Configure Unicast RPF

For interfaces that carry IPv4 or IPv6 traffic, you can reduce the impact of denial of service (DoS) attacks by configuring unicast reverse path forwarding (RPF). Unicast RPF helps determine the source of attacks and rejects packets from unexpected source addresses on interfaces where unicast RPF is enabled.

If you want to configure unicast RPF, your router must be equipped with the Internet Processor II ASIC. If you enable unicast RPF on live traffic, some packets are dropped while the Packet Forwarding Engine is updating.

The following sections describe unicast RPF in detail:

• Configure Unicast RPF Strict Mode
• Configure Unicast RPF Loose Mode
• Unicast RPF and Default Routes
• Unicast RPF with Routing Asymmetry
• Example: Configure Unicast RPF