银行综合柜面业务系统安全运行

当前,银行业的发展迅猛,行业间的竞争逐步白热化,业务种类和数量在迅速增加,对服务质量的要求也越来越高了。与此同时,综合柜面业务系统数据大集中后给银行带来了许多实际的效益:方便了维护,有利于数据、帐务的统一管理,减少了网间交易的中间环节,方便了资金清算,有利于银行各项业务的拓展。本文以建行山西省分行综合柜面业务系统为例分析了其运行平台的可用性。     

Secure service convergence based on scalable media coding

In multimedia services, security and privacy issues are urgent to be solved, such as the content security and service protection. To solve these issues, some means have been proposed, such as conditional access and digital rights management. However, for the latest application scenarios in convergent networks, there is still no solution. This paper focuses on the convergent multimedia broadcasting applications: the multimedia content, e.g., TV program, is encoded and packaged by the content provider, and is then transmitted to users through different communication networks, e.g., 3G network, DVB-H, ADSL, etc. Thus, the same multimedia content will be used for various services, i.e., mobile TV, Internet TV and home TV. Since different network channel support different bandwidths, the multimedia content should be transcoded before being transmitted through the networks. To protect the content and service in this application, we propose the content and service protection methods. In content protection, the content provider encrypts the scalable multimedia content with the manner denoted by Encryption Flag. The content distributor has no decryption keys, but can transcode the scalable content with the manner denoted by Layer Flag, and transmit the transcoded content to users. In service protection, the content provider combines the encryption key, Encryption Flag and the user right information, and transmits them, independent from the encrypted content, to certified users. At user side, the content is decrypted with the received key according to the Encryption Flag and Layer Flag. Thus, the content provider needs only to encrypt the content once, which can be transcoded by the content distributor in a secure manner and used for various networks. Additionally, the user rights need not to be changed when the service network is changed. Totally, the proposed scheme is secure and efficient for service convergence.     

民航干扰查处难点和对改善民航通信质量的建议

在民用航空频率专项整顿期间，石家庄民用机场反映在石家庄机场至衡水市上空（118．35MHz）机载电台受到干扰，根据省局安排，衡水分局在辛集市旧城镇至衡水市航线上进行了实地测试。     

Toward IP virtual private network quality of service: a service provider perspective

To complement classical enterprise wide area network infrastructures, IP (based) virtual private networks have been gaining ground, with the capability of offering cost-effective, secure, and private-network-like services. In order to provision the equivalent quality of service of legacy connection-oriented layer 2 virtual private networks (VPNs), IP VPNs have to overcome the intrinsically best effort characteristics of the Internet in this multimedia era. This article discusses the IP VPN quality of service (QoS) issue from a service provider point of view, where QoS guarantees are carried out at the network level as well as at the node level. It presents the whole picture by highlighting and stitching together various QoS enabling technologies from previous research and engineering work.     

Service quality in TINA: quality of service trading in open networkarchitecture

Enterprise-level QoS issues are discussed, from which QoS evolution paths are derived. Service-level QoS issues are identified, and they have been studied as a part of service quality issues in TINA service architecture. TINA stream binding and its role in the TINA QoS framework are presented. Soft guarantee of stream quality is proposed, which does not require strict resource reservation. The soft guarantee concept combined with TINA stream binding architecture supports progressive evolution of service quality     

TIP's performance quality of service

The author presents a transport performance quality of service (QoS) parameter set, which enables applications to describe their required performance properties and guarantees appropriately. The performance QoS is provided at the service interface of the Transport and Internetworking Package (TIP), which is an adaptive transport system based on an object-oriented and modular architecture     

Scalability and quality of service: a trade-off?

During the last decade, two big efforts on Internet quality of service were made. The first, IntServ, promises precise per-flow service provisioning but never really made it as a commercial end-user product, which was mainly accredited to its lack of scalability. Its successor, DiffServ, is more scalable at the cost of coarser service granularity - which may be the reason why it is not yet commercially available to end users either. This leaves us with the question: is there a fundamental trade-off between QoS and scalability? A trade-off that, in the long run, could prevent deployment of QoS for end users altogether?.     

Secure communications in local multipoint distribution service (LMDS) networks

The transmission of confidential information over LMDS networks is investigated in the present paper from an information-theoretic standpoint. The major factor impairing the link performance at these networks is rain attenuation, a physical phenomenon exhibiting both spatial and temporal variation. Based on an accurate channel modeling, analytical expressions of the probability of non-zero secrecy capacity and the outage probability for this type of networks are provided, giving for the first time an information-theoretic approach of the problem of secure transmission for LMDS networks. Useful conclusions are drawn through extended numerical results suggesting the increase of operational frequency and the use of more directional antennas to improve security in transmission of confidential messages for this type of networks.     

Provisioning for interdomain quality of service: the MESCAL approach

This article presents an architecture for supporting interdomain QoS across the multi-provider global Internet. While most research to date has focused on supporting QoS within a single administrative domain, mature solutions are not yet available for the provision of QoS across multiple domains administered by different organizations. The architecture described in this article encompasses the full set of functions required in the management (service and resource), control and data planes for the provision of end-to-end QoS-based IP connectivity services. We use the concept of QoS classes and show how these can be cascaded using service level specifications (SLSs) agreed between BGP peer domains to construct a defined end-to-end QoS. We illustrate the architecture by describing a typical operational scenario.     

An introduction to quality of service

Quality of service (QoS) is like ‘life’ — a dictionary may define the word but it does not help us understand its meaning. This paper defines what is meant by QoS in the context of packet networks. It discusses the drivers that lead to the development of QoS for IP networks in the context of the history of packet communications. The paper then presents the basic packet QoS taxonomy using the simple analogy of the postal system. It also briefly looks at potential future developments, while discussing general QoS issues throughout.     

Restorable dynamic quality of service routing

The focus of quality-of-service routing has been on the routing of a single path satisfying specified QoS constraints. Upon failure of a node or link on the path, a new path satisfying the constraints has to be established. However, resources needed to satisfy the QoS requirements are not guaranteed to be available at the rerouting instant, so QoS is not guaranteed upon failure. Restorable QoS routing, where active and backup paths must be simultaneously set up, has been previously studied. This is mostly motivated by the incorporation of mechanisms to establish QoS guaranteed paths with failure protection in multiprotocol label switching networks. This article describes some previously developed algorithms for dynamic routing of restorable QoS guaranteed paths     

Management of quality of service enabled VPNs

New emerging IP services based on differentiated services and the IP security architecture offer the level of communication support that corporate Internet applications need nowadays. However, these services add an additional degree of complexity to IP networks which will require sophisticated management support. The management of enhanced IP services for their customers is thus an emerging important task for Internet service providers. This article describes a potential management architecture service providers will need for that task, considering problems such as multiprovider services and service automation. We focus on a quality-enhanced virtual private network service which is particularly useful for corporate internetworking     

Ensuring quality of service for image transmission: hybrid loss protection

We present hybrid loss protection as a new channel coding and packetization scheme for image transmission over nonprioritized lossy packet networks. The scheme employs an interleaver-based structure, and attempts to maximize the expected peak signal-to-noise ratio (PSNR) at the receiver given the constraint that the probability of failure, i.e., the probability that the PSNR of the decoded image is below a given threshold, is upper-bounded by a user-defined value. A new code-allocation algorithm is proposed, which employs Gilbert-Elliot modeling of the network statistics. Experimental results are provided in the case of transmission of images encoded by SPIHT and JPEG 2000 over a wireline, as well as a wireless UMTS-based Internet connection.     

基于光GMPLS接入网中区分服务的QoS研究

通过配置区分服务体系实现基于光GMPLS环状网络的QoS测量,涉及到不同的实时多媒体服务.讨论并分析区分服务结构的三种服务级别的特性.仿真结果表明,在网络过载的情况下,快速转发类和保证转发类都有很好的保护作用.加速转发类适合于实时服务,而最大努力类对任何类型的服务}生能都非常低,同时保证转发非常适合于视频流.     

Loss profiles: A quality of service measure in mobile computing

With rapid technological advances being made in the area of wireless communications it is expected that, in the near future,mobile users will be able to access a wide variety of services that will be made available over future high-speed networks. The quality of these services in the high-speed network domain can be specified in terms of several QOS parameters. In this paper we identify a new QOS parameter for the mobile environment, calledloss profiles, that ensuresgraceful degradation of service (for applications that can tolerate loss) in situations where user demands exceed the network's capacity to satisfy them. A new transport sub-layer is proposed that efficiently implements this new QOS parameter. We also show how this protocol can be easily incorporated into existing proposals for high-speed network transport layer protocols and into the MPEG-2 Transport System.This work was supported by the NSF under grant number NCR-9410357.     

国外电信服务质量监管机制

我国政府及电信行业管制部门对电信服务质量的监管给予了高度重视。电信服务质量不仅是电信企业生存和参与竞争的根本,而且与广大电信消费者息息相关,涉及到电信消费者的切身利益,因此提高电信服务质量是电信企业,电信消费者和电信管制机构共同的目标和愿望。电信服务监管机制就是实现上述三者利益最大化的游戏规则,同时三方利益又相互制约,共同促成了电信服务质量的提升和发展。介绍了国外几种主要的电信服务质量监管机制,并对其利弊进行了分析,旨在为我国电信服务质量的监管提供参考。     

Real-time scheduling with quality of service constraints

Whether or not the introduction of traffic classes improves upon the performance of ATM networks is discussed within the framework provided by a class of networks that guarantees quality of service. To provide a meaningful comparison the authors define the concept of a schedulable region, a region in the space of loads for which the quality of service is guaranteed. The authors show the dependence of the schedulable region on the scheduling algorithm employed, quality of service parameters, and traffic statistics. An efficient real-time scheduling algorithm is introduced that substantially increases the schedulable region without incurring prohibitive complexity costs. The schedulable region associated with this algorithm is compared with the ones generated by the static priority scheduling algorithm and a variant of the minimum laxity threshold algorithm. The size and shape of the schedulable region is explored by means of simulations     

Digital audio broadcasting: High-grade service quality through on-board processing techniques

A digital audio broadcasting (DAB) satellite system is presented here which provides a high-grade quality of service for some hundreds of channels. This, with minimum cost of the radio set and of the broadcasting station, greatly improves the radio broadcasting service throughout the world, especially in areas where deployment of conventional relay infrastructure is difficult and not yet cost-effective. Potential broadcasters located in the visible hemisphere can directly up-link their programming to the DAB satellites. Broadcasters can also copy each up-link channel and steer flexibility to any beam or combination of satellite beams. The paper illustrates the advantages and the feasibility of a DAB system based on geostationary satellites with on-board processing generating signals of MCPC (multiple channel per carrier) type. This multiplexing technique allows large system margins. This solution allows the satellite L-band TWTA amplifiers to be operated in saturation and eliminates the intermodulation noise associated with the transmission of FDMA channels. A powerful coding scheme has been selected to create a ‘robust’ down-link. In this way several high-power DAB channels of radio programming, with selectable data rate, are directly delivered to the users.     

武器装备维修服务质量评价研究

首先介绍了服务质量评价的理论和维修服务质量评价研究,然后依据SERVQUAL,结合武器装备维修服务的过程,从顾客的角度建立了武器装备维修服务质量的评价指标体系,并通过实例进行了应用。