In an approach to an overlay network capabilities exchange for reserving high priority handling of packets, a computing device creates a transport protocol port map that correlates one or more inner protocols with one or more outer transport protocol port numbers. The computing device creates a priority bit re-map table that correlates one or more outer transport protocol port numbers with one or more levels of priority. The computing device then receives a packet having an associated protocol and an associated port number, and determines, based on the associated protocol and the associated port number, that the packet requires a level of priority of the one or more levels of priority that guarantees loss-less delivery of the packet.