Urpf Operation - HPE FlexNetwork 10500 Series Security Configuration Manual

uRPF operation

Figure 146 shows how uRPF works.
Figure 146 uRPF work flow
Checks the received
packet
Multicast destination
address?
No
All-zero source
address?
No
Uses source address to
look up the FIB table
Matching FIB entry
found?
Yes
InLoop interface
found?
No
Default route found?
No
Do interfaces match?
Yes
Discards the packet
End
1. uRPF checks address validity:
uRPF permits a packet with a multicast destination address.

For a packet with an all-zero source address, uRPF permits the packet if it has a broadcast

destination address. (A packet with source address 0.0.0.0 and destination address
Yes
Yes
No
Yes
InLoop receiving
Yes
Default route
allowed?
Yes
No
Loose check?
Yes
Broadcast
destination
address?
No
Yes
interface?
No
No
No
541
Yes