In this Hut 8 Techtorial ‘Deep Dive’ we take a very detailed look at the BGP OSPF Extended Community Attributes and specifically, the Route Type. We examine RFC 4577, where the Route Type is defined and described, and then walk through each of the different scenarios to see how and why you will see the OSPF Route Type values you do when using OSPF as the PE-CE routing protocol in an MPLS L3 VPN environment. Enjoy!