Getting a public ASN is relatively trivial. If you're curious, you can read more about it here: https://www.arin.net/resources/guide/request/ https://www.arin.n

Getting a public ASN is relatively trivial. If you're curious, you can read more about it here: https://www.arin.net/resources/guide/request/ https://www.arin.net/resources/guide/request/ As for whats stopping the announcement of bad routes? Mostly just the ISPs, the big transit providers, and the IX's. The problem isn't the small users. You, as a nefarious individual, are unlikely to be able to cause much real damage. In datacenters where you don't bring your own dedicated transit (expensive), you have to tell them your ASN and IP information so it gets whitelisted. The problem is large players. If China Telecom wants to claim Google's IPs... well the entire world's transit providers may not acknowledge that - but enough will to cause a real problem. More examples: https://en.wikipedia.org/wiki/BGP_hijacking#Public_incidents https://en.wikipedia.org/wiki/BGP_hijacking#Public_incidents