BGP lockdown hints

As I am preparing talks for the upcoming WISPAPALOOZA 2014 in Las Vegas I am making some notes on advanced BGP.  If you are running BGP, and want to lock it down a little here are some general hints.  If you want more attend my session in Vegas or look here afterwords for the full rundown.

General Hints for BGP filter.

1.Filter all all the bogon addresses unless you have a specific need. If you have to ask you probably don’t have a need so filter it. Bogons are:,

2.Don’t accept your own IP space from upstreams.  There should be no reason someone is advertising your own IP space back to you that is not a downstream customer.  I mean dowstream as to someone you have assigned your own IP space to.

3.Limit the maximum number of prefixes your router will accept.

4.Most ISPs don’t announce anything less than a /24.  Configure your filters to not accept anything smaller than a /24 unless you have a specific need to do so.

5. Separate iBGP from eBGP.

6.Understand the defaults for the platform you are using.