用蛀洞路由技术构造的分布式并行计算机系统

采用路由技术是新型多计算机并行系统的重要特征,本文介绍蛀洞路由技术的特点及其在构造分布式并行计算机系统中的应用,并给出了用蛀洞路由器C104构造的“长缨-Ⅲ分布式并行仿真计算机系统”的结构实例。     

“曙光1000”并行机讲座 第二讲 “曙光1000”并行机程序设计

“曙光１０００”并行机讲座第二讲“曙光１０００”并行机程序设计黄晓东中国成都高性能计算中心四川成都（６１００３１）１曙光１０００编程环境曙光１０００的编程工具主要是以“串行语言＋并行库”的形式提供的。目前支持的语言有Ｃ、Ｃ＋＋和ＦＯＲＴＲＡＮ等等，支...     

蛀洞路由器C104及其在多计算机系统中的应用

采用蛀洞路由机制是新型多计算机系统的重要特征。介绍了多计算机系统中蛀洞路由机制的基本概念。     

“曙光1000”并行机讲座 第一讲 “曙光1000”和中国成都高性能计算中心

经国家科委批准，中国成都高性能计算中心于１９９７年１１月１１日在西南交通大学举行隆重的建成挂牌仪式，国务院信息办、国家科委、国家教委、铁道部、电子部、中科院和省、市领导到会祝贺。省、市新闻单位对此作了及时的报道。为了充分利用中心的并行计算机资源，为全国，特别是我国西部地区的用户服务，本刊特开辟高性能计算机讲座，介绍“曙光１０００”的系统结构、性能和应用。讲座共三讲，本期刊出第一讲，除简介“曙光１０００”外，着重介绍如何申请国家高性能计算基金来使用“曙光１０００”为科研服务。下一讲的题目是：“曙光１０００”并行计算机编程环境。     

创新才能赢——曙光2000-Ⅰ超级服务器体系结构和设计思想解析

曙光2000-Ⅰ是国家智能计算机研究开发中心研制的可扩展超级服务器系统,它以曙光天演工作站为计算节点机,节点 CPU 采用 Motorola 公司的300MHz PowerPC 604e,节点之间通过10/100Mbps 高速以太网和100MBps 的蛀洞路由芯片组成二维网络互连。系统可配置4到128个计算节点,一个控制台节点。在32个计算节点省缺配置下,整机峰值速度达到200GFLOPS(即每秒200亿次综合运算)。1月12日,在“曙光2000-1超级服务器暨’98新成果汇报会”上,曙光信息产业有限公司总工程师徐志伟介绍了该机的设计思想和体系结构。徐总介绍说,曙光采用了可扩展机群体系结构,实现了单一系统映象。简单地讲,可扩展机群体系结构是指将一组节点计算机通过高性能互     

用蛀洞路由器ST_C104构造全互连多机并行系统

采用蛀洞路由机制是新型多计算机并行系统的重要特征,介绍用蛀洞路由器ＳＴ＿Ｃ１０４构造全互连多机并行系统的方法并给出构造实例,证明它具有并行效率高、通信速度快、拓扑结构可变、扩展性强等特点。     

曙光1000大规模并行计算机系统软件的设计

曙光１０００是基于消息的大规模并行计算机系统。本文介绍曙光１０００系统软件的设计目标，重要的微核心，用户空间服务。客户／服务模型和标准用户界面的设计思想，实现技术路线，以及组织结构，并详细阐述了系统诊断与监控，系统管理，并行程序开发环境与工具和调试器的设计。     

月度新闻

4月16日“I”芯曙光突破极限4月16日,国内服务器领导厂商曙光公司联合国际芯片巨头Intel在北京新世纪日航酒店举行高端战略合作推介会,曙光展示了基于Intel高性能芯片的全线曙光Ⅰ系列服务器产品。同时,还与媒体共同分享了曙光与Intel的战略规划蓝图——即曙光将针对高端市场重磅打造Intel四路新至强以及新安腾产品。曙光是最早发布和推广双核产品的服务器厂家,拥有最完整的服务器产品线,并长期与Intel保持着稳定、良好的合作关系。     

曙光推出第一台完全自主的基于龙芯的防火墙

2007年8月7日，曙光公司举行了主题为“中国芯，更安全”的产品发布会，推出首款基于国产龙芯处理器的网络安全产品——曙光100L防火墙。该产品采用龙芯2E处理器。曙光自主开发主板，结合曙光自主的防火墙软件。形成了软硬件一体化的防火墙安全系统。该产品实现了从硬件到软件、从系统到芯片的完全自主知识产权，可以预见，基于龙芯处理器的防火墙将对中国网络安全的发展产生深远影响。     

曙光二代刀片以平衡取胜

4月26日,以“机群系统的整合与发展”为核心设计思想的曙光第二代64位刀片服务器TC1600上市。背板标准由曙光自行设计开发,据称是真正的无源背板,可以实现Intel芯片与AMD芯片的混插。据曙光技术支持中心总经理邵宗有介绍,TC1600最高可支持20颗Intel64位Nocona/Irwindale/Paxville DP(双核)处理器,而曙光将在今年年底推出基于AMD芯片的双路单核刀片服务器,并计划于2007年3月推出AMD双路双核刀片服务器,2007年5月推出AMD四路刀片服务器。一向推崇集群服务器的曙光,为何一反打压刀片服务器的态度,在此时大力推出多款刀片服务器产品?…     

虫洞路由芯片的伸缩缓冲区设计与实现

虫洞路由交换机制由于延迟时间短,对路由芯片缓冲区容量要求小等特点,被广泛应用在机群交换网络的路由芯片中。但阻塞时占用整个传送路径,会使网络吞吐率下降,此外,刹车问题的存在,会限制数据传送速率。该文提出了用伸缩缓冲区技术解决虫洞路由芯片刹车问题的方法,并已在DawningUX8路由芯片中实现,应用结果表明既可以很好地解决刹车问题,也可以提高网络性能。     

曙光5000高性能计算机Barrier网络的设计

为优化Barrier操作的性能,提高大规模并行计算应用在曙光5000系统中的执行效率,文中提出了一种基于硬件的Barrier加速设计.该设计是采用树形Barrier算法,通过增强曙光5000互联网络交换芯片的功能,实现低延迟、可扩展、高可靠和可管理的Barrier网络.该网络支持并发16个Barrier操作,可在Fat-Tree拓扑环境下实现较低的Barrier操作延迟.相比已有实现,是更适合Fat-Tree拓扑的设计方案.理想情况下,1024个节点的同步操作在1.7μs内完成.根据Barrier操作归约和分发过程的特点,分别采用请求应答和超时催促两种机制,为Barrier操作的可靠性提供保障.以该设计实现的Barrier网络原型系统已通过FPGA验证.     

DAWA: Defending against wormhole attack in MANETs by using fuzzy logic and artificial immune system

Mobile ad hoc networks (MANETs) are mobile networks, which are automatically outspread on a geographically limited region, without requiring any preexisting infrastructure. Mostly, nodes are both self-governed and self-organized without requiring a central monitoring. Because of their distributed characteristic, MANETs are vulnerable to a particular routing misbehavior, called wormhole attack. In wormhole attack, one attacker node tunnels packet from its position to the other attacker nodes. Such wormhole attack results in a fake route with fewer hop count. If source node selects this fictitious route, attacker nodes have the options of delivering the packets or dropping them. For this reason, this paper proposes an improvement over AODV routing protocol to design a wormhole-immune routing protocol. The proposed protocol called defending against wormhole attack (DAWA) employs fuzzy logic system and artificial immune system to defend against wormhole attacks. DAWA is evaluated through extensive simulations in the NS-2 environment. The results show that DAWA outperforms other existing solutions in terms of false negative ratio, false positive ratio, detection ratio, packet delivery ratio, packets loss ratio and packets drop ratio.     

A necessary and sufficient condition for deadlock-free routing incut-through and store-and-forward networks

This paper develops the theoretical background for the design of deadlock-free adaptive routing algorithms for virtual cut-through and store-and-forward switching. This theory is valid for networks using either central buffers or edge buffers. Some basic definitions and three theorems are proposed, developing conditions to verify that an adaptive algorithm is deadlock-free, even when there are cyclic dependencies between routing resources. Moreover, we propose a necessary and sufficient condition for deadlock-free routing. Also, a design methodology is proposed. It supplies fully adaptive, minimal and non-minimal routing algorithms, guaranteeing that they are deadlock-free. The theory proposed in this paper extends the necessary and sufficient condition for wormhole switching previously proposed by us. The resulting routing algorithms are more flexible than the ones for wormhole switching. Also, the design methodology is much easier to apply because it automatically supplies deadlock-free routing algorithms     

A framework for designing deadlock-free wormhole routing algorithms

This paper presents a framework to design fully-adaptive, deadlock-free wormhole algorithms for a variety of network topologies. The main theoretical contributions are: (a) design of new wormhole algorithms using store-and-forward algorithms, (b) a sufficient condition for deadlock free routing by the wormhole algorithms so designed, and (c) a sufficient condition for deadlock free routing by these wormhole algorithms with centralized flit buffers shared among multiple channels. To illustrate the theory, several wormhole algorithms based on store-and-forward hop schemes are designed. The hop-based wormhole algorithms can be applied to a variety of networks including torus, mesh, de Brujin, and a class of Cayley networks, with the best known bounds on virtual channels for minimal routing on the last two classes of networks. An analysis of the resource requirements and performances of a proposed algorithm, called negative-hop algorithm, with some of the previously proposed algorithms for torus and mesh networks is presented     

Universal wormhole routing

We examine the wormhole routing problem in terms of the “congestion” c and “dilation” d for a set of packet paths. We show, with mild restrictions, that there is a simple randomized algorithm for routing any set of P packets in O(cdη+dη log P) time with high probability, where L is the number of flits in a packet, and η=min {d, L}; only a constant number of flits are stored in each queue at any time. Using this result, we show that a fat tree network of area ⊖(A) can simulate wormhole routing on any network of comparable area with O(log³ A) slowdown, when all worms have the same length. Variable length worms are also considered. We run some simulations on the fat tree which show that not only does wormhole routing tend to perform better than the more heavily studied store and forward routing in this context, but that performance superior to our provable bound is attainable in practice     

A theory of deadlock-free adaptive multicast routing in wormholenetworks

A theory for the design of deadlock-free adaptive routing algorithms for wormhole networks, proposed by the author (1991, 1993), supplies sufficient conditions for an adaptive routing algorithm to be deadlock-free, even when there are cyclic dependencies between channels. Also, two design methodologies were proposed. Multicast communication refers to the delivery of the same message from one source node to an arbitrary number of destination nodes. A tree-like routing scheme is not suitable for hardware-supported multicast in wormhole networks because it produces many headers for each message, drastically increasing the probability of a message being blocked. A path-based multicast routing model was proposed by Lin and Ni (1991) for multicomputers with 2D-mesh and hypercube topologies. In this model, messages are not replicated at intermediate nodes. This paper develops the theoretical background for the design of deadlock-free adaptive multicast routing algorithms. This theory is valid for wormhole networks using the path-based routing model. It is also valid when messages with a single destination and multiple destinations are mixed together. The new channel dependencies produced by messages with several destinations are studied. Also, two theorems are proposed, developing conditions to verify that an adaptive multicast routing algorithm is deadlock-free, even when there are cyclic dependencies between channels. As an example, the multicast routing algorithms of Lin and Ni are extended, so that they can take advantage of the alternative paths offered by the network     

A survey of wormhole routing techniques in direct networks

Several research contributions and commercial ventures related to wormhole routing, a switching technique used in direct networks, are discussed. The properties of direct networks are reviewed, and the operation and characteristics of wormhole routing are discussed in detail. By its nature, wormhole routing is particularly susceptible to deadlock situations, in which two or more packets may block one another indefinitely. Several approaches to deadlock-free. routing, along with a technique that allows multiple virtual channels to share the same physical channel, are described. In addition, several open issues related to wormhole routing are discussed     

双工k-ary n-mesh的虫孔路由分析

现代多处理机系统的互联网络多采用虫孔路由流控制。该文针对虫孔路由流控制和确定性路由算法下的双工ｋ－ａｒｙ ｎ－ｍｅｓｈ计算机互联网,采用倒推算法建立了求解消息平均传输延迟的分析模型,并建立仿真模型,理论分析与仿真结果基本吻合,表明该分析模型具有较好的精确度。     

虚网叠加构造自适应路由算法的有效框架

大规模并行处理机系统中路由算法对互联网络通信性能和系统性起着重要作用。