Amazon Web Services (AWS) not only designs its own switches, but it also runs its own fiber network to connect its cloud regions. And as James Hamilton, Amazon distinguished engineer, explained in his Amazon re:Invent talk Tuesday night, Amazon is expanding that network with a new trans-Pacific cable that broke ground in New Zealand last week.

AWS CEO Andy Jassy will give Wednesday morning's keynote, and CTO Werner Vogels will talk on Thursday. But Hamilton's talk was a particular treat for cloud and networking geeks, because he has the OK to divulge what's inside AWS' networks and data centers.

One purpose of his talk was to convey the physical vastness of AWS. Amazon operates 14 AWS regions right now, with four more to be added during the next year.

And a "region" is more than just a location, he explained. Regions host the AWS data centers, but there's some multiplication involved. Each region comprises two to five availability zones, which themselves encompass one to eight data centers apiece. Several of the availability zones house more than 300,000 servers apiece, he said.

To connect the regions, Amazon chose to run its own global fiber network. The company is its own service provider, because that was the best way to ensure reliability.

"My rule is: If you've got a packet, the more people that touch it, the less chance it has of being delivered," Hamilton said.

The new trans-Pacific cable is the latest leg of that network. Hamilton referred to it as the Hawaii cable, but it wasn't clear if that's just an informal moniker.

It will stretch across 14,000 kilometers of total distance, running fibers that deliver 100 wavelengths running 100 Gb/s of bandwidth each. At its deepest point, the cable will be 6,000 meters beneath the surface.

As Amazon knows, subsea cabling is an expensive job, and not just because of the obvious difficulty of installing something on the ocean floor. There are extra pieces that a terrestrial network doesn't require. For example, the optical signals need to be regenerated in order to survive the distances involved, which means installing repeaters every 60 to 80 km, Hamilton said.

And those repeaters need electrical power. "Those really, really long extension cords you see on some lawns? Doesn't feel like the right thing," he said.