主动运维 打击网络风暴侵袭

网络风暴概念之广播风暴 造成网络风暴的原因有很多,我们拿用户工作中最常见的网络风暴一种——广播风暴来举例,一个数据帧或包被传输到本地网段（由广播域定义）上的每个节点就是广播;由于网络拓扑的设计和连接问题,或其他原因导致广播在网段内大量复制,传播数据帧,导致网络性能下降,甚至网络瘫痪。这就是广播风暴。     

如何避免IP网络中环路引起的广播风暴

IP网络中最致命的威胁就是广播风暴,广播风暴会产生很多莫名其妙的现象让人无法判断,更严重的会引起全网的瘫痪,造成重大网络事故.引起广播风暴的原因有很多,这里只讨论链路与设备引起的广播风暴.     

广播风暴的预防与排除

结合互联网维护工作中广播风暴故障的实际案例,即互联网+医疗急救、互联网+远程教育、互联网+金融保险三个领域的组网、维护以及实际网络多发的典型的广播风暴故障案例,进行故障原因及危害性分析,提出广播风暴故障的预防和排除措施,为确保互联网安全高速运行奠定基础。     

局域网广播风暴的产生及预防

本文针对某炼钢厂工业控制网络，通过网络分析，优化了网络结构，并详细分析了局域网广播风暴的产生原因，相应的防范措施及方案，详细阐述了广播风暴的产生，以及防止网络风暴所采取的措施，其中包括Vlan的划分和三层交换机的应用。     

卫星地球站播出网管系统广播风暴的产生及应对措施

随着各省卫星地球站网络化的发展,网管系统逐渐成为整个播出系统的重要组成部分,而广播风暴是导致网管系统故障的重要原因之一,从实际工作中观察播出网管系统的广播风暴是如何产生的,并思考如何应对它。     

PVLAN技术在校园网中的应用初探

随着互联网的发展,校园信息化进程不断深入,随之而来的网络安全问题也日益彰显。网络黑客利用广播风暴进行攻击的案例越来越多,传统的VLAN技术可以有效地隔离广播域,限制广播风暴的泛滥,但由于网络资源的限制,VLAN技术面临很多局限性。因此,有必要在校园网中引入PVLAN技术,通过PVLAN进一步细分VLAN划分和流量控制,为广大师生提供一个安全、稳定、高效的教学办公环境。     

EPON＋LAN环路风暴的预防

EPON逐渐成为许多广电运营商迈向全业务运营的理想接入方案,但EPON在实际运营中会遇到许多的问题,针对温岭广电EPON网络在运维中最常遇到的故障——EPON＋LAN环路所引起的广播风暴问题,分析了该类广播风暴的形成机理、原因,并提出了相应的预防措施。     

涟水广电县乡IP承载网建设方案

1 IP承载网建设方案1.1涟水县县—乡环网示意图(见图1)1.2承载网拓扑示意图(见图2)1.3承载网建设说明环形网络的设计是考虑光纤资源问题,保证乡镇之间两两相邻连接。因为是环形拓扑的设计,所以需要考虑环路带来的一些隐患,例如广播风暴。避免环路产生的广播风暴,一个有效地解决方法就是使用STP(生成树协议)。     

MANET中一种新的广播风暴抑制算法

为了解决简单的洪泛式广播所引起的广播风暴问题,提出了一种新的抑制算法。算法将结点的传输覆盖范围分成三个区域,对于不同区域内的广播消息采用不同的转发机制。仿真结果显示该算法在转发路由请求报文数、端到端延迟时间和数据吞吐量等方面要优于其他各种广播算法。     

EPON中的组播控制及其在IPTV中的应用

EPON组播技术的出现使得向一组目的地址传送数据成为可能，极大地提高了网络的传送效率，节省了网络的带宽及服务器资源，又避免了广播方式所容易产生的广播风暴问题。     

A Street Broadcast Reduction Scheme (SBR) to Mitigate the Broadcast Storm Problem in VANETs

In urban vehicular wireless environments, several vehicles can send warning messages and so every vehicle within the transmission range will receive the broadcast transmission, possibly rebroadcasting these messages to other vehicles. This increases the number of vehicles receiving the traffic warning messages. Hence, redundancy, contention, and packet collisions due to simultaneous forwarding (usually known as the broadcast storm problem), can occur. In the past, several approaches have been proposed to solve the broadcast storm problem in wireless networks such as Mobile ad hoc Networks MANETs. In this paper, we present Street Broadcast Reduction SBR, a novel scheme that mitigates the broadcast storm problem in VANETs. SBR also reduces the warning message notification time and increases the number of vehicles that are informed about the alert.     

Broadcasting safety information in vehicular networks: issues and approaches

A primary goal of intelligent transportation systems is to improve road safety. The ability of vehicles to communicate is a promising way to alleviate traffic accidents by reducing the response time associated with human reaction to nearby drivers. Vehicle mobility patterns caused by varying traffic dynamics and travel behavior lead to considerable complexity in the efficiency and reliability of vehicular communication networks. This causes two major routing issues: the broadcast storm problem and the network disconnection problem. In this article we review broadcast communication in vehicular communication networks and mechanisms to alleviate the broadcast storm problem. Moreover, we introduce vehicular safety applications, discuss network design considerations, and characterize broadcast protocols in vehicular networks.     

对软交换内部IP网络广播风暴的分析

按照中国移动通信集团公司统一部署,2004年省际层面建成全IP架构软交换汇接网,2005年开始在2G本地网层面推广引入TDM承载的软交换设备。为了尽量减少TDM资源投入、简化网络结构,2006年开始推动2G软交换IP承载语音,至今,已经基本上完成了2G软交换的语音IP承载。软交换架构无论是否已完成语音IP化改造,都含有内部IP网络,如果内部网络结构不合理就有可能发生广播风暴,产生各种各样的问题。因此,对软交换内部的IP网络进行研究,对广播风暴进行分析,可以加强维护工程师对网络结构的理解,提高对设备的维护能力,避免故障产生后对公司产生经济损失,对客户产生不良影响。     

A Framework For Handling Local Broadcast Storm Using Probabilistic Data Aggregation In VANET

Data aggregation is used to combine correlated data items from different vehicles before redistributing to other vehicles in the vehicular ad hoc networks (VANET). The number of retransmissions and the communication overhead can be reduced considerably by using aggregation. It is a prerequisite for applications that require periodic dissemination of information into a large region so that, drivers can be informed well in advance and can take alternative route in case of traffic congestion. Dissemination of information to vehicles through broadcasting creates a broadcast storm problem in VANET. In this paper a novel framework is proposed for handling the local broadcast storm problem using probabilistic data aggregation which reduces the bandwidth consumption and hence improves the information dissemination. This system exploits the knowledge base and stores the decisions for aggregation and is based on a flexible and extensible set of criteria. These criteria’s can be application specific and can enable a dynamic fragmentation of the road according to the various application requirements. The framework is evaluated for VANET based traffic information system through simulation for strictly limited bandwidth and local broadcast problem. The results demonstrate that completely structure-free probabilistic data aggregation reduces the bandwidth consumption by eliminating the local broadcast problem.     

A Water-Wave Broadcast Scheme for Emergency Messages in VANET

Vehicular Ad Hoc Network (VANET) is an emerging new technology and a promising platform for the intelligent transportation system. The most important application of VANET is disseminating emergency messages to drivers in case of dangerous events. The effectiveness depends on the design of a broadcast scheme. A simple broadcast scheme encounters many problems such as broadcast storm, connection hole, building shadow, and intersection problems. In this paper, we propose an efficient broadcast scheme that simulates water wave propagation to spread emergency messages. This scheme provides warning services with both space and time constraints. Most existing broadcast schemes provide inadequate strategies for limiting the time period of a warning. We verified the performance of our proposed scheme in a simulated street environment with vehicle movements to show the superiority of this scheme in high broadcast coverage areas.     

Performance analysis of an extended grid based broadcast algorithm in mobile ad-hoc networks

Wireless Networks - In this paper we proposed a new extended grid-based broadcasting algorithm (EGBB) in mobile ad-hoc networks (MANETs) which reduces considerably the broadcast storm problem. EGBB...     

A new method for layer 2 loop prevention in software defined networks

Telecommunication Systems - Broadcast storm refers to the bandwidth saturation caused by broadcast traffic flows when a loop exists and it can quickly lead to the network failure. In legacy...     

在VANETs城市场景下的基于自适应时延的Geocast路由协议

基于广播式的Geocast路由协议能够在特定的地理区域内高效地发布数据。然而,广播模式引起冗余重播,易导致广播风暴问题。另外,由于城市场景下建筑物的影响,现有的多数广播抑制方案难以应用于城市环境。为此,提出面向城市的基于自适应时延的Geocast路由协议UGAD(Urban Geocast based on Adaptive Delay)。UGAD采用了基于自适应时延的广播抑制方案,降低发生广播风暴的概率。同时,考虑到交叉路口的地理优势,给位于交叉路口的车辆 “优惠”的时延,使其具有优先转发数据包权力,从而提高数据包到达率。此外,考虑到城市道路的复杂性,UAGD采用基于交叉路口转发IF(Intersection forwarding)和贪婪转发GF(Greedy forwarding)两个模式,依据不同的道路情况选择不同的转发模式,从而降低冗余重播,并保持高的数据包到达率。最后,针对城市场景进行仿真,结果表明提出的UGAD具有高的数据包到达率,低的数据包重播率。