Evolving intelligent interexchange network-an SS7 perspective

The role of common channel signaling, referred to as Signaling System No.7 (SS7), in the evolution of services in an interexchange carrier environment is discussed. The importance of SS7 in evolving the intelligent network necessary to support these services is addressed. Interworking with virtual private networks via the out-of-band ISDN messaging channel (D-channel) to extend the capabilities of SS7 network signaling to customer networks is also discussed. For ubiquitous support of ISDN, CLASS, and future services, the interworking of interexchange SS7 with domestic local exchange carriers as well as foreign administrations is critical. This service and intelligent network evolution is described. Emphasis is placed on services and the anticipated migration to those types of services which demand an intelligent interaction and close coupling of both virtual private networks and local public switched networks to the interexchange network     

Signaling System No.7, IS-41 and cellular telephony networking

Globally, the common channel Signaling System No.7 (SS7) has grown and matured over the past five years in two directions. Outside of the US, the development of CCITT Signaling System No.7 (C7) has grown largely due to the need for modern call completion capabilities in national telephone networks. Within the US, SS7 has evolved from the need to provide fast and reliable database services to the support of the custom calling features to the local exchange carrier (LEC) networks. The 1990s will further accelerate the requirements for network solutions to customer needs, especially in the rapidly growing cellular telephony industry. These network solutions are forcing the merger of call delivery and database services in both the SS7 and C7 worlds. The issues, concerns, and difficulties with the merger of these functions are discussed     

七号信令网MTP3层安全机制分析

七号信令网络由于缺乏安全机制而存在诸多安全漏洞。通过分析攻击者如何利用MTP3层的网络管理消息对七号信令网实施攻击,提出用密钥交换协议和认证头协议对MTP3层进行安全保护,从而实现了信令节点间的相互认证和对消息的完整性保护,增强了七号信令网络的安全性。     

Interworking Solutions for a Two-Level Integrated Services Local Area Network

A new generation of integrated services local networks (ISLN's) is needed to yield to local area users the provision of voice, data, and images in a cost-effective manner. Besides high-speed and service integration features, these advanced multiservice communication systems have to also provide powerful interconnection with both public networks and traditional LAN's. So conception and design of the interconnection units, i.e., gateways and bridges, have to be carried out contextually with the network architecture definition. The paper addresses the interworking solutions adopted for a local integrated optical network (LION) currently under development. The architecture of bridges and gateways allowing users belonging to different LION subnetworks to communicate with public networks and commercial systems is also described. In particular, the interconnection with the integrated services digital network (ISDN) is highlighted.     

一种大型医院层次化安全信息网络的设计

本文将系统地论述如何对信息网络进行层次化设计以提高大型医院信息网络的安全性、可靠性。作者对所在单位信息网络交换模式进行了层次化设计,将医院信息网络划分为核心交换层、业务交换层;对医院内外网交互也进行了层次化设计,将网络分为内网交换层、外网交换层以及互联网服务层。同时辅以虚拟化、堡垒机、综合日志审计等一系列安全措施共同构建起坚固的全方位的安全屏障,希望能作为类似机构安全设计的参考。     

Isolating faulty routing tables in SS7 networks: present and future

The author presents the standardized method used to isolate faulty routing tables in SS7 packet switched networks, and suggests an alternative for the future. The present method used has a drawback: the extra load it induces on the network. Furthermore, it requires the audit logic, with its associated software packages, in all the SS7 nodes. The alternative suggested by this article does not induce any extra load on the network. It does not require any special audit logic in the SS7 nodes. However, it requires a TMN infrastructure. There is no doubt that TMN will gradually become a reality. But before TMN products are available on a large scale, SS7 network operators will have to do with the existing method. Routing tables can be audited using the existing method, but extra care is needed in order to avoid overloading the network. Audits therefore have to be done with circumspection. They need to be carefully scheduled, especially when used to test periodically and thoroughly all the routing tables of an SS7 network     

Reliability and performance evaluation of four tree multistage interconnection network

Reliability and performance of a multiprocessor system depend heavily upon the design of its interconnection network. This paper presents a comprehensive treatment to analyse a four tree network, a new class of irregular multistage interconnection networks (MIN), for reliability and performance. The results obtained are compared with the augmented shuffle exchange network (ASEN), a network with low link and switch complexity and having significantly improved reliability and performance amongst the regular type of MINs. The reliability results, both optimistic and pessimistic, are better than for the ASEN as well as for most of the other networks. The performance analysis in the circuit switched environment shows that the probability of accepting the requests is significantly improved and there is negligible degradation in performance with increasing network size.     

PON与OBS网络互连结构的研究

光突发交换(OBS)网络的城域网应用需要解决与接入网的互连问题。针对基于集成节点的PON与OBS网络互连方案,研究了集成节点的功能与组成结构,分析了模块之间的信息交互,给出了集成节点结构的一种设计方案,并简单讨论了基于这一方案的汇聚机制和动态带宽分配算法。     

IPv6网络OSPFv3路由协议的研究与仿真

OSPFv3是建设IPv6校园网应用最广泛的IGP之一。为促进IPv6校园网的建设,本文研究了OSPFv3路由协议的路由算法、协议的组成、分组类型和建立近邻关系的基本操作,简要分析了OSPFv3路由协议的总体框架设计和主要模块的功能,及新的功能特性,使用虚拟软件GNS3结合思科路由器IOS开展OSPFv3组网仿真实验,分别实现AS的主区域互联、多区域互联和虚连接的典型场景。     

虚拟化云交换中心的探索与实践

文章介绍了云交换中心(CXP,Cloud Exchange Point)业务需求,探讨我国新型互联网交换中心部署多云交换场景的可行性,并具体介绍了虚拟化云交换中心的设计思路和测试实践,使企业能够实时开通上云或多云互联业务,基于高速通道让网络时延优化近30%,让企业上云更容易、更快、更稳定。     

Multiple Linear Regression Application on the Inter-Network Settlement of Internet

1Introduction Thequestiondiscussedinthispaperishowtosettle amongIBP.Theinternetindustryisdynamic.The numberofInternetServiceProviders(ISP)isincreasing rapidlyandthestructureoftheindustrychangecontinu ously[1].Telecommunicationsindustryhasalwaysfocusedthe …     

七号信令网中基于MTP3层的安全机制研究

七号信令系统作为电信网络的神经系统,其安全问题日益严重.给出了SS7网络面临的主要安全威胁,分析了攻击者利用网络缺乏认证机制,通过MTP3层的网络管理消息对七号信令网实施攻击.提出用密钥交换协议和认证头协议对MTP3层进行安全保护,增强SS7网络的安全性.     

基于自路由互连网络的粗粒度可重构阵列结构

互连网络在粗粒度可重构结构(Coarse-Grained Reconfigurable Array, CGRA)中非常重要,对CGRA的性能、面积和功耗均有较大影响。为了减小互连网络导致的面积开销和功耗并提升CGRA的性能,该文提出一种具有自路由和无阻塞特性的互连网络,构建了一种层次型的网络拓扑结构。通过这种互连网络,任意一对处理单元之间均可以建立连接和交换数据,而且这种连接是自路由和无阻塞的。实验结果显示,与已有结构相比,该结构以至多增加14.1%的面积开销为代价,获得最高可达46.2%的整体性能提升。     

Mesh-connected rings topology for network-on-chip

With the feature size of semiconductor technology reducing and intellectual property （IP） cores increasing, on-chip interconnection network architectures have a great influence on the performance and area of system-on-chip （SoC） design. Focusing on trade-off performance, cost and implementation, a regular network-on-chip （NoC） architecture which is mesh-connected rings （MCR） interconnection network is proposed. The topology of MCR is simple, planar and scalable in architecture, which combines mesh with ring. A detailed theoretical analysis for MCR and mesh is given, and a simulation analysis based on the virtual channel router with wormhole switching is also presented. The results compared with the general mesh architecture show that MCR has better performance, especially in local traffics and low loads, and lower cost.     

用于不变特征抽取的MADALINE网络的改进和硬件实现

从实时应用的角度计论和改进了ＭＡＤＡＬＩＮＥ神经网络，给出了局部连接型ＭＡＤＡＬＩＮＥ不变网络的算法结构，将算法简化为一般的矩阵运算，提出了通过学习确定固定ＭＡＴ阈值和自适应ＭＡＪ阈值的方法，用硬件实现了处理二值输入模式的局部连接型ＭＡＤＡＬＩＮＥ网络，给出了ＭＡＤＡＬＩＮＥ网络原型与改进型的比较结果。     

国内电话网中No.1与No.7信令方式的配合

本文以市话接续和长途接续为例,讨论了国内No.1与No.7信令方式中电话用户部分(IUP)的信号配合,特别是国内电话网多频记发器(MFC)信号与No.7信令方式的信号配合,以及前向信号和后向信号的转换关系。     

Signaling System No.7 in corporate networks

Corporate network user requirements are identified. The significance of Signaling System No.7 (SS7), in corporate network as a separate backbone signaling system for implementing a robust, flexible and transparent communication network is discussed. The architecture for a corporate network utilizing enhanced signaling is described. The use of SS7 instead of the integrated services digital network primary rate interface (ISDN PRI) is explored. Some SS7 applications in corporate networks are examined     

七号信令系统的安全性设计

在Internet和电信网络攻击事件日益频繁的情况下,由于七号信令(SS7)协议是完全公开的,SS7的各层消息也是完全透明的,因而需要考虑信令网的安全性设计问题。介绍了SS7底层的安全脆弱性,提出基于消息传递单元(MSU),采用类似于Internet中IKE与IPSec的信令密钥交换及信令安全封装协议,以解决SS7的安全性问题。     

An architecture for residential Internet telephony service

A new architecture that can be used for offering an Internet telephony service to residential customers is introduced. The architecture addresses scalability and availability requirements of mass-market deployment of carrier-grade services and supports interconnection with SS7 for Internet telephony calls to the public switched telephone network. The architecture is based on the concept of a gateway decomposition that separates the media transformation function of today's H.323 gateways from the gateway control function of the gateways and centralizes the intelligence in a call agent. The media gateway control protocol is introduced as the protocol between the call agent that assumes the gateway control function and the gateway that provides just the media transformation function. Interworking between the architecture and the public switched telephone network, the session initiation protocol, and H.323 are also discussed