transit across the ixs

[Randy Bush]

you might be amused to write a bit of code to see if your ix peers are
giving you next-hops of other provider(s).  it is clear that a number of
providers are selling transit across the ixs.  not at all cool.

we can't decide whether to force next hop on their routes, or keep watching
and de-peer them if they do not cease and desist.  what do others do in this
circumstance?

randy