The video demonstrates configuration of OSPF as PE-CE routing protocol in Cisco MPLS VPN. In addition to basic OSPF configuration, we will go through more advance scenarios of dualed-home site and sites with a backdoor link, and try to understand how a use of Sham Link can prevent a backdoor link from being preferred over MPLS, and how Down-Bit and how Domain Tag can prevent learnt routes from being re-advertised out of the site. We will also look at the Domain ID and the affect that it has on OSPF LSA type.