nanog mailing list archives
Re: Interesting BFD discussion on reddit
From: Hugo Slabbert <hugo () slabnet com>
Date: Tue, 17 Feb 2015 08:37:34 -0800
Because BFD packets can get routed across multiple hops. Unlike EBGP where you connect to a peer in a different AS and you have a direct connection, BFD packets can traverse multiple hops to reach the endpoint.
Then what's this "multihop" knob I have available in my BGP config? Again, as Rob pointed out, "can" vs. "should" is a good consideration here, but unless I'm missing something both EBGP and BFD "can" do multihop...so...?
-- Hugo On Tue 2015-Feb-17 07:42:20 +0530, Dave Waters <davewaters1970 () gmail com> wrote:
Because BFD packets can get routed across multiple hops. Unlike EBGP where you connect to a peer in a different AS and you have a direct connection, BFD packets can traverse multiple hops to reach the endpoint. In case of multihop BFD the BFD packets also get re-routed when the topology changes so you can almost never bet on the TTL value to secure the protocol. Dave On Tue, Feb 17, 2015 at 7:03 AM, Rob Seastrom <rs () seastrom com> wrote:Dave Waters <davewaters1970 () gmail com> writes: > http://www.reddit.com/r/networking/comments/2vxj9u/very_elegant_and_a_simple_way_to_secure_bfd/ > > Authentication mechanisms defined for IGPs cannot be used to protect BFD > since the rate at which packets are processed in BFD is very high. > > Dave One might profitably ask why BFD wasn't designed to take advantage of high-TTL-shadowing, a la draft-gill-btsh. -r
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Current thread:
- Re: Interesting BFD discussion on reddit, (continued)
- Re: Interesting BFD discussion on reddit Glen Kent (Feb 15)
- Re: Interesting BFD discussion on reddit Saku Ytti (Feb 16)
- Re: Interesting BFD discussion on reddit Eygene Ryabinkin (Feb 16)
- Re: Interesting BFD discussion on reddit Glen Kent (Feb 16)
- Re: Interesting BFD discussion on reddit Saku Ytti (Feb 16)
- Re: Interesting BFD discussion on reddit Sudeep Khuraijam (Feb 20)
- Re: Interesting BFD discussion on reddit Glen Kent (Feb 15)
- Re: Interesting BFD discussion on reddit Saku Ytti (Feb 16)
- Re: Interesting BFD discussion on reddit Dave Waters (Feb 17)
- Re: Interesting BFD discussion on reddit Rob Seastrom (Feb 16)
- Re: Interesting BFD discussion on reddit Hugo Slabbert (Feb 17)