The 'ping' command on most flavors of Unix has a nifty little feature that lets you select which port to ping on. It's handy when troubleshooting network applications. For example, if some wierd app.

This is senior editor Dan Moren. We take networking for granted these days, but it’s still a complicated beast. If you want to go under the hood, Apple includes a suite of tools on your Mac to help ...

From troubleshooting DNS queries and misbehaving network apps to keeping your configurations and passwords organized, these tools have you covered Routing issues, slow network applications, DNS ...