&gt; Probing just 30% of the top prefixes is likely not enough for their use case. Probing is also an after the fact approach. Fastly needs a solution which will give best possible path from first packet. &lt;<p>Considering that Fastly deploys PoPs and not colos or datacenters, I think that the top 30% of their transit routes would be the lionshare of non-peer activity. Fastly&#x27;s PoPs are generally at (or have reach to) the largest Internet exchanges for peering purposes. Peering routes are generally the best, cheapest, most concise routes you can get. You don&#x27;t need a big, expensive router when you&#x27;re in an exchange&#x27;s peering mesh. Considering that you&#x27;re only handling local traffic (by design of having multiple PoPs), peering plus two default transits will probably optimize for the traffic that matters most.<p>Also as mentioned, you can&#x27;t really determine &quot;best possible path&quot; without probing. You can see what BGP tells you, but that&#x27;s not always the best possible path. People that run networks know this. That&#x27;s why things like FCP&#x2F;IRP&#x2F;RouteScience exist (for better or worse).<p>&gt; Different game indeed. Netflix just cares about throughput, Fastly also needs low latency, hence the need for more optimizing. &lt;<p>Sure, but you won&#x27;t get that optimization from BGP. In a Fastly PoP, you&#x27;re mainly dealing with in-country or in-region eyeball networks. If you buy transit from 2-3 major networks, BGP probably won&#x27;t help you with those eyeballs. The path length will probably be the same (the eyeballs either peer or buy transit from large tier 1s). You generally can&#x27;t trust MED to do anything useful with it, so that&#x27;s out. Those are the only 2 things BGP can use to impact route selection. If path length and MED are the same, it&#x27;s a coin flip as to which path to take (not really as the first installed route is the winner).<p>If you just took default routes and peered locally, you&#x27;d be much better off in a PoP scenario than trying to re-invent route reflectors and taking full BGP feeds.