How to configure a PPPOE server in 2008 R2 so that My test mobile can do a ppoe session via router. trough Wan Mini Port PPPOE

Hi All, 

I have a typical issue, I have to configure a PPPOE server in 2008 R2 so that My test mobile can do a ppoe session via router.

I have configured AD, DNS, DHCP and RAS on same machine, when I open Ports properties the In bound rules of Wan Mini Port PPPOE is faded out.

I am able to do successful pppoe connection from another machine  via connecting  Null modem cable, however I need to make it work on WAN Mini PPPOE  port. 

Do I need to configure any modem to my server to enable  Wan Mini Port? if so which one to purchase?