If you are a small project collaborating with the X-Bone group, we invite you to request a key from us directly. We manage our own key signing certificate authority, and can sign keys on request. However, because there are two alternatives available, this option is limited to groups working directly with us. You can purchase a key from a commercial certificate authority, such as Verisign . You can configure your own certificate authority, as we have done, and sign your own keys.
More information is available in the installation instructions.
The X-Bone uses multicast for resource discovery, to reduce configuration. IP was chosen precisely because it is a unifying layer. IP runs over anything. By focusing the X-Bone on IP, we can run over anything IP runs over, which is, in short, anything. Customizing the X-Bone to other protocols would defeat its goals of ubiquitous deployment and recursion.