Cisco - Windows Firewall & Router
You able to generate packet/ping from your PC to but you can't receive.
It is like a hole in a firewall.
Facts that we can acquired:
1. Windows PC firewall do not block L2 packet for i.e. ARP packet, hence Router able to resolve your windows PC mac address a.k.a your window PC physical address. You can view/examine your physical address with ipconfig /all command.
2.