The value of vRtrIfuRPFCheckMode specifies the mode of unicast RPF
check.
In 'strict' mode, uRPF checks whether incoming packet has a source
address that matches a prefix in the routing table, and whether the
interface expects to receive a packet with this source address prefix.
In 'loose' mode, uRPF checks whether incoming packet has source
address with a corresponding prefix in the routing table, however
'loose' mode does not check whether the interface expects to receive a
packet with a specific source address prefix.
This object is valid only when value of vRtrIfuRPFCheckState is set to
'enabled'.