If you experience poor network performance, it can sometimes be difficult to tell whether that's the result of a conscious distributed denial-of-service (DDOS) attack or just poor software design somewhere in the stack. A recent incident at YouTube highlights how the latter can cause major problems, even when the software involved isn't under your direct control.
Google Operating System highlights part of a presentation made at the Google I/O conference which showed how unexpected phone behaviour was identified while developing YouTube's adaptive streaming feature, which tries to intelligently download video data to avoid buffering:
If a popular mobile handset manufacturer releases a software update that opens TCP connections and doesn't close them, you get something that looks like [the graph above]. A globally distributed denial of service attack on your servers that lasts for months. And there's basically nothing you can do to avoid this situation except sit and wait and hope they release an update.
The presenter didn't say which handset manufacturer was involved, but Google Operating System speculates that iOS is the most likely candidate, in large part because iOS users are much more likely to update than users of other platforms. The lesson? Problems with dealing with different mobile platforms aren't limited just to screen size.
YouTube And a Distributed Denial-of-Service Attack [Google Operating System]