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1.
移动用户全球漫游的日益普遍导致了网络间信令传输的急剧增加.为了优化漫游用户位置管理过程中网络间的信令传输,GLR(Gateway Locati on Register)系统作为UMTS/ IMT-2000移动通信系统的一个可选部分被引入.本文介绍了GL R系统的概念和特征,之后引入数学模型分析了引入GLR系统后对网络间信令传输的优化率.  相似文献   

2.
移动用户全球漫游的日益普遍导致了网络间信令传输的急剧增加.为了优化漫游用户位置管理过程中网络间的信令传输,GLR(Gateway Locati on Register)系统作为UMTS/ IMT-2000移动通信系统的一个可选部分被引入.本文介绍了GL R系统的概念和特征,之后引入数学模型分析了引入GLR系统后对网络间信令传输的优化率.  相似文献   

3.
基于IMS(IP Multimedia Subsystem)域的通信中由于切换层次的增多导致切换时间的增加,从而使得服务的中断时间加长,这影响了移动中应用的服务质量.在UMTS(Universal Mobile Telecommunication System)R6规范中的切换流程中,跨网络切换采用SGSN(Serving GPRS Support Node)之间的切换而GGSN(Gateway GPRS Support Node)不变,这会导致数据流在IP(Internet Protocol)网络中的迂回,并且多条信令跨网络传输影响了切换的速度,增加了网络流量和端到端延时.该文在现有切换流程上提出了跨GGSN的切换流程,缩短了媒体流在切换过程中的中断时间,并减少了漫游状态下的端到端媒体流引起的网络流量和端到端的数据延迟.  相似文献   

4.
3GPP在UMTS R5中提出IMS作为下一代网络(NGN)技术在移动通信中的实现,但IMS业务触发机制的缺陷给交互管理带来挑战.把IMS中业务特征冲突分为SCFI(Single Component Fea-ture Interaction)和MCFI(Multi-component Feature Interaction)两类,利用SIP协议的可扩展性携带业务触发信息,提出解决MCFI类业务冲突的算法及方案.此方案为3GPP Service Broker标准制定提供了参考.  相似文献   

5.
SIP协议是由IETF提出的IP电话信令协议,它用于建立、修改和终结多个用户终端之间的多媒体会话。第三代无线系统(3G)的R5结构中,IP多媒体子系统域(IMS)选择SIP作为终端和IMS以及IMS内部各元素之间的信令协议。本文针对SIP协议在IMS中的应用展开介绍,重点介绍了IMS中由SIP协议实现的业务注册和会话建立流程。  相似文献   

6.
第三代移动通信系统是能提供多种类型IP数据业务的通信系统.会话起始协议SIP是3G的IP多媒体子系统中提供多媒体业务的核心技术.文章首先介绍了SIP的基本工作原理,然后对3GPP UMTS R5定义的IMS进行了简要描述,最后详细阐述了SIP在IMS提供服务的过程及对漫游用户的处理.  相似文献   

7.
UMTS核心网在访问网络处引入可选网元GLR来减少用户远离HLR漫游时的位置管理信令开销.传统GLR方案中,GLR一般在访问网络处集中设置,随着访问网络处漫游用户数的增多,GLR有可能成为系统瓶颈,且GLR的故障对系统是致命的.针对集中式GLR存在的问题,该文提出一种分布式GLR设置方案,使用户在访问网络处的首个访问VLR成为其GLR,从而提高系统对GLR故障的抗毁性,有效降低GLR潜在的瓶颈问题.分析结果表明,该文提出的分布式GLR方案在抗毁性,缓解瓶颈问题,降低入呼数据库查询开销及延迟等指标方面都优于传统GLR方案,同时,所提出的分布式GLR方案易于实现,只需相关网元软件升级即可.  相似文献   

8.
朗讯基于IMS的下一代网络   总被引:2,自引:0,他引:2  
鲍敢峰 《电信科学》2004,20(11):77-79
1 IMS标准 3GPP是制订WCDMA标准的国际标准化组织,至今推出了R99(又称R3)、R4和R5三个标准版本.这几个版本都存在网络结构方面的变化.R4在核心网电路域引入了软交换,实现了控制与承载分离.R5在分组域增加了IP多媒体子系统(IP multimedia subsystem,IMS),提出了全IP的网络架构.IMS采用SIP(会话初始协议)进行控制,实现移动性管理、多媒体会话信令和载体业务传输,实现端到端的IP业务.正在定义中的3GPP R6版本,在网络架构方面已没有太大的变更,主要是增加了一些新的功能特性,以及对已有功能特性的增强.3GPP2将与3GPP协调工作,以达成双方IMS标准的一致.  相似文献   

9.
3G移动网络中逆向GLR故障恢复算法及分析   总被引:1,自引:0,他引:1  
在3G网络中,当漫游用户在网关位置寄存器(GLR)中的位置信息不正确时,其位置查询将失败,此时将严重恶化系统性能,而传统的位置恢复算法需占用大量长途电路资源.为减少GLR位置恢复过程中对长途电路资源的占有及缩短GLR故障恢复时延,本文提出了一种新的算法-逆向GLR故障恢复算法.该算法充分利用用户在访问位置寄存器(VLR)中的用户信息,从而避免在恢复过程中GLR和归属位置寄存器(HLR)的长途信令开销.通过对算法的性能作分析,证明所提出的算法是可行的.  相似文献   

10.
IP多媒体子系统自从3GPP UMTS Release5后已经被加入到通用移动通信系统(UMTS)的核心网络中.现在,UMTS网络主要包含以下3个域:电路交换(CS)、分组交换(PS)和IP多媒体子系统(IMS).IMS需要同原有相对陈旧的网络电路交换(CS)网络及公用电话交换网(PSTN).本文主要针对IMS同PSTN/CS网络的互通进行了概述.  相似文献   

11.
无差别移动性管理网络   总被引:2,自引:0,他引:2  
为了使IMS网络提供更加灵活的移动性支持,提出了一种无差别移动性管理网络。这种网络可以提供良好的服务移动性和用户移动性,使得用户可以永远以本地用户的身份使用接入地的服务,并对在此网络结构下的用户位置管理和会话建立进行了分析。实验结果表明,这种网络结构可以很好地支持用户移动性和服务的移动性。并且在此网络结构下的会话建立开销和用户位置注册开销,均比IMS目前采用的归属地控制方式下的用户注册开销和会话建立开销要小。  相似文献   

12.
In personal communications applications, users communicate via wireless with a wireline network. The wireline network tracks the current location of the user, and can therefore route messages to a user regardless of the user's location. In addition to its impact on signaling within the wireline network, mobility tracking requires the expenditure of wireless resources as well, including the power consumption of the portable units carried by the users and the radio bandwidth used for registration and paging. Ideally, the mobility tracking scheme used for each user should depend on the user's call and mobility pattern, so the standard approach, in which all cells in a registration area are paged when a call arrives, may be wasteful of wireless resources. In order to conserve these resources, the network must have the capability to page selectively within a registration area, and the user must announce his or her location more frequently. We propose and analyze a simple model that captures this additional flexibility. Dynamic programming is used to determine an optimal announcing strategy for each user. Numerical results for a simple one-dimensional mobility model show that the optimal scheme may provide significant savings when compared to the standard approach even when the latter is optimized by suitably choosing the registration area size on a per-user basis. Ongoing research includes computing numerical results for more complicated mobility models and determining how existing system designs might be modified to incorporate our approach  相似文献   

13.
Mobile IP is a simple and scalable global mobility solution. However, it may cause excessive signaling traffic and long signaling delay. Mobile IP regional registration is proposed to reduce the number of location updates to the home network and to reduce the signaling delay. This paper introduces a novel distributed and dynamic regional location management for Mobile IP where the signaling burden is evenly distributed and the regional network boundary is dynamically adjusted according to the up-to-date mobility and traffic load for each terminal. In our distributed system, each user has its own optimized system configuration which results in the minimal signaling traffic. In order to determine the signaling cost function, a new discrete analytical model is developed which captures the mobility and packet arrival pattern of a mobile terminal. This model does not impose any restrictions on the shape and the geographic location of subnets in the Internet. Given the average total location update and packet delivery cost, an iterative algorithm is then used to determine the optimal regional network size. Analytical results show that our distributed dynamic scheme outperforms the IETF Mobile IP regional registration scheme for various scenarios in terms of reducing the overall signaling cost.  相似文献   

14.
陆斌 《通信学报》2007,28(3):125-129
在3G蜂窝网络中,归属位置寄存器(HLR)、网关位置寄存器(GLR)、访问位置寄存器(VLR)组成三级数据库结构。当漫游移动用户在GLR中的位置信息错误或过时时,对该用户的入呼将失败。由于三层结构设计中,GLR与HLR的通信一般涉及国际长途信令,使得GLR的故障恢复设计非常重要。为尽可能减少对长途资源的占有,对GLR故障恢复提出了一种新的算法并对其性能作了相应的分析。  相似文献   

15.
文章探讨并提供了一种简单高效的国际漫游网络优选解决方案。在该解决方案中,归属网络运营商用户可以在漫游地自动注册到拥有高优先级的网络,归属网络运营商可以控制这一过程,从而实现其对国际漫游用户的可管可控。该方案基于现网的HLR网元来实现,无需部署新网元,投资少,见效快,对现有网络基本上没有影响,值得运营商实验、部署。  相似文献   

16.
In this letter, an integrated location information management strategy is proposed for mobile networks, where local anchor and replica are deployed to efficiently manage the location information of a mobile terminal (MT) based on its call and mobility characteristics. As an MT's user is roaming within the local signal transfer point (LSTP) region serving the user's home or workplace, the MT's location change is reported to a local anchor (LA)-the visitor location register (VLR) associated with the user's home or workplace. Meanwhile, the LA's location is replicated at several switches (called the replicas) originating relatively high call rates to the MT. As a result, the MT's home location register (HLR) needs to be accessed only when the MT changes its LSTP region or an incoming call for the MT is generated by a nonreplica originating switch. This is shown to reduce location tracking costs.  相似文献   

17.
A profile-based location strategy and its performance   总被引:5,自引:0,他引:5  
Future microcellular personal communications systems (PCSs) will be characterized by high user density and high mobility. It is expected that registrations will incur a large amount of the radio link signaling traffic. A profile-based strategy (PBS) is proposed to reduce the signaling traffic on the radio link by increasing the intelligence within the fixed network. The system maintains a sequential list of the most likely places where each user is located. The list is ranked from the most to the least likely place where a user is found. When a call arrives for a mobile, it is paged sequentially in each location within the list. When a user moves between location areas in this list, no location update is required. The list may be provided by the user or may be based on each user's past calling history. The method for doing this is outside the scope of this work. This work focuses on the potential performance improvements that can result from maintaining such a list. This paper compares the performance of the proposed strategy to the typical geographic-based location-tracking schemes being implemented in evolving digital cellular and cordless standards. Key performance measures for the comparison are radio bandwidth, fixed network SS7 traffic, and call setup delay. We investigate the conditions under which the PBS performs better than the traditional scheme. Results indicate that over a wide range of parameters, it may be possible to reduce both the radio bandwidth and fixed network signaling load for a modest increase in call setup delay  相似文献   

18.
This paper proposes an authentication technique for use in the global mobility network (GLOMONET), which provides a personal communication user with global roaming service. This technique is based on new distributed security management, where authentication management in roaming-service provision is conducted only by the roamed network (the visited network). The original security manager (OSM) administrates the original authentication key (OAK) acquired when a user makes contracts with the home network, while the temporary security manager (TSM) is generated for a roamer in the visited network in order to provide roaming services. The TSM generates and administrates the temporary authentication key (TAK) for a roamer, which key is confidential to the OSM, releases the TAK administration when a roamer moves to other networks, and then disappears. The proposed authentication technique consists of two phases. In the roaming-service-setup phase, triggered by the user's location registration request, authentication control to set up the roaming-service environment is negotiated by the TSM in the visited network, the OSM, and the roamer. In the roaming-service-provision phase, triggered by the user's service request, authentication control to provide the roaming service is negotiated (using the TAK acquired by the roamer in the first phase) only by the visited network and the roamer. This authentication control using the TAK provides a unified authentication procedure with a single logic to both subscribers and roamers. In addition, the security management of the whole GLOMONET is reinforced and the security responsibility is made clear by allocating the subscriber's/roamer's security administration to only the TSM  相似文献   

19.
Location tracking with distributed HLR's and pointer forwarding   总被引:11,自引:0,他引:11  
Location tracking operations in a personal communications service (PCS) network are expensive. A location tracking algorithm called pointer forwarding has been proposed to reduce the location update cost. The key observation behind forwarding is that if users change PCS registration areas (RAs) frequently, but receive calls relatively infrequently, it should be possible to avoid registrations at the home-location register (HLR) database by simply setting up a forwarding pointer from the previous visitor-location register (VLR). Calls to a given user will first query the user's HLR to determine the first VLR, which the user was registered at, and then follow a chain of forwarding pointers to the user's current VLR. To reduce the “find” cost in call delivery, the PCS provider may distribute HLR databases in the network. This paper integrates the concept of distributed HLRs with pointer forwarding, and the new scheme is referred to as the pointer forwarding with distributed HLR (PFDHLR). Since no registration to the HLR is performed in the pointer forwarding scheme when a user moves to the new locations, the cost of updating multiple HLRs is eliminated in PFDHLR. Our study indicates that PFDHLR may significantly reduce the mobility management cost compared with the single HLR approach  相似文献   

20.
An important issue in location management for dealing with user mobility in wireless networks is to reduce the cost associated with location updates and searches. The former operation occurs when a mobile user moves to a new location registration area and the network is being informed of the mobile user's current location; the latter operation occurs when there is a call for the mobile user and the network must deliver the call to the mobile user. In this paper, we propose and analyze a class of new agent-based forwarding schemes with the objective to reduce the location management cost in mobile wireless networks. We develop analytical models to compare the performance of the proposed schemes with existing location management schemes to demonstrate their feasibility and also to reveal conditions under which our proposed schemes are superior to existing ones. Our proposed schemes are particularly suitable for mobile networks with switches which can cover a large number of location registration areas.  相似文献   

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