I've trying to gain certain real world knowledge through this case study. I use ADSL from ATT. I configure the modem as bridged mode. Then I connect my own wireless router to this modem using ethernet cable.
Actually this ADSL modem (TP-link) has its own router integrated. So, I guess
#1 between my own router and the TP-Link's router, it's just two networks connected with an ethernet cable. No WAN.
#2 internal to the model, a certain WAN protocol is used between the internal router and the modem component. Am I right? If so, what is it? I thought it would be PPoE. But then what is the bridged mode?