This little gem is probably one of those diagnostic tools that — like BackOrifice and Metasploit Framework — in the right hands is a good diagnostic tool and in the wrong hands is a bad diagnostic tool: http://www.serversniff.net/index.php “ServerSniff.net – Your free “Swiss Army Knife” for networking, serverchecks and routing with many many little toys and tools for administrators, webmasters, developers, powerusers und security-aware users. “Tools for webmasters and developers: “Benchmarks and informations about servers, routing, IP-Stacks, encryption, security, nameservers and domains

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New sniffer soon coming to a server near you