Internet综合业务模型和资源预留协议RSVP

简要介绍了 Ｉｎｔｅｒｎｅｔ 综合业务模型的基本组成和实现机制， 并对 Ｉｎｔｅｒｎｅｔ 综合业务模型中提出的资源预留协议 Ｒ Ｓ Ｖ Ｐ 进行了简要说明和分析。     

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     

一种低轨卫星动态模型

分析了地球自转给低轨卫星动态模型带来的影响;针对大多数文献在低轨卫星动态模型中都未考虑地球自转的不足,提出了一种将地球自转考虑在内的低轨卫星动态模型,并在此模型的基础上对地面用户越区切换进行了分析;最后对模型进行了仿真分析,对于在低轨卫星动态模型中考虑地球自转的重要性做出了说明。     

A preferential attachment gathering mobility model

In this letter we propose a mobility model using preferential attachment via objects called attractors. We introduce a new kind of mobility we call Gathering Mobility, where nodes, although independent, exhibit a collective behavior. We show that this model, called Pragma, achieves a scale-free spatial distribution in the situation of population growth.     

可在INTERNET网上承载QoS业务的综合服务模型

1 引言 综合服务模型是随着Internet业务及容量不断增加而提出的，它为开发RSVP，RTP协议、处理多媒体/多播业务提供了基本框架，同时也为路由器生产厂商研制开发处理可变负荷的技术提供指南。综合服务模型的前身是D.clark，S.shenker，Lzhang在SIGCOMM92年会上提出的“Supporting Real-time Applicatlons in an Integrated Services Packet Network：Architecture and Mechanisms”。经过几年的发展，综合服务模型已经开始影响路由器及INTERNET的设计，并将在以后的几年中产生更深远的影响。     

基于互联网模式的绿色汽车美容服务技术研究

我国的经济在改革开放以来逐渐朝着多元化的方向发展,人民的生活水平也得到了明显的提高,汽车也逐渐成为普遍的代步工具,汽车美容行业也就在这种社会发展状态下应运而生。作为新兴产业,虽然得到了一定程度的发展,但是其发展空间和潜力还是巨大的,计算机技术的不断更新更是为其发展提供了相应助力。线上及线下多元化的服务模式为消费者提供了更加全面的服务保障。文章对此展开了分析。     

A closer look at service level metrics

Defined service level metrics that define acceptable frame relay network performance are increasingly offered and requested. The work of the Frame Relay Forum in providing a common vocabulary to describe frame relay service delivery is examined in this article. Copyright © 1999 John Wiley & Sons, Ltd.     

CGAM: A community and geography aware mobility model

The advances of localization‐enabled technologies have led to huge volumes of large‐scale human mobility data collected from Call Data Records (CDR), Global Positioning System (GPS) tracking systems, and Location Based Social networks (LBSN). These location data that encompass mobility patterns could generate an important value for building accurate and realistic mobility models and hence important value for fields of application including context‐aware advertising, city‐wide sensing applications, urban planning, and more. In this paper, we investigate the underlying spatio‐temporal and structural properties for human mobility patterns, and propose the Community and Geography Aware Mobility (CGAM) model, which characterizes user mobility knowledge through several properties such as home location distribution, community members' distribution, and radius of gyration. We validate the CGAM synthetic traces against real‐world GPS traces and against the traces generated by the baseline mobility model SMOOTH and assess that CGAM is accurate in predicting the performance of flooding‐based and community‐based routing protocols.     

支持无线移动因特网的IP移动性框架

主要介绍了用户的移动性给IP网络带来的挑战，给出了IP核心网的不同接入网如何实现移动性的一个设想(IP移动性框架)，详细讨论了它的4个抽象实体的功能。该结构框架确立了支持用户在基于IP核心网的不同类型接入网内的移动性所必需的移动性管理部分，能确保用户在自由漫游的时候接入Web。此外，它还可以使各种手持设备和笔记本电脑从一栋建筑物移动到另一栋建筑物，或从一个网络到另一个网络，同时能够跨越有线和无线网络。     

A new hole mobility model for hydrodynamic simulation

A new self-consistent hole mobility model that includes the lattice and the hole temperature has been proposed. By including the lattice and hole temperatures as well as the effective transverse field and the interface fixed charge, the model predicts the saturation of the hole drift velocity and shows the effects of Coulomb scattering, surface phonon scattering, and surface roughness scattering. The model has been incorporated into a device simulation program, SNU-2D. The simulation results have been compared with the reported experimental data and the measured 0.1 μm pMOSFETs, and they are shown to agree quite well. The new model is expected to estimate the characteristics of very short-channel devices in the hydrodynamic model simulations.     

A microwave model for high electron mobility transistors

In this paper, the authors present a high-frequency model for the high electron mobility transistor (HEMT). The model includes the distributed effects in the channel of the device through two newly developed wave equations in the linear and saturation regimes. The equations are solved taking into account the electric fields along and perpendicular to the flow of the current. The Y and S parameters are derived and the theoretical predictions of the model are compared with the experimental data and shown to be in good agreement over a wide range of frequencies     

A mobility model for submicrometer MOSFET device simulations

This paper describes a mobility model for submicrometer MOSFET device simulations. The model includes the quantum effects of electrons in the inversion layer proposed by Schwarz et al. By comparison with experimental data from scaled MOSFET's, the limitation of Yamaguchi's model in submicrometer device simulations is implied, while the quantum channel broadening effects have been proven significant in turn. This model can predict the current-voltage characteristics within 5- percent accuracy for scaled MOSFET's down to 0.5 µm.     

A noise model for high electron mobility transistors

A model to explain the noise properties for AlGaAs/GaAs HEMT's, AlGaAs/InGaAs/GaAs pseudomorphic HEMT's (P-HEMT's) and GaAs/AlGaAs inverted HEMT's (I-HEMT's) is presented. The model Is based on a self-consistent solution of Schrodinger and Poisson's equations. The influence of the drain-source current, frequency and device parameters on the minimum noise figure F_min and minimum noise temperature T_min, for different HEMT structures are presented. The study shows that P-HEMT's have a better noise performance than the normal and inverted HEMT's. The present model predicts that a long gate P-HEMT device will exhibit a better noise performance than a conventional HEMT. There is a range of doped epilayer thickness where minimum noise figure is a minimum for pseudomorphic HEMT's which is not observed in conventional and inverted HEMT's. The calculated noise properties are compared with experimental data and the results show excellent agreement for all devices     

打造下一代互联网业务平台

下一代互联网业务平台构想的提出 我们知道,在以IPv6为基础的下一代互联网上可以开展多种多样、千姿百态的应用与业务。天地互连公司(BII Group)从1999年开始致力于推动IPv6网络与应用在我国的部署。2001年以来,陆续在信息产业部指导下的6TNet下一代IP电信实验网以及运营商的IPv6实验网上开展了一系列IPv6应用与业务实践,包括网络视频监控、     

Internet service classes under competition

This paper analyzes competition between two Internet service providers (ISPs), either or both of which may choose to offer multiple service classes. In the model analyzed, a social planner who maximizes the total benefit from network usage and a profit maximizing monopolist will both form multiple service classes; but two networks competing to maximize profits will not. The reason is that a competition effect always outweighs a segmentation effect. Networks wish to offer multiple service classes in order to increase user benefits and hence charge higher prices. In doing so, however, they effectively increase the number of points in the service quality range at which they compete. Consequently, in any equilibrium competitive outcome, both ISPs offer a single service class. The analysis has particular implications for the Paris Metro pricing (PMP) proposal, which is considered in depth in this paper, since it suggests that PMP may not be viable under competition     

Managing service level agreements

Service level agreements are increasingly being used in enterprise networks and are contracts that specify the performance parameters within which a network service is provided. In this article their application, preparation, and effects on IT departments are considered. Copyright © 1999 John Wiley & Sons, Ltd.     

Management of service level agreements for multimedia Internetservice using a utility model

The efficient management of a quality level of Internet service is becoming increasingly important to both customers and service providers. This article describes how service level agreements for multimedia Internet service can be managed and controlled. We first present a literature survey on the problems of SLA management: SLA parameter definition, SLA measurement, and QoS management. We present a utility model to capture the management and control aspects of SLAs for multimedia Internet service. This utility model has been used in microeconomics theory, but here we have applied it to SLA management. This model provides a computationally feasible solution for admission control and quality adaptation for multimedia Internet service and SLA management. It also allows management policies to be flexibly expressed by service providers. Finally, we apply the utility model to the SLA management of VoIP service and describe how to use it for admission control, dynamic quality adaptation, and resource allocation for SLA assurance     

Evolutionary mobility and service support in DECT access networks

This paper presents an access-independent network architecture for supporting UMTS service capabilities. The approach is based on an enhanced B-ISDN core network with personal and terminal mobility provided by intelligent network techniques. A physical realization is presented, and the protocols corresponding to the physical interfaces are identified. Protocols are proposed for UMTS mobility and service support, and the impact on the B-UNI and IN interfaces is considered. Reflecting the vision of the ETSI global multimedia mobility (GMM) standardization framework, UMTS service support through non-UMTS access is considered. Consideration of DECT as a UMTS access technology leads to an interworking proposal that presents each DECT terminal to the core network in terms of UMTS functional entities. Access-independent usage of UMTS terminal applications motivates additional interworking in the terminal to encapsulate the access network. The desirability of an access-independent UMTS application programming interface in the terminal is indicated