I didn't know either but I found this little snippet: Resource Public Key Infrastructure (RPKI) is a security framework by which network owners can validate an

I didn't know either but I found this little snippet: Resource Public Key Infrastructure (RPKI) is a security framework by which network owners can validate and secure the critical route updates or Border Gateway Protocol (BGP) announcements between public Internet networks. BGP is essentially the central nervous system of the Internet and one of its fundamental building blocks. The main function of BGP is to facilitate efficient routing between Autonomous Systems (AS), by building and maintaining the Internet routing table. The Internet routing table is effectively the navigation system of the Internet and without it, traffic would be unable to flow between its constituent networks. Unfortunately, routing equipment alone cannot distinguish between legitimate and malicious routing announcements, but network operators who implement RPKI validation and filtering can choose to reject announcements from networks not authorized to advertise those resources. In other words, RPKI is essentially a secure identification system for the BGP route information between autonomous systems.