Randy Bush wrote:
It has been routinely observed in nanog presentations that settlement free providers by their nature miss a few prefixes that well connected transit purchasing ISPs carry.
just trying to understand what you mean,
o no transit-free provider actually has all (covering) prefixes needed to cover the active space, but
o one or more reasonably small subsets of the set of transit-free providers do cover the whole active space.
If your goal is near-complete coverage, under normal circumstances you need more than one (your subset). Settlement-free provider peering spats are a degenerate condition of the normal state of affairs. The non-settlement-free provider has some subset already. Pointing default into a settlement-free provider, that is deliberately not speaking to another is obviously a recipe to lose data, which speaks to the question of whether one should as for a full table from settlement free upstreams. My somewhat obtuse point was that this isn't some wild west frontier justice sort of affair, but rather, the normal state of affairs.
randy