If you have a cable modem, DSL, or office network, you’re one of the lucky ones. You have a high-speed, broadband connection to the Internet that’s always available, always on. You never have to wait to dial, disconnect, or download. You’re connected to the Net via your Mac’s Ethernet jack or AirPort connection, leaving its built-in modem benched.
The real beauty of most broadband connections these days is that they require no setup whatsoever. Take a new Mac out of the box, plug in the Ethernet cable to your cable modem, and you can begin surfing the Web instantly.
That’s because most cable modems and DSL boxes automatically feed all of the necessary configuration settings to the Mac (including techie specs like IP address and DNS Server addresses), courtesy of a glorious feature called DHCP. This acronym means dynamic host configuration protocol, which is tech-ese for “we’ll fill in your Network pane of System Preferences automatically.”
The bad news is that DHCP doesn’t necessarily give you a single, unchanging IP address, which can make it more difficult to use the remote control features of Mac OS X, like dialing in from the road. There is a workaround, however; see Section 21.1.
If, for some reason, you’re not able to surf the Web or check email the first time you try, it’s conceivable that your broadband modem doesn’t offer DHCP. In that case, you may have to fiddle with the Network pane of System Preferences, ...