Case.1 We know that when router connected via point to point(PPP) protocol then ARP isn't used to know the destination Mac address.
Case.2 When two router connected via PPP as well as Ethernet which is PPPoE, then also ARP isn't used to know destination Mac address.
My question is for case2 PPPoE request frame is used to know the destination Mac address?
And in PPPoE request frame PPP is also used as well as in Ethernet frame PPPoE frame(which contained PPP frame) also used to know the destination Mac address?
And in Ethernet frame destination address should be ff:ff:ff:ff?
Like the below image: