An interesting, non-obvious look at how social networking sites, and to a lesser extent web 2.0 websites are affecting Internet performance.

CircleID: A typical MySpace profile page is a rich assortment of images and blogs posted from friends. Users can post videos and flash-based content, as well as links to favorite songs in MP3 files. In most cases, each of these content pieces is stored in a separate DNS domain. For example, each image belonging to a friend is retrieved from a distinct URI. This means that retrieving and displaying a profile page may require hundreds of DNS lookups in the background—compared to ten or so lookups for a ‘standard’ B-to-C web page.

MySpace is one of the most visited sites on the Internet. Each of those page downloads may account for ten times or more the amount of DNS traffic of a typical web page visit. Here is an important clue to the recent, unusually high increase in DNS traffic. And, alas, there is more to the story than meets the eye.

Because DNS queries are very small and generally very efficient, I don’t think this is a major problem, but it should lead to innovation in the space.