3G移动网络中逆向GLR故障恢复算法及分析

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。     

3G中增强的3层动态位置管理建模与分析

基于3G网络中由HLR(home location register)、GLR(gateway location register)、VLR(visitor location register)构成的3层数据库结构,提出了基于移动的增强动态位置管理策略,重点分析了该策略下位置更新和寻呼的代价模型。并使用该代价模型对3G网络中基于移动的增强动态位置管理策略、基于移动的基本动态位置管理策略和静态位置管理策略进行了评价,计算结果显示增强动态位置管理策略要优于基于移动的基本位置管理策略和静态位置管理策略。     

华为HLR N＋1容灾中心解决方案

HLR(Home Location Register，家区位置寄存器)作为移动网络中最重要的数据中心，保存着用户的签约数据和位置信息，网络地位非常重要。一旦HLR发生故障，将导致严重后果：对于用户而言，将造成所有用户不能作被叫、不能进行位置更新、不能取到鉴权信息、不能接收短消息、不能修改用户自定义的补充业务；对于运营商而言，网络无法运营、营业厅及客     

基于BOSS的HLR容灾方案

归属位置寄存器(HLR)在移动通信网络中具有重要的地位,本文从网络安全及提升服务角度出发,对基于业务运营支撑系统(BOSS)的容灾备份方式进行了分析、探讨,提出低成本的解决方案.     

一种CDMA-HLR内存数据库的实现方案

针对移动通信系统中归属位置寄存器(HLR)的业务处理过程对系统的实时性和数据的安全可靠性要求,提出了一种以内存数据库作为主数据库、商用大型数据库作为备份数据库的方案,给出了系统结构和实现方式.采用该方案的HLR系统在实际使用过程中取得了很好的效果.     

移动网络中一种分布式GLR设计方案

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。     

移动通信网HLR容灾

在移动通信系统中,随着设备集成度大幅度地提高,单一节点或网元突发重大事故所造成的影响面越来越大。HLR(归属位置寄存器)作为移动网络中最重要的数据中心,保存有用户的签约数据和位置信息,地位非常重要,是移动通信系统中最重要的数据库之一。随着移动通信网的快速发展,现网中HLR的容量越来越大,     

X.25配置故障排除案例

业务运营支撑系统(BOSS,Bussiness Operation Support System)的HLR(Home Location Register,归属位置寄存器)前置机是BOSS系统修改移动电话HLR数据的惟一通道,担负着向HLR发送开／销户、停／复机、增／删各种功能指令的职责。随着移动用户的快速增长以及新业务的不断推出,HLR需要处理的工单量不断增加,以致在业务量繁忙时工单无法被及时处理,从而引起用户投诉,影响了用户满意度。     

移动网络中一种分布式GLR设计方案

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。     

移动通信系统HLR容灾技术

文章分析了移动通信系统归属位置寄存器(HLR)容灾技术,认为在移动通信系统中,HLR中的用户数据是系统运行的血脉,应通过建设容灾系统,提高HLR网元的业务可用性.文章讨论了设计容灾系统方案应考虑的各种因素:选择同步备份还是异步备份方式,选择1 1配置还是N 1配置方式,采用虚拟卷复制还是硬件复制方式,以及如何设计容灾系统的容量,并给出了具体实施时的指导原则.     

A batch‐update strategy for the distributed HLRs architecture in PCS networks

Owing to the increasing population of mobile subscribers, the rapidly expanding signaling traffic has become a challenge to the mobility management in PCS networks. Multiple database schemes to reduce signal traffic and to solve the bottleneck problem of the single home location register (HLR) architecture have been proposed by many researchers. However, in most of the multiple location databases or HLR systems, extra signaling is required for the multiple database updates. We propose a batch‐update strategy, instead of the immediate update method, for the location‐tracking schemes with replication to reduce the signaling overhead. In this paper, we first introduce a distributed HLRs architecture in which each HLR is associated with a localized set of VLRs and the location registrations and queries are processed locally. Then we propose our batch‐update strategy and present two pointing schemes for inter‐HLR call deliveries. The numerical result shows that our approach can effectively decrease the signaling cost of location registration and call delivery compared with the IS‐41 standard. Copyright © 2002 John Wiley & Sons, Ltd.     

One-step pointer forwarding strategy for location tracking indistributed HLR environment

One of the main challenges in personal communication service (PCS) is to locate many mobiles that may move frequently from place to place. Such a system operation is called location tracking. Many network signals flow, and database queries are required to achieve such a task. In addition to the two-level hierarchical strategy in IS-41 and GSM, several strategies have been proposed to improve the efficiency of location tracking. Pointer forwarding was used to reduce the expensive home location register (HLR) accesses. Previously, the distributed HLR scheme was proposed to prevent the HLR from becoming a bottleneck in the signaling network. However, the length of a forwarding pointer chain may be lengthened in a distributed HLR environment. We propose a more efficient strategy to overcome this potential problem. This strategy attempts to migrate the locating chains in a distributed HLR system when a mobile issues a registration operation. As a consequence, the length of any forwarding pointer chain does not exceed one in our strategy. Simulation results indicate that our strategy significantly decreases the locating cost. In fact, this strategy provides an upper bound of location tracking time owing to the fact that the length of any locating path does not exceed one. Furthermore, obsolete entries in local databases visitor location registers can be reclaimed in this strategy     

Dynamic hierarchical database architecture for location managementin PCS networks

This paper introduces a dynamic hierarchical database architecture for location management in personal communications service (PCS) networks. The proposed scheme allows the dynamic adjustments of user location information distribution based on the mobility and calling patterns of the mobile terminals (MTs). A unique distribution strategy is determined for each MT, and location pointers are set up at selected remote locations which indicate the current location of the MTs. This method effectively reduces the signaling and database access overhead for location registration and call delivery. Besides, the required processing is handled by a distributed network of directory registers and centralized coordination is not necessary. The functions of the other network elements, such as the home location register (HLR) and the visitor location registers (VLRs), remain primarily unchanged. This greatly facilitates the deployment of this scheme in current PCS networks     

A Virtual Private Local PCN Ring Network Based on ATM VP Cross—Connection

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Two-way calling public CT2 telepoint system

In most current implementations of CT2 telepoint systems, only handset initiated calls are allowed. This paper describes a design to allow two-way calling for the CT2 public telepoint system with minimal modifications to the current CT2 infrastructure and the public switched telephone network (PSTN). The design makes use of centralized databases in the home location register (HLR) and visitor location registers (VLR) to track the location of handsets. This location information is stored in the VLR and HLR, and is used by the PSTN to route incoming calls destined for CT2 handsets to the appropriate CT2 telepoint base station (TBS). The TBS connect to the PSTN local exchanges (LE) through the integrated services digital network (ISDN) basic rate interfaces (BRI) for fast out-of-band signaling. We present simulation results of the system with the objective of determining where congestion might occur within the system and to understand the impact of the new implementation on the PSTN. The results indicate that the performance of the system will be limited by the VLR processing speed and the number of ISDN BRI's connecting the ISDN front end (IFE) to the PSTN     

Two-level pointer forwarding strategy for location management in PCS networks

For a IPCS network to effectively deliver services to its mobile users, it must have an efficient way to keep track of the mobile users. The location management fulfills this task through location registration and paging. To reduce the signaling traffic, many schemes such as a local anchor (LA) scheme, per-user caching scheme and pointer forwarding scheme have been proposed in the past. In this paper, we present a new location management scheme which intends to mitigate the signaling traffic as well as reduce the tracking delay in the PCS systems. In this strategy, we choose a set of visitor location registers (VLRs) traversed by users as the mobility agents (MA), which form another level of management in order to make some registration signaling traffic localized. The idea is as follows: instead of always updating to the home location register (HLR), which would become the bottleneck otherwise, many location updates are carried out in the mobility agents. Thus, the two-level pointer forwarding scheme is designed to reduce the signaling traffic: pointers can be set up between VLRs as the traditional pointer forwarding scheme and can also be set up between MAs. The numerical results show that this strategy can significantly reduce the network signaling traffic for users with low CMR without increasing much of the call setup delay.     

带门槛的环形搜索移动性管理策略中移动台所 越过的位置区环数

位置管理或移动性管理是移动计算研究领域的一个具有挑战性的问题.我国及其他国家目前正在使用的个人通信网络如GSM、IS-41中,用两层数据库HLR/VLR支持位置管理.在这些网络中,每当移动台从一个位置区LA(Location area)移动到另一个位置区,其基本的位置管理策略(简称"基本策略")不管是否必要均立即进行位置更新操作,因而造成系统资源的极大浪费,降低了系统的性能.本文给出一种带门槛的环形搜索策略(简称"门槛环形策略")——将位置区分成环,设定一个门槛(整数),当移动台越过的位置区的环数没有达到门槛时,系统不进行位置更新操作,以减少位置管理的费用.在假定移动台的呼入是一个泊松过程,移动台在各个位置区的逗留时间是符合一般概率分布的随机变量的条件下,推导出在两次呼入之间移动台处于各位置区环的概率及移动台所越过的位置区环数公式,给出了"门槛环形策略"的位置管理费用小于"基本策略"的条件.