Duplex settings. My WRT120N access-point has a WAN connection to a Star Band dish. These dishes usually operate at half-duplex, and most ethernet connections, such as the WAN port of a WRT120N, operate at full-duplex. This may be the issue of why I'm having connectivity issues. I need to change the duplex on my WRT120N WAN port. Thanks!

SOURCE: cisco router 1841 connected to serial interface

Hello,
Theres no need to setup for the nat but please check the wan interface and subnet mask ip it has to something else and not 255.255.255.252..Try 255.255.255.240 it must work...

SOURCE: Cicso router 1841 not connecting to the internet

When using Public IP addresses on one interface, usually facing your ISP, and using Private IP addresses (AKA RFC 1918) on another interface, usually facing your LAN, one needs to utilize network address translation (NAT) in order to connect LAN computing resources to the Internet.
Cisco has a fantastic article on how to perform the necessary procedures on their web site.
http://www.cisco.com/en/US/tech/tk648/tk361/technologies_configuration_example09186a0080093f8e.shtml

SOURCE: cisco 857w have had it

connect to the router. in the config there will be a line that reads something like chap username xxxx pass yyyy

Change the user name and pasword to the new ones supplied by BT.

Also change the ip route 0.0.0.0 0.0.0.0 statement to point to the interface for example dialer 0
also change the Ip address of dialer 0 to negotiated

SOURCE: hi everytime i hook up

try to disable your Firewall and tell me the result.

SOURCE: i have a cisco e1000 when i first bought it and

Unplug the modem and router, plug them back in. Wait ten minutes and restart your computer.