About IRDP

ICMP Router Discovery Protocol (IRDP), an extension of the ICMP, is independent of any routing protocol. It allows hosts to discover the IP addresses of neighboring routers that can act as default gateways to reach devices on other IP networks.

IRDP enables hosts to track dynamic changes in router availability. It does not require you to configure the default gateways on hosts or configure hosts to listen to routing protocols to obtain IP addresses of routers.