肯塔基大学的研究人员通过支持SDN的校园网络轻松移动大量数据。

从天文学到生物信息学到诊断医学再到物理学及其他，科学需要移动大量数据集。使这可能是科迪·鲍姆加德（Cody Bumgardner）的使命。

"Researchers need to move data that's generated on campus to the cloud and other universities," explains Bumgardner, director of research computing at University of Kentucky.

大数据扼杀了网络

在Terabytes和Petabytes中测量的移动数据对于科学合作是必不可少的，但是鲜明的现实是，传统的校园网络根本不是旨在支持普遍的大数据。

许多大学使用科学DMZ来解决这个问题。科学DMZ是该网络的一部分，该网络建于校园周边，该网络已针对高性能科学应用而不是企业计算进行了优化。研究人员的台式机，服务器和其他数据服务在科学DMZ中被隔离。面临的挑战是，安全性和其他网络政策并未持续执行。

University of Kentucky wanted to take a fresh approach: an all-campus science DMZ. "We wanted to keep the researchers' desktops and servers on the campus network," says Bumgardner.

一个跨部门团队工作。

Using SDN to Speed Big Data Flows

Using SDN is a strategic approach to deploying campus networks.
科迪·邦加德纳（Cody Bumgardner），肯塔基大学研究计算总监

肯塔基大学使用软件定义的网络（SDN）来使科学数据流通过校园网络和云到云。

Bumgardner说：“最初的想法是添加OpenFlow代码以控制现有的校园开关，然后使用高端路由器将它们连接起来。”但是有挫折：所有必要的盒子都不存在OpenFlow代码，由于某些开关如何实现了openflow，因此开放流的不同口味会导致互操作性问题或性能降低。
Then the team tested theAruba 5400R开关系列, an OpenFlow-enabled, high-performance, low-latency, Advanced layer 3 modular switch from Aruba, a Hewlett Packard Enterprise company.

计算科学中心的程序员/系统分析师雅各布·查佩尔（Jacob Chappell）说：“从阿鲁巴拥有SDN的开关使我们能够实现目标。”

智能，可编程网络
"The 5400R switch was one of the few switches that we tested that implemented the OpenFlow NORMAL rule, allowing SDN switches to act as normal switches until an SDN rule was applied," explains Bumgardner. That capability was the key to moving forward."

The 5400R switches work in conjunction with Aruba Virtual Application Networks (VAN) SDN Controller Software, which acts as a unified control point in the OpenFlow-enabled network to simplify management, provisioning and orchestration.

该大学在整个校园内部署了3,000多个支持SDN的港口，以处理科学流，对30,000多名学生，教职员工和教职员工的学术，行政和住宅需求没有任何影响。5400R开关用于分发和访问。

快速，安全的数据流

With SDN, the university can extend its science DMZ all the way to the switch port in a researcher's building or office—and enforce consistent network and security policies. Ordinary traffic moves through the 5400R switches in "normal" mode, while scientific flows from researchers or supercomputer locations are diverted to take a high-bandwidth path.

计算机科学系网络程序员洛厄尔·派克（Lowell Pike）说：“正常规则很重要，因为我们只想修改影响研究人员的流量，能够从敌对来源降低攻击或避免米德箱。”

Right now, the OpenFlow rules are installed manually, but efforts to automate are underway.

粉碎瓶颈
使用SDN为大数据流创建高优先级路径，以减轻传统校园网络中的另一个性能紧缩。电器（或Middlebox）提供流量塑形，负载平衡，防火墙和其他网络功能，可能是一个很大的瓶颈。

派克说：“即使您有100Gbps的网络，Middle箱也可以将北/南速度降至100Mbps。”

但是现在,scientific flows are diverted around these performance-sapping middleboxes, while network policies are enforced via SDN.

对于研究人员而言，数据闸门已经打开。Internet2上校园和研究站点之间的大数据传输速度快88倍。现在可以在不到八个小时内完成以前需要一个月才能完成的转移。

探索一种建立校园网络的新方法

SDN enabled the University of Kentucky to build a smarter, faster, more cost-effective network and support academic collaboration. The ability to accelerate big-data flows using SDN also meant the university needed fewer high-end routers, which delivered savings that could be reinvested into more high-speed switch ports.

Bumgardner说：“使用SDN是部署校园网络的战略方法。”“我们可以将资金推向更高的容量，而不是路由器功能集。”

That strategy is not only critical for big-data flows, but also fits the changing nature of traffic flows as more applications are hosted in the cloud and off-site data centers.

"Even if you're sitting in a classroom, your traffic is going up and out to a data center or the cloud, because that's where the learning management system is," says Bumgardner. "Our research shows that 90 percent of traffic campus is north/south."

With SDN switches and controllers from Aruba, adapting to the changing nature of campus networks has never been easier.