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Forum Replies

  1. First step to protect against DoS and DDoS attacks.

    Further ones may include RTBH, prefix-lists denying the bogon and spoofed prefixes, CoPP on the backplane and rate-limiters.

  2. Hi Harmit,

    It will meet your criteria if you have a default route but yes, you need to add that “allow-default” parameter. Otherwise it will drop the packet even if you have a default route.


  3. Hi Rene,

    I got the uRPF function clearly but want to know how uRPF prevents these spoofing attacks. Actually want want to know “spoofing attacks” Scenario.Sorry for bothering you again n Again .Thanks


  4. Hello Paul

    It really depends on the platform you are using. Higher end platforms (6500/6800 with the appropriate supervisor as well as Nexus platforms for example) will support uRFP occurring in hardware thus providing for fast checking and no taxing of other resources.

    ... Continue reading in our forum

  5. Hello Ajay

    uRPF is a feature that checks the source address on a packet and compares it to the routing table. This means that by definition, uRPF will ONLY function on incoming packets. It can be enabled on any interface, but it will only operate on incoming packets on that interface. Packets that are exiting an interface have already gone through the routing table lookup a

    ... Continue reading in our forum

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