关于为何《优酷视频使用http协议，而不是使用Rtmp协议呢》的回答

在水木社区看到这样一篇帖子：

http://www.newsmth.net/nForum/#!article/VideoCoding/26094

回答如下：

【 在 ohcabinet 的大作中提到: 】 

Flash Video content delivered using HTTP lacks intellectual property (IP) protection. There is no way to limit offline access to Flash Video content served over HTTP: The Web browser caches Flash Video files
in its temporary storage, which can be accessed by the user after browsing the site. As such, content producers and licensees don't distribute Flash Video content over HTTP; RTMP is the preferred protocol. 
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