I have CenturyLink (CL) DSL, have had this in some form since 2003. Have gone through many modems, see links at bottom of page for old config pages. We had a powerfail last week, and when it came back, my old C3000Z was having problems with thousands of FEC errors per hour, though it did still basically function, albeit jerky. I called Centurylink, they sent a tech out a few days later, and as I lease the modem, they just provided me a new one. This is a C4000BZ, not sure who makes it.

My setup is to have DHCP turned on for the inside LAN; any computer plugged into it, or any computer using wireless would simply be allocated a safe internal IP address.

However there are two servers that need to be available to the outside world. These each have a static route for access.

I have a block of static IP addresses from CenturyLink. When you get this, you are actually allocated a block of 8 (hence the .248 subnet mask), however only 5 are available to you for use.

Here are my settings to implement this:

• Browser into modem http://192.168.0.1/ (Note that FireFox does not work well, use Chrome)
• Advanced Setup->Security->Administrative Password
• Wan Settings
• ISP Protocol: "auto" (selected is PPPoE)
• PPP username, pswds filled in, "Auto Connect" is checked, "No credentials" is NOT checked
• IP addressing type: "Block of Static"
• Your gateway address is provided by the phone co, it's 1 higher than the last usable IP address in your block
• subnet mask: 255.255.255.248
• Here's the important one -- select "Public Static Subnet". This makes every internal address available externally - see below!
• Dynamic DNS; this indicates to fill in automatically (this is not the same as "dyndns").

• On each server you must hardcode the IP address you'll be calling it up with.
• Other internal devices just leave t DHCP - the modem will provide this for those devices that ask.