移动IP中的多播技术

本文结合距离向量多播路由技术(DVMRP)介绍了移动IP下的多播技术,指出其存在的问题,并给出了一个解决方案。     

移动IP中的多播技术

本文结合距离向量多播路由技术（ＤＶＭＲＰ）多播路由技术介绍了移动ＩＰ下的多播技术，指出其存在的问题，并给出了一个解决方案。     

基于移动IP的组播协议

总结了目前在移动IP网络中组播领域的主要算法,分析比较了它们的特点和性能,概括了其中的主要研究问题,并对该领域未来的研究进行了展望.     

3G移动网络中的组播与广播

手机电视业务可以使用户在移动终端上观看电视节目。目前的手机电视都是以点到点(PtoP)的方式通过流媒体技术来实现的。但是,随着手机电视业务市场的不断拓展,简单的点到点方式已经无法满足需求,因此移动网络需要具有点到多点(PtoM)实现方式的广播,组播能力。本文简单介绍了3GPP和3GPP2中定义的新移动广播,组播业务,详细说明了其网络架构和具体的无线承载方式。     

移动IP中的多播实现机制

本文首先介绍了移动IP技术的基本原理,并在此基础上给出了移动IP中实现多播机制的四种网络模型,并分别分析了其工作原理及优缺点。最后指出了移动IP中实现多播存在的问题并对其研究前景阐述了自己的观点。     

卫星网络的IP组播问题

本介绍了目前可能用于卫星网络的IP组播协议，以及在卫星网络中使用这些协议时需要解决的问题，并对它们进行了分析和讨论。     

移动IP组播方案

目前的移动IP方案没有较好解决对组播的支持。文中分析了当前移动IP组播的几种方案以及存在的问题，比较了各自的优缺点，提出了一种改进的基于移动IP的移动主机组播技术方案，并与其他方案做了比较。     

Low-Interference Service Management Approach for Mobile Networks

Admission control and QoS adaptation are the basics of service management in mobile networks characterized by limited resources and bandwidth fluctuation. The link bit rate was the only factor considered by most of research efforts to control admission and to adapt mobile services. Moreover, most of adaptation proposals did not account for interference, which represents a important limiting issue of network performance. This paper proposes a new approach of admission control and service adaptation that takes into account, not only both bandwidth and loss rate requirements, but also user mobility with the objective of maximizing the number of admitted services while limiting signalling overhead and interference to neighbour cells. The simulation of a third generation mobile network has allowed the comparison of other schemes with the proposed approach. The latter outperformed the proposals of equal priority, guard channel capacity and request-based reservation with respect to the number of admitted services. Moreover, our service degradation and enhancement scheme further improved the admission probability, when compared to the rate-based borrowing approach, in indoor and outdoor environments.     

采用组播技术实现Mobile IP功能

详细介绍了Internet中的组播技术和Mobile IP技术，认为它们是两种关系比较特殊的技术。提出在现有的条件下，可以采用组播技术来实现MobileIP功能，具体介绍了一种采用PIM－SM来实现基本的MobileIP功能，切换和路由优化的方案，并分析了其性能。     

Multicast Flow Aggregation in IP over Optical Networks

It is widely believed that IP over optical networks will be a major component of the next generation Internet However, it is not efficient to map a single multicast IP flow into one light-tree, since the bandwidth of an IP flow required is usually much less than that of a light-tree. In this paper, we study the problem of multicast flow aggregation (MFA) in the IP over optical two-layered networks under the overlay model, which can be defined as follows: given a set of head ends (i.e. optical multicasting sources), each of which can provide a set of contents (i.e. multicast IP flows) with different required transmission bandwidth, and a set of requested content at the access routers (i.e. optical multicasting destinations), find a set of light-trees as well as the optimal aggregation of multicast IP flows in each light-tree. We model MFA by a tri-partite graph with multiple criteria and show that the problem is NP-complete. Optimal solutions are designed by exploiting MFA to formulate an integer linear programming (ILP), with two parameters: the multicast receiving index alpha and the redundant transmitting index beta. We also propose a heuristic algorithm. Finally, we compare the performance of MFA for different combination of alpha and beta via experiments and show our heuristic algorithm is effective for large-scale network in numerical results     

Multicast Routing in Mobile Ad Hoc Networks

We focus on one critical issue in mobile ad hoc networks that is multicast routing. Advantages and limitations of existing routing protocols are illustrated. Optimal routes, stable links, power conservation, loop freedom, and reduced channel overhead are the main features to be addressed in a more efficient mechanism. In this paper, we propose a new on-demand multicast routing protocol, named Source Routing-based Multicast Protocol (SRMP). Our proposition addresses two important issues in solving routing problems: (i) path availability concept, and (ii) higher battery life paths. SRMP applies a source routing mechanism, and constructs a mesh to connect group members. It provides stable paths based on links' availability according to future prediction of links' states, and higher battery life paths. This protocol succeeded to minimize network load via designing optimal routes that guarantee reliable transmission and active adaptability. A performance comparison study with On-demand Multicast Routing Protocol (ODMRP) and Adaptive Demand-driven Multicast Routing (ADMR) protocol is undertaken. Analysis results show the strength of the SRMP nodes' selection criteria and its efficient energy consumption compared to the other two protocols.     

VPN网络的移动IP技术研究

基于IPSec的VPN通过隧道技术,使得用户能够在公用网络上安全地传输私有数据。文章旨在提出一种在IPSecVPN网络中应用移动IP进行通信的构想,重点对移动节点、移动代理的要求以及相关协议流程进行了讨论。     

一种基于MobiCast的移动IP组播方案

本文提出一种改进的MobiCast方案来实现移动IP组播通信,主要解决MobiCast方案中进行区域间切换时组播数据包丢失问题。与MobiCast方案相比,在区域外地代理(DomainForeignAgent,DFA)处引入一种缓存的机制。当移动节点发生区域间切换时,移动节点的旧区域外地代理采用隧道技术,将移动节点的信息和缓存的组播数据包发送给移动节点的新区域外地代理处,减少移动节点进行区域间切换时丢失的组播数据包。     

Integrated Mobility Management Methods for Mobile IP and SIP in IP based Wireless Data Networks

With developments in voice over IP (VoIP), IP-based wireless data networks and their application services have received increased attention. While multimedia applications of mobile nodes are served by Session Initiation Protocol (SIP) as a signaling protocol, the mobility of mobile nodes may be supported via Mobile IP protocol. For a mobile node that uses both Mobile IP and SIP, there is a severe redundant registration overhead because the mobile node has to make location registration separately to a home agent for Mobile IP and to a home registrar for SIP, respectively. Therefore, we propose two new schemes that integrate mobility management functionality in Mobile IP and SIP. We show performance comparisons among the previous method, which makes separate registration for Mobile IP and SIP without integration, and our two integrated methods. Numerical results show that the proposed methods efficiently reduce the amount of signaling messages and delay time related to the idle handoff and the active handoff.     

适于低轨卫星IP网络的特定源组播算法

为了解决低轨卫星IP网络中现有特定源组播算法的信道资源浪费问题,本文提出了一套新的特定源组播算法,即基于核心群的特定源组播算法(CSSM)和加权的CSSM算法(w-CSSM).CSSM算法以源节点作为初始核心群,通过核心群和剩余组成员的最短路径方法逐步扩展直至整棵组播树构建完成,所得的树代价最小,从而大大提高了网络的带宽利用率和传输效率.在w-CSSM算法中,加权因子可以自适应调整以适度增大树代价、降低端到端传播时延,以支持某些有严格端到端时延要求的实时组播业务.通过与低轨卫星IP网络中典型特定源组播算法MRA的仿真比较,可以看出CSSM和w-CSSM算法的树代价性能比MRA有较大改善,不过端到端传播时延略高.     

IP组播密钥管理技术研究

为了在IP组播中实现用户身份认证等安全管理,避免IP组播中的不安全因素,提出了一种运用门限技术和椭圆曲线密钥体制相结合的方案,构建一个IP组播服务系统并在其上分层实现了组播密钥的分发与恢复。最后通过实验测试给出了此方案的管理代价,证明了此方案可以很好地实现IP组播应用中的密钥管理,有效地解决了用户身份认证和授权管理问题,实现了安全IP组播。     

用移动IP实现移动Ad hoc网与Internet的互联

移动IP是一种简单可扩展的全球Internet移动解决方案。本文介绍了移动IP和移动Ad hoc网络的融合技术,以实现移动Ad hoc网络与Internet的互联。     

组播业务在网络中的实施

IP组播技术实现了IP网络中点到多点的高效数据传送。由于能够有效地节约网络带宽、降低网络负载，IP组播技术在实时数据传送、多媒体会议、数据拷贝、游戏和仿真等诸多方面都拥有广泛的应用前景。但是，目前中国运营商开展组播业务的实例并不多，主要是因为在现网中实施组播技术还存在一些问题，下面就分别对这些问题进行论述。