An "Add" PDU is being sent to a client, which causes a route to be added to its IP route tables.

address1 is the destination IP address of the route.

The interface is the name given to the interface during NCP generation.

address2 is the IP address of an intermediate router or zero if the destination is directly connected.

The metric is the relative cost of using this route as opposed to another route.

The type is either Host, Subnet, or Network and indicates the route type being added.