This config is for the Cisco 1800 series router running IOS 12.4. IOS 12.4 has some command and syntax changes in reguards to interfaces and configuration commands for PPPOE. This config was submitted by my good friend Pedro Rivera.
Configuring a Cisco router to use the WIC-1ADSL card is one of the most commonly asked question by people in the Cisco forums. There are some interesting and compelling reasons to use a WIC card instead of connecting PPPOE through the ADSL modem in bridged mode. One of the most compelling reasons is the ability to use advanced QOS features such as interleaving and fragmentation. Because the DSL WIC card shows up as an ATM WAN interface, the router is able to perform those advanced Quality of Service features. The overhead of encapsulating a packet in PPPOE and sending it to the modem over some length of cable is also a reason to use a WIC card instead of the modem.
It is important to realize that with most ISP’s you can configure the connection to use either PPPOA or PPPOE, the difference in configuration is very subtle however it can save you a couple of bits of overhead as PPPOE is encapsulated more time Than PPPOA. So without further a due: (more…)