For the Internet, New Connections With Peering - NYTimes.com

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What is clear is that today a significant portion of Internet traffic does not flow through the backbone networks of giant Internet companies like AT&T and Level 3. Instead, it has begun to cascade in torrents of data on the edges of the network, as if a river in flood were carving new channels.

Some of this traffic coursing through new channels passes through public peering points like Mr. Pozar’s. And some flows through so-called dark networks, private channels created to move information more cheaply and efficiently within a business or any kind of organization. For instance, Google has privately built such a network so that video and search data need not pass through so many points to get to customers.

For the Internet, New Connections With Peering - NYTimes.com