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是谁最早提出的大象流定义

按照《软件定义安全：SDN/NFV新型网络的安全揭秘》中第8页所述：由于openflow交换机流表数目的限制，SDN控制器程序难以在大规模的网络环境中静态部署全部的表项。如果采用动态部署的方式，则流表与交换机之间的通信性能直接受到交换机控制层面CPU能力的监制：一方面，带宽指标难以达到数据平面的量级，另一方面，延迟也会受到控制器性能和控制网络状态的影响。DevoFlow（见Ref）的工作从数据中心流量特性的角度出发，针对性地对网络流量进行优化。在实际数据中心网络中，导致网络拥塞的流量可能指只占10%，而这些流量占总流量大小的90%，被称为大象流（Elephant Flow），其余流量被称为老鼠流（Mice Flow）。DeveFlow通过定期的采样统计流量，检测大象流并对其进行标记，之后集中对这些流量采用动态负载均衡，多路径等流量工程技术进行优化。Ref：Curtis R A, Mogul C J,Tourrilhes J, et al. DevoFlow: Scaling Flow Management for High-Performance Networks, ACM SIGGCOM Computer Communication Review, 2011, 41(4): 254-265
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Theubiquitous heavy-tailed distributions in the Internet implies an interestingfeature of the Internet traffic: most (e.g. 80%) of the traffic is actuallycarried by only a small number of connections (elephants), while the remaininglarge amount of connections are very small in size or lifetime (mice). In afair network environment, short connections expect relatively fast service thanlong connections. However, some- times we cannot observe such nice property inthe current Internet.2001年ICNP会议的一篇《The War Between Mice and Elephants》Introduction部分给出了定义。Aninteresting feature of the flows shown in Figure 1 is a very large number ofvery short flows, and a few very long flows. The terminology "mice andelephants" provides a useful metaphor for understanding thischaracteristic of internet traffic: there are relatively few elephants, and alarge number of mice. Another way of thinking of mice and elephants is that thedistribution of lengths of the flows is heavy tailed. 2002年，《Mice and elephants visualization ofinternet traffic》这篇论文进一步说明了大象和老鼠只是一种比喻。Bulkdata transfer, also called elephant flows, that are large volume and relativelylong lasting flows usually generated by data backup, virtual machine migration,etc., and short-lived data exchange, also called mice flows, e.g.,transactional traffic, web browsing, search queries. Elephant flows that arerequiring large bandwidth but without strict temporal constraints, account forapproximately 80% of total traffic in DCNs. In contrast, short-lived mice flowsare often very sensitive to latency and have deadline constraint eventuallydefined by a Service Level Agreement (SLA) between cloud provider and customer.Because of the latency requirements, applications generating mice flows have asignificant impact on the users’ perceived experience. This requires specifictreatment for mice flows, like assigning higher priorities than elephant flowsto them.2016年，IEEETransactions on network and service management的一篇论文《Adaptive Path Isolation for Elephant andMice Flows by Exploiting Path Diversity in Datacenters》针对大象流和老鼠流给出了具体的例子。
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谱图理论里出现过大象流(不知道有没有打错字)


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