TraceRoute,DNS lookup, ping http://hyperarchive.lcs.mit.edu/cgi-bin/NewSearch?key=whatroute Monitor TCP Activity http://hyperarchive.lcs.mit.edu/cgi-bin/NewSearch?key=mac+tcp+watcher DNS Server for the Mac http://horton.austin.apple.com/Apple.Support.Area/Apple.Software.Updates/US/Macintosh/Networking-Communications/Other_N-C/MacDNS_1.0.3.sea.hqx