After you've removed the 851W or 871W from the box and plugged in the power adapter, plug the supplied console cable to a valid serial port on your computer. If you have a laptop that doesn't have a serial port, you will need to get a USB-to-serial adapter. For ideal testing purposes, you'll need a wireless LAN-capable laptop and a desktop computer. Plug the desktop computer in to F1 or FastEthernet port 1 (this is the second port from left in figure above, since F0 is the first). Most desktop computers have at least a COM1 port, so you can use that as the console configuration computer. You plug the RJ45 end of the console port in to the right-most RJ45 port labeled "console." If all you have is the laptop, you can use that to test the wired and wireless functionality.
For more details on the hardware setup procedure, see the quick start guide from Cisco on the 850 and 870 series routers. (This is actually a fairly decent hardware guide from Cisco.)
Wiping the default configuration
The first thing I do with all the newer Cisco routers is wipe the default configuration on them. Old school routers didn't have any username or passwords assigned to them, but these new devices are different. You have to first log in with username "cisco" and password "cisco". The "c" in "cisco" may need to be capitalized on certain access points and routers, but most of the newer Cisco devices are like this. Once you've logged in, you'll need to type the following commands:
- enable
- write erase
- reload (confirm reboot)
Once the router is rebooted, you'll see a "router>" prompt and no passwords will be required. Now, you're starting with a clean slate. Unlike last time, when we had to create some VLANs, the standard "advanced security" IOS feature set on the 871W will not support this and the 851W won't do it at all regardless of the IOS installed. You now need to enter global configuration mode by typing the old "config t" command.
CLI configuration template for Cisco 851W or 871W
I've always thought that the Cisco configuration guides were too difficult to use, with their inline comments and hints, so I've created my own configuration template system in Microsoft Excel. Thanks to our development blogger Justin James, who wrote a quick replacement button that automatically generates a ready-to-use configuration output, we have a truly useful new tool for documenting and creating new CLI configuration files.
For this particular tutorial, I've created three templates for the Cisco 851W or 871W standard "advanced IP" IOS, embedded with Justin's new rapid replace functionality. The first template is for DSL PPPoE implementations. The second template is for DHCP or cable modem Internet connections. (Note that for cable modem implementations, you should reboot the cable modem. It tends to lock itself down to a certain MAC address, which will cause problems for your router unless you reboot.) The third template is for static IP WAN implementations.
