You can do some pretty simple testing of ports and network communications using strategies I’ve outlined in the past with tcpdump, trace route, telnet, curl, stroke and of course ping. However, netcat has a few interesting things you can do with it; namely actually run a port super-quickly to test traffic between subnets, forcing scans of ipv6 traffic, debugging sockets, keeping connections alive, parodying through SOCKS 4 and 5 and just checking for daemons that are listening rather than actually sending data to them. In this first example, we’re going to just check that Apple’s web server is accessible (adding -v for verbose output): /usr/bin/nc -v www.apple.com 80 The result would be pretty verbose…