In the past couple of weeks I had a a few posts on what peering is and who pays whom for what. Here's my book review that describes the topic in detail and here's a link to my post on the difference between network neutrality and Internet Service providers (especially in the US) trying to charge the content providers for traffic. Today I came across two posts on Level-3's blog (see here and here) that gives their perspective on the matter. An interesting read and a practical example of the theory I discussed in my previous blogs. Well worth the read!