Network of the future

Telecommunications networks of the future will exploit two new network architecture concepts that are currently being implemented, or soon will be. These are the Intelligent Network and ISDN, the Integrated Services Digital Network, which together will support a full range of voice, data, and image services that Information Age telecommunications users will demand. These new network architectures, operating synergistically with intelligence in terminal systems, will constitute a framework in which users and service providers will link together standardized functional components to create customized services. These components, along with interfaces and signaling protocols at the interfaces and within the network will result from continuing national and international standardization efforts. In the planning of these new architectures, a few major goals are of paramount importance: • the achievement of a flexible network structure in which functionality is distributed among the network components in a way which supports the timely and economic introduction of new services in response to user needs; • the establishment of industry standards at the interfaces between network elements such that service suppliers can choose among a set of available systems products in building their networks and avoid dependence on a small set of suppliers, • the development of standard user interfaces supporting signaling procedures which can provide the user with increased control of, and access to, services to satisfy his needs; Achievement of these goals will result in the realization of an Open Network Architecture. The ISDN and Intelligent Network architecture concepts are described in this paper.     

Ethernet-based public communication services: challenge and opportunity

Enterprises and residential customers increasingly take advantage of more sophisticated applications and evolve their business models. At the same time service providers face declining revenues from existing connectivity services. SPs respond to these trends and start to offer highly customized, high-bandwidth network services that complement and interwork with their existing leased line, ATM, or frame relay offerings. Ethernet is quickly becoming the customer UNI of choice. Ethernet, being a packet-based technology, complements IP-based services such as content, voice, data, video, and additional value-added services over a high-speed access connection. Ethernet also provides a flexible high-speed connection to the SP network and eliminates access bottlenecks. Using Ethernet as the common access interface, providers can employ flexible transport services that enable additional value-added services at layer 3 and above. At the same time the rollout of Ethernet services also challenges the installed base, given that bandwidth per customer is usually much higher and additional attributes for tight SLAs apply. This calls for an updated approach to network deployment and rollout: networks need to be planned and built in a service-centric fashion. Starting with a brief look at the driving forces for Ethernet-based public communication services, this article identifies five generic services for Ethernet MANs/WANs and discusses related deployment issues of the different service options, such as the degree of customization, geographic reach and bandwidth profile of the service, as well as evolution aspects of the installed base.     

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.     

Three keys to developing and integrating telecommunications servicemanagement systems

With the deregulation of the telecommunication industry in Europe and the United States, communication and information services (e.g., multimedia entertainment services, educational services) are being increasingly delivered across value chains of network, service, and value-added service providers. The benefit of such interoperable services is the provision of “one-stop shopping” in which “tailored” services are delivered without their customers dealing with the multiplicity of underlying telecommunication services and network providers. The difficulty with such delivery chains is the complexity of managing these services across the different provider organizations (i.e., across both administrative and technological domains). These difficulties include achieving an understanding of business process across the organizations and the heterogeneity of the components to be (re)used to support these business processes in the organizations. This article examines three crucial elements in ensuring successful and flexible development of such service management systems-namely, a development process which is customized to support management system component development and component reuse; the development of business models capable of representing the underlying business processes for these systems; and an integration strategy designed to assist the flexible and timely cooperation of these management components both within a single organization (single administrative domain) as well as across organizations (multidomain)     

Service convergence using MPLS multiservice networks

Enterprises are increasingly using virtual private networks to interconnect remote sites. Traditionally, service providers have used ATM core networks to deliver layer 2 services such as frame relay, ATM, or TDM private lines, which enterprise customers have then used to build their corporate network infrastructure. Such services account for the majority of data service revenues today. However, pressure has increased on service providers to combine increased flexibility with reduced costs in the context of a highly dynamic telecommunications market. Service providers also need to generate new revenues from their IP network infrastructure, through new opportunities such as IP VPNs and virtual private LAN services, while simultaneously achieving operational efficiencies through the convergence of all of their services on a common MPLS backbone. New access and metro network technologies, such as Ethernet, are also emerging that can be used to deliver these new services to enterprise customers alongside ATM and frame relay access. This must be achieved while also supporting existing technologies such as ATM, which continue to deliver highly profitable services. This article discusses the technical challenges in meeting the often conflicting requirements of delivering both traditional layer 2 services and new layer 3 services on a converged MPLS network. We show how both network and service interworking are required, and how these must operate at the user, control, and management planes to enable profitable services to be delivered over the new converged network. The different solutions being defined in the standards bodies are described, and the distinct scenarios they address are explained.     

Dynamic composition of services for end-to-end information transport - [Service-oriented broadband wireless network architecture]

An increasing number of communication technologies in access and core segments of the network belonging to different providers and subject to different network design criteria are making networks complex and difficult to manage. In such networks it is also more difficult to guarantee requested levels of quality of service. Service oriented design can be the answer to problems facing the providers of services for information transport. In this article we propose an end-to-end service composition for information transport based on principles from service oriented architecture (i.e., dynamically composing transport services with characteristics matching the requirements of a given application). SOA principles are similar to those behind the division of labor, and therefore should give providers incentive to adopt them to make better use of resources and increase revenue. As we show, some SOA concepts are similar to concepts in the open systems interconnection reference model, with the key advantages of dynamism and flexibility. We discuss service oriented networks based on transport service composition across access and core segments, and describe access network selection for online gaming. In particular, we show how semantic technologies can be used for layer 2 queries and discuss the advantages of using knowledge bases over traditional approaches.     

智能光网络的业务特征和业务构架

在光网络上直接提供宽带、优质、动态、灵活、可控的新型传送业务是智能光网络未来发展的重要方向之一。依托智能化的控制平台、综合化的管理系统，能够充分挖掘光网络的带宽潜力，直接由光域生成各类新型业务，满足多样化、个性化的用户需求。有两类业务提供构架：基于管理的业务提供方案和基于扩展业务平面的业务提供方案。基于业务平面的业务提供方案是智能光网络的重要发展方向之一。     

移动互联网对智能手机的影响

文章认为随着3G网络的部署,各种移动互联网业务的展开,网络的业务模式与运营模式发生深刻的变化,而智能手机成为这种变化的关键因素。相应地,应用安全管理框架、应用软件的安全认证机制、与其他设备之间的互联互通能力、动态电源管理等与未来智能手机技术走势密切相关,应当给予充分关注。新形式下,手机生产厂商将会逐渐向平台厂商转变,为运营商提供的是对业务的支持能力,包括硬件、协议、存储能力等,而不是具体的业务。运营商、互联网服务提供商则成为业务开发的主体。     

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     

Provision of unified IN functionality in the context of IMS

The IP Multimedia Subsystem (IMS) represents an attempt for networks convergence, allowing users of rich-content applications to communicate through any access network type. In the near future, IMS is expected to give operators and content providers the flexibility to exploit a multitude of new communication applications in a harmonized communication environment of heterogeneous IP networks. However, despite its merits, the standardization process of IMS networks is lagging behind, leaving harmonization issues of services provisioning, open. In this effort, main hindering factor is the existence of similar implementations customized per network technology. Particularly in what concerns the Intelligent Network (IN) services, these are provided in mobile networks by CAMEL (Customised Applications for Mobile networks Enhanced Logic) and in fixed networks by INAP (IN Application Part). With regard to this problem, the present work introduces a method for integrating into the context of IMS communications all types of IN logic that nowadays are available only in legacy networks. The key element of this method is a service interrogation logic, called IN-OAG (IN-Open Architecture Gateway), which can be integrated on the P-CSCF (Proxy-Call Service Control Function) component of IMS, as an enhancement for supporting IN interoperability. IN-OAG is dedicated to implementing interoperability between the core IMS and mobile, wireless or fixed networks. The functionality of the proposed architecture is shown through several example scenarios.     

Operation, administration, and maintenance of Ethernet services in wide area networks

Recent developments in Ethernet technology, such as 10G Ethernet interfaces, Ethernet passive optical networks, and resilient packet rings are pushing Ethernet from the local area network environment to metropolitan and wide area network environments. For Ethernet service providers, managing Ethernet services efficiently is key to a sustainable business model. This article discusses issues in providing OAM features and capabilities to Ethernet services over metro and wide area networks. We analyze current Ethernet features that can be leveraged in an Ethernet OAM framework, and introduce requirements and new functionalities to support Ethernet services in wide area networks.     

A policy-based management architecture for active and programmable networks

Next generation networks must be capable of supporting a multitude of service providers that exploit an environment in which services are dynamically deployed and quickly adapted over a common heterogeneous physical infrastructure, according to varying and sometimes conflicting customer requirements. In this context, network management must become more flexible in order to cope with these emerging conditions. More specifically, new management architectures must offer service providers the freedom to manage their services according to their own policies and seamlessly extend management functionality as the only way to react to the introduction of new services. Based on a new business model that describes such an environment, we propose a policy-based management architecture that is extensible and operates in an active and programmable network. This management architecture is part of a new network architecture that was developed in the FAIN European Union research and development IST project.     

Developing distributed multimedia telecommunication applications

The emerging open services market transforms services into tradable goods. It involves users; customers; service, content, and middleware providers; and network operators. This market requires effective methods to: provide new services to meet niche market demands; support customized services; provide appropriate accounting and billing mechanisms; support personal and terminal mobility, and meet information interchange security requirements such as authorization, confidentiality, and integrity. Efficient processes will reduce investment risks and let us benefit from software and hardware product development advances. To meet these needs requires an appropriate infrastructure that supports the object oriented development of distributed multimedia telecommunication applications     

On management of CATV full service networks: a European perspective

The CATV network operators hope to offer digital services and evolve their networks to full service networks. There are many hurdles for them at the moment in the transition to a digital network and digital service offering from the current analog-based technology. Key to the success of the transition will be a well-integrated and capable management system to allow CATV operators and service providers to control the network as well as the services they will offer. The CATV operators need to agree on a common data communication infrastructure and plan how their new digital services will be offered to subscribers without disrupting the current customer base of analog service users. The choice of network technology and data communication protocols will have a strong influence on the network management technology chosen. A vital element for the provision of a common open communication architecture as well as for the purposes of network management is that the IP is used. The adoption of existing standards is vital in order to establish a fast route to open network management for CATV networks. It is possible that CATV operators and service providers will have to integrate existing SNMP management systems and TMN/OSI management, with newer integrated service management systems based on TINA and implemented on a CORBA platform. There is a strong need to address security issues before any of these technologies can be deployed for service. There is currently investment (deployed systems and research) which uses each of the technologies mentioned, so these technologies will need to coexist. This article highlights the differences between the North American and European network architectures, and outlines the European network and network management scenario. This is based on the authors involvement in a Pan-European CATV project, Integrated Broadband Communication over Broadcast Networks-IBCoBN     

Session-Based Quality of Service

A primary objective of a next generation network architecture is to develop a set of infrastructure capabilities that facilitate the creation and delivery of premium services. One of these capabilities, session-based quality of service (QoS), may be used by service providers or application service providers to assure the quality of delivery of their IP content/application sessions over broadband networks.This paper introduces session-based QoS and discusses a number of considerations arising in the design of this capability for broadband services in the next few years.     

Context-Aware Migratory Services in Ad Hoc Networks

Ad hoc networks can be used not only as data carriers for mobile devices but also as providers of a new class of services specific to ubiquitous computing environments. Building services in ad hoc networks, however, is challenging due to the rapidly changing operating contexts, which often lead to situations where a node hosting a certain service becomes unsuitable for hosting the service execution any longer. We propose a novel model of service provisioning in ad hoc networks based on the concept of context- aware migratory services. Unlike a regular service that executes always on the same node, a migratory service can migrate to different nodes in the network in order to accomplish its task. The migration is triggered by changes of the operating context, and it occurs transparently to the client application. We designed and implemented a framework for developing migratory services. We built TJam, a proof-of-concept migratory service that predicts traffic jams in a given region of a highway by using only car-to-car short-range wireless communication. The experimental results obtained over an ad hoc network of personal digital assistants (PDAs) show the effectiveness of our approach in the presence of frequent disconnections. We also present simulation results that demonstrate the benefits of migratory services in large-scale networks compared to a statically centralized approach.     

The role of Internet technology in future mobile data systems

Mobile telephony and the Internet are the fastest growing businesses in the telecommunications market. This is why most operators and service providers are looking after the development of new services in both sectors, and newcomers are expected to enter the arena. The mobile operators foresee an increasing share of their revenues coming from new data services, while Internet service providers are attracted to wireless technology and mobility services both to reduce costs within the last-mile segment and to enrich their market share, providing ubiquitous access to the Internet and corporate intranets. In this scenario several wireless overlay networks will coexist, and their interworking will be a challenging objective. The employment of Internet technology, with its novel mobility and security extensions, seems to be the most attractive option for achieving that goal. In addition, the migration to a full IP network architecture, even within each specific wireless domain, will be another promising opportunity, already under consideration within several technical and standardization bodies. The envisioned role of Internet technology makes it worthwhile to undertake significant research efforts on the development of innovative IP-based mobile data systems, and opens promising opportunities for both telcos and Internet service providers.     

Dynamic Resource Allocation and Scheduling for Cloud‐Based Virtual Content Delivery Networks

This paper proposes a novel framework for virtual content delivery networks (CDNs) based on cloud computing. The proposed framework aims to provide multimedia content delivery services customized for content providers by sharing virtual machines (VMs) in the Infrastructure‐as‐a‐Service cloud, while fulfilling the service level agreement. Furthermore, it supports elastic virtual CDN services, which enables the capabilities of VMs to be scaled to encompass the dynamically changing resource demand of the aggregated virtual CDN services. For this, we provide the system architecture and relevant operations for the virtual CDNs and evaluate the performance based on a simulation.     

Cost models for QoS-differentiated interconnecting and wholesale access services in?future generation networks

Currently, network operators and Internet service providers are offering ??Triple Play?? products integrating services with different Quality of Service (QoS) requirements. It is leading to Internet traffic with strong service integration under an all-IP-based broadband network platform. However, new multimedia service offers require individual QoS guarantees for each type of services. The interconnection between different providers necessitates the reconsideration of the actual cost schemes. Interconnection and wholesale access services (It is an extension of ??wholesale network?? definition, where Telco??s physical network and equipment are ??shared?? to many independent Service Providers. If the incumbent offers broadband access services, the rest of the alternative providers have recourse to the incumbent??s ??wholesale access service??. Bitstream service is the most important service of this type, actually regulated over DSL and cable networks.) appear to be a simple solution, but the consideration of QoS parameters requires an extension of the current network dimensioning methods based mainly on the average bandwidth demand from each user. This paper proposes a cost model which considers QoS parameters and, based on the ??Total Element based Long Run Incremental Cost?? (TELRIC) model, is applied to the wholesale access and interconnection paradigm. Three traffic engineering methods are considered and studied for network dimensioning. Hereby the aim is to guarantee the QoS of the different services: complete traffic segregation under virtual tunnels, complete traffic integration by over-engineering and partial traffic integration using a priority queuing scheme. The proposed method enables the development of a specific cost scheme based on a complete scenario considering different types of users. The variety of used IP applications suppose direct implications over different levels of interconnection, mainly at the low-level Metro access and the high-level edge node.     

The Phoenix framework: a practical architecture for programmablenetworks

Programmable networks allow third parties to dynamically reprogram switches and routers in order to extend their functionality. This approach facilitates new capabilities such as dynamic reallocation of resources, automated healing from malfunctions and failures, customized information processing, and easier service creation. These capabilities enable rapid customization of the network by providing mechanisms to adapt to new applications such as multimedia, multicast, intrusion detection, and intranet firewalls. We describe Intel's framework for programmable networks, known as Phoenix. The objective of the Phoenix framework is to make it easier to deploy new network services that leverage the emerging trend toward use of reprogrammable network processors. To accomplish this goal the Phoenix framework defines an extensible mobile agent system and a set of device functionality abstractions for utilizing and extending network capabilities. We also discuss how the open interfaces provided by the Phoenix framework can be utilized to deploy new network services