It may even been simpler than that and they might not even need 'upstream' any more. They may not even have upstream for many things, given their scale now, the

It may even been simpler than that and they might not even need 'upstream' any more. They may not even have upstream for many things, given their scale now, they probably just peer to Tier 1, if they even need that any more! (they were actually just as big as Tier 1 folks back in 2010![0]. Google has been buying up 'dark fiber' for years and has thousands of miles of cable connecting their data centers. They can certainly handle petabit/s levels of traffic inside the datacenter[1], it's not that much of a stretch to think that they can handle double digit terabit/s through their collective external fiber links. Also, just think about their normal level of operation. Even just all the Android devices feeding data back and forth, let alone analytics, maps, gmail, search etc etc. They've got 36 data centers and co-locate in more than 60 public exchanges (and that was in 2010!), not to mention the Google Global Cache (GGC) servers inside consumer networks across the globe. Their scale is ridiculously large. I suspect that they actually can't be DDoS'd in the normal 'chuck traffic at them' sense. [0] http://www.theregister.co.uk/2010/03/17/the_size_of_the_googlenet/ http://www.theregister.co.uk/2010/03/17/the_size_of_the_goog... [1] http://googlecloudplatform.blogspot.co.uk/2015/06/A-Look-Inside-Googles-Data-Center-Networks.html http://googlecloudplatform.blogspot.co.uk/2015/06/A-Look-Ins...