Dave Stephenson位于移动网络中最重要的努力之一，安全地自动移动到Wi-Fi热点之间的牧羊犬和其他设备。
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Stephenson has been a key player in the development of Hotspot 2.0, a set of specifications for how users can move among Wi-Fi networks operated by different service providers without having to look up network names and enter passwords. He remains chairman of the Wi-Fi Alliance Hotspot 2.0 Technical Task Group even though he just changed day jobs: After almost 14 years at Cisco Systems, Stephenson has joined Ruckus Wireless as a senior principal engineer.
Ruckus is something of a Wi-Fi upstart, a fraction of the size of Cisco, the dominant player. Stephenson heard the company's name come up frequently with carriers, talked to its top executives and was impressed with the leadership team, he said. He'll help Ruckus form a system architecture group to make sure all of the company's products work together as an overall architecture. But with its focus on wireless LANs for service providers, Stephenson said, Ruckus was also a good place to keep up his work on Hotspot 2.0.
“我喜欢完成我的开始，所以这对我来说是一个非常好的机会，”斯蒂芬森说。
What the Hotspot 2.0 group started working on in mid-2010 was nothing less than a way for users to roam from one Wi-Fi hotspot to the next just as easily as they can from one carrier's mobile network to another's. "We wanted it to be as automatic and secure as cellular," Stephenson said.
Mobile users can already move automatically onto Wi-Fi networks operated by their own carriers, but getting onto the many hotspots run by other service providers is usually harder. Beyond just the technical issues, carriers want Wi-Fi roaming agreements to work like cellular roaming deals, meaning that they get paid when another service provider's customers use their networks. Hotspot 2.0 is one of several initiatives aimed at making practical Wi-Fi roaming work.
今天，Hotspot 2.0在实验室和运营商网络中进行了试验，斯蒂芬森预计将在今年下半年看到商业部署。一个名为无线宽带联盟（WBA）和GSM协会的服务提供商组也正致力于使服务提供商更容易设置商业Wi-Fi漫游协议。
Stephenson is optimistic about the future of Wi-Fi roaming, which should help carriers offload the growing volumes of data from their cellular networks and keep offering the roaming capability that subscribers are used to. He knows how much work has been required to make that possible, having been involved in several parts of the effort.
在IEEE 802.11U上建立的热点2.0组，在2005年开始开发的802.11 Wi-Fi标准下的自动切换机制。802.11U规范为Wi-Fi网络运营商提供了一种标准的方式Stephenson说，自动告诉移动设备关于他们的漫游关系。利用该信息，设备可以使用可能为这些网络中的一个提供的任何凭证加入网络。
HotSpot 2.0将具有包括安全性的其他组件的功能组合，定义使用标准Wi-Fi加密保护热点上的所有会话的方法。去年6月，Wi-Fi联盟使用完整的Hotspot 2.0标准来设置其Passpoint认证程序，其中它测试和证明Wi-Fi设备在标准下进行互操作性。
Meanwhile, the WBA has been working on the back end to help make Wi-Fi networks capable of offering roaming. Under a program called Next-Generation Hotspot (NGH), the WBA has been overseeing trials for about 18 months in which devices roam among networks, said Shrikant Shenwai, CEO of the WBA.
In December, the WBA announced its Interoperability Compliancy Program, which set out a common set of requirements and procedures for Wi-Fi roaming. It includes guidelines for security, device authentication, network selection, and charging and billing. There is also a program for carriers to assess their compliance with the guidelines. If would-be roaming partners both comply, it should be easier for them to set up a roaming relationship, Shenwai said.
WBA还与GSMA合作，分别协调Wi-Fi和细胞的漫游系统。持续努力应该帮助运营商将Wi-Fi纳入其定期会计和计费系统，使得与许多服务提供商建立漫游关系。
作为一名工程师，Stephenson表示，Hotspot 2.0只面临着“常规”技术挑战，具有来自蜂窝和Wi-Fi世界之间的差异的更大问题。他说，教育都需要两种方式。
In the deployment phase of Wi-Fi roaming, the carriers themselves face the biggest challenges, Stephenson said. "They are big, have a lot of momentum to overcome, have to make sure via testing and trials that the Hotspot 2.0 technology is ready and that their networks are ready."
Stephen Lawson covers mobile, storage and networking technologies forIDG新闻服务。Follow Stephen on Twitter at@sdlawsonmedia。斯蒂芬的电子邮件地址是stephen_lawson@idg.com