I work for a small ISP that is about to enter into the world of public peering for the first time. We are currently looking for best practices on bgp ingress filtering when connecting to a public peer at an IX.
Are there any recommendations on bgp ingress filtering that should be done which you may not do in other circumstances? The usual filtering will be in place (bogons, sua, our own prefixes etc.). We were also considering filtering on as path length of <= 3 (AS peer at IX, plus their customers and potentially one level deeper) and of course setting a maximum-prefix size so that we don't get overwhelmed if someone accidentally decides to advertise the complete bgp table.
Based on your experience, are there any other considerations which should be taken into account?