This is a followup on yesterday's post about how little Google/YouTube pays for bandwidth. Google wants to promote peering with ISPs, so they give presentations at ISP meetings. After reading yesterday's post, Alex Benik of Battery Ventures sent me a link to this presentation given by Google at a 2008 meeting of the Latin America and Carribean Internet Addresses Registry (LACNIC).
As expected, Google peers with as many relevant ISPs as possible. For the ISP, peering with Google eliminates their upstream costs for traffic to Google. Since Google represents a substantial volume of traffic for most ISPs, this is a big saving. As of May 2008, Google was present in 33 public Internet exchanges around the globe, so major ISPs already have connections in places where they can peer with Google. The minimum qualifications are 5 Mbps of Google traffic and the ability to interconnect using Gigabit Ethernet at one of these 33 major Internet exchange points.
Google Global Cache
What's interesting is Google's caching strategy. Just as Akamai puts servers in ISP's local facilities, Google is providing a distributed cache for their content. This available to larger ISPs and allows them to serve Google content directly at the edge of their networks, thus reducing traffic on the ISP's backbone network. Here's a representative rack that Google provides to the ISP.