A blogging network is not the same as a blog directory. It is a collection of interconnected blogs organized around a central unifying theme. One example of a blogging network is the Educational Bloggers' Network. The network, known as EBN for short, is a community of teachers and other education professionals who use blogs for teaching and learning. Networks generally require that users register, but as in the case of EBN, registration is often free. You can find blogging networks on your topic of interest by doing a Google search or searching a blog directory.