimal disruption, nodes should be able to maintain multiple active network connections. With the usage of multihomed nodes, seamless mobility can be achieved in already installed infrastructures, not providing mobility support. Mobility in heterogeneous access networks also requires network selections that scale for services. In this article we propose an architecture where application service providers and network service providers define service levels to be used by a mobile node and its user. The user selects a service and the service level from an application service provider. When performing access network selection, information received as part of an application service level will be used to find a network that supports the service required. The performance of available access networks will be monitored and considered when making the decision. Our proposed architecture provides solutions to move flows between interfaces in real-time based on network performance, quality of service signalling to correspondent nodes, and cancellation of flows to give way for more important traffic.     

A Nash–Stackelberg equilibrium model for internet and network service providers in the demand market—a scenario-based approach

This paper evaluates the optimal pricing for two Internet service providers and two network providers; all are competing on price, which is based on quality. To find the optimal prices of service and network providers and to determine optimal scenarios, a two-stage competition is modeled. In the first stage, network providers compete on market prices by setting the quality in four scenarios. At this stage, we found the equilibrium prices in the market. In the second stage, by obtaining market prices, service providers compete on network prices. Finally, the equilibrium solutions are compared with each other by considering the intensity of market competition in price and quality. It is shown that equilibrium never occurs in the case when the smaller service provider has a higher Internet quality than the other (scenario 2) and the more significant service provider offers a higher Internet quality (scenario 4). Besides, when both Internet service providers offer low-quality Internet (scenario 1) and high-quality Internet (scenario 3), the companies make the most profit. By increasing and decreasing the competition in quality, equilibrium would still exist for the first scenario, and the third scenario, respectively. The intensity of market competition in price behaves oppositely as quality.

     

Assessing Network Service Profitability: Modeling From Market Science Perspective

Network service providers regularly conduct network planning and upgrade processes to keep their businesses profitable. The effectiveness of a network upgrade/planning decision is intrinsically tied to the ability of a provider to retain and grow its customer population. This paper examines the crucial linkage between network performance, customer satisfaction and profitability of network service, and presents an analytical modeling approach from market science perspective. We derive a generalized forecasting model that projects service profitability from the underlying network service infrastructure and the subscriber population. Through simulation studies and analysis, we show how such approach captures key factors and trends influencing service profitability and how it can significantly improve current network planning and upgrade processes.     

Game-theoretic pricing for video streaming in mobile networks

Mobile phones are among the most popular consumer devices, and the recent developments of 3G networks and smart phones enable users to watch video programs by subscribing data plans from service providers. Due to the ubiquity of mobile phones and phone-to-phone communication technologies, data-plan subscribers can redistribute the video content to nonsubscribers. Such a redistribution mechanism is a potential competitor for the mobile service provider and is very difficult to trace given users' high mobility. The service provider has to set a reasonable price for the data plan to prevent such unauthorized redistribution behavior to protect or maximize his/her own profit. In this paper, we analyze the optimal price setting for the service provider by investigating the equilibrium between the subscribers and the secondary buyers in the content-redistribution network. We model the behavior between the subscribers and the secondary buyers as a noncooperative game and find the optimal price and quantity for both groups of users. Based on the behavior of users in the redistribution network, we investigate the evolutionarily stable ratio of mobile users who decide to subscribe to the data plan. Such an analysis can help the service provider preserve his/her profit under the threat of the redistribution networks and can improve the quality of service for end users.     

多主多从Stackelberg博弈下的边缘缓存资源分配算法

为鼓励视频服务提供商参与到缓存过程中,本文提出一种基于Stackelberg博弈的激励缓存资源分配算法。与传统激励缓存资源分配方案不同,本文考虑同时存在多个网络运营商和多个视频服务提供商,视频服务提供商从网络运营商处购买存储空间以缓存热门视频。针对该场景,本文将该激励缓存模型建模为多主多从Stackelberg博弈问题,分别构建主方和从方的效用函数,证明了在网络运营商价格确定的情况下,视频服务提供商之间的非合作博弈存在纳什均衡。文章利用分布式迭代算法对该博弈模型进行求解,获得了视频服务提供商的最优缓存策略和网络运营商的最优价格策略。仿真结果表明,本文提出的激励缓存机制可使视频服务提供商获得比其他缓存分配算法更高的单位成本收益。      

Scalability implications of virtual private networks

This article gives an overview of the most promising technologies for service providers to offer virtual private network services. The focus is on the analysis of the scalability implications of these virtual private network mechanisms on existing service provider backbone networks. Very often, when deploying VPN services, service providers will be confronted with a trade-off between scalability and security. VPNs that require site-to-site interconnectivity without strong (cryptographic) security can be deployed in a scalable way based on the network-based VPN model, as long as the interaction between the customer and provider routing dynamics are controlled. VPNs that require strong (end-to-end) cryptographic security should be deployed according to the CPE-based VPN model, using the available IPsec protocol suite     

Optimal Nonlinear Pricing for a Monopolistic Network Service Provider with Complete and Incomplete Information

In the communication network pricing literature, it is the linear pricing schemes that have been largely adopted as the means of controlling network usage or generating profits for network service providers. This paper extends the framework to nonlinear pricing and investigates optimal nonlinear pricing policy design for a monopolistic service provider. The problem is formulated as an incentive-design problem, and incentive (pricing) policies are obtained for a many-users regime, which enable the service provider to approach arbitrarily close to Pareto- optimal solutions. Under the assumption that the service provider knows the true user types, analytical and numerical results indicate a profit improvement exceeding 38% over linear pricing by the introduction of nonlinear pricing. We also consider the scenario where the service provider has incomplete information on user types. A comparative study of the results for complete information and incomplete information is carried out as well, with numerical results pointing to 25%-40% loss of profit by the service provider due to incompleteness of information on the user types.     

How to buy a network: trading of resources in the physical layer

Recently, a number of new research initiatives, most notably UCLPv2 and GENI, have promoted the dynamic partition of physical network resources (infrastructure) as the means to operate the network, and to implement new protocols and services. This has led to a number of open issues such as resource discovery, implementation of resource partitioning, and the aggregation of resources to create arbitrary network topologies. To us, the key issue is the design of a mechanism to trade, acquire, and control network resources, given a choice of providers of physical resources (infrastructure providers). In this article we present an architecture that allows physical resources to be traded, while granting users controlled access to the acquired resources via a policy enforcement mechanism. In addition, it allows resource provider domains to be linked via configurable, provider-neutral resource exchange points that are the physical resource equivalents of the pooling point, or Internet exchange point (IXP). We demonstrate how our trading system will operate by presenting a use case in which a network topology is constructed using resources from multiple providers, be it Internet service providers (ISPs), or National Research Experimental Network (NREN) providers. The use case also shows how a dynamic reconfiguration can be effected by the customer though the use of simple access control policies, without involving the provider     

Design Strategies for Meeting Unavailability Targets Using Dedicated Protection in DWDM Networks

Service providers operating dense-wavelength-division-multiplexed networks are often faced with the problem of designing their networks such that a certain level of service availability can be delivered to their customers. This paper introduces optimization-based algorithms that address this problem efficiently and effectively. For a given network topology, specified by existing dark-fiber links, our algorithms determine a cost-effective solution consisting of the size and location of equipment needed to satisfy the desired amount of point-to-point traffic demands. In addition, the solution approach discussed in this paper delivers estimates for the service unavailability probability of each traffic-demand pair and enables the service provider to programmatically determine which and how many supplemental node-disjoint protection paths are required in order to attain a prespecified demand-pair unavailability target. To the best of our knowledge, these algorithms provide the user with the most detailed design created by any optimization-based design tool to date. The efficiency and effectiveness of the proposed network-design algorithms is studied using an empirical analysis     

ARC: an integrated admission and rate control framework for competitive wireless CDMA data networks using noncooperative games

The competition among wireless data service providers brings in an option for the unsatisfied customers to switch their providers, which is called churning. The implementation of Wireless Local Number Portability (WLNP) is expected to further increase the churn rate (the probability of users switching the provider). However, the existing resource management algorithms for wireless networks fail to fully capture the far-reaching impact of this unforeseen competitiveness. From this perspective, we first formulate noncooperative games between the service providers and the users. A user's decision to leave or join a provider is based on a finite set of strategies. A service provider can also construct its game strategy set so as to maximize their utility (revenue) considering the churn rate. Based on the game theoretic framework, we propose an integrated admission and rate control (ARC) framework for CDMA-based wireless data networks. The admission control is at the session (macro) level while the rate control is at the link layer packet (micro) level. Two admission control modes are considered - one-by-one mode and batch processing mode, in which multiple users are admitted at a time. We show that: 1) for the one-by-one mode, the Nash equilibrium using pure strategy can be established for both under-loaded and fully-loaded systems and 2) for batch processing mode, there is either an equilibrium in pure strategy or a dominant strategy exists for the service provider. Therefore, the providers have clearly defined admission criteria as outcome of the game. Users are categorized into multiple classes and offered differentiated services based on the price they pay and the service degradation they can tolerate. We show that the proposed ARC framework significantly increases the provider's revenue and also successfully offers differentiated QoS to the users.     

Competitive Pricing for Spectrum Sharing in Cognitive Radio Networks: Dynamic Game, Inefficiency of Nash Equilibrium, and Collusion

We address the problem of spectrum pricing in a cognitive radio network where multiple primary service providers compete with each other to offer spectrum access opportunities to the secondary users. By using an equilibrium pricing scheme, each of the primary service providers aims to maximize its profit under quality of service (QoS) constraint for primary users. We formulate this situation as an oligopoly market consisting of a few firms and a consumer. The QoS degradation of the primary services is considered as the cost in offering spectrum access to the secondary users. For the secondary users, we adopt a utility function to obtain the demand function. With a Bertrand game model, we analyze the impacts of several system parameters such as spectrum substitutability and channel quality on the Nash equilibrium (i.e., equilibrium pricing adopted by the primary services). We present distributed algorithms to obtain the solution for this dynamic game. The stability of the proposed dynamic game algorithms in terms of convergence to the Nash equilibrium is studied. However, the Nash equilibrium is not efficient in the sense that the total profit of the primary service providers is not maximized. An optimal solution to gain the highest total profit can be obtained. A collusion can be established among the primary services so that they gain higher profit than that for the Nash equilibrium. However, since one or more of the primary service providers may deviate from the optimal solution, a punishment mechanism may be applied to the deviating primary service provider. A repeated game among primary service providers is formulated to show that the collusion can be maintained if all of the primary service providers are aware of this punishment mechanism, and therefore, properly weight their profits to be obtained in the future.     

NIRA: A New Inter-Domain Routing Architecture

In today's Internet, users can choose their local Internet service providers (ISPs), but once their packets have entered the network, they have little control over the overall routes their packets take. Giving a user the ability to choose between provider-level routes has the potential of fostering ISP competition to offer enhanced service and improving end-to-end performance and reliability. This paper presents the design and evaluation of a new Internet routing architecture (NIRA) that gives a user the ability to choose the sequence of providers his packets take. NIRA addresses a broad range of issues, including practical provider compensation, scalable route discovery, efficient route representation, fast route fail-over, and security. NIRA supports user choice without running a global link-state routing protocol. It breaks an end-to-end route into a sender part and a receiver part and uses address assignment to represent each part. A user can specify a route with only a source and a destination address, and switch routes by switching addresses. We evaluate NIRA using a combination of network measurement, simulation, and analysis. Our evaluation shows that NIRA supports user choice with low overhead.     

Component-based charging in a next-generation multimedia network

In classical networks, charging and billing are important tools for customer care to fight competition and to assure the operator's revenue. If charging is to remain a prime competitive tool in next-generation networks, it must be functionally intelligent and flexible, and able to optimize operator and service provider revenues while providing a fair policy toward the end users. Multimedia sessions can be considered as being composed of a number of call components, each of which might consist of different bearer and service objects. The NGN multimedia network structure and its business model define four players involved in charging: access provider, connection provider, telecommunication service provider, and value-added service provider. Often charging components must be correlated to create a clear postpaid bill and ensure correct treatment of prepaid accounts, as well as settlement between the providers involved.     

下一代网络演进策略探讨及其市场发展趋势

在简要介绍IMS体系架构的基础上,从固定和移动两个角度,重点讨论了以IMS为核心的下一代网络可实施的发展策略和演进步骤,并分析了下一代业务市场的发展趋势、业务潜力及运营商的对策。