... Hello! I completed a simple userspace tarpit script: http://www.radlinux.org/connexion/browser/branches/0.4.4/lib/cxnet It is not a production solution, but an example of cxnet usage. Whilst not as fast as libnfnetlink and kernel netfilter, cxnet is extremely simple and can be used for rapid net-apps development or in GNU/Linux network studies (e.g., for educational purposes). Cxnet isn''t a complete implementation of netlink and tcp/ip :) Only some features are implemented: full rtnetlink and netfilter support, as well as udp and icmp primitives, are in the todo. -- Peter V. Saveliev