Fundamental problem: either the distributed thing will be an extremely easy target for DoS attacks -- just because the service is distributed doesn't mean the a

Fundamental problem: either the distributed thing will be an extremely easy target for DoS attacks -- just because the service is distributed doesn't mean the attacker need be; the attacker can be as monolithic as he wants to be -- or, it will be only superficially distributed, and actually hosted on some honking big central infrastructure. Things that are smaller than Google, Amazon, or Facebook can be DoSed into total oblivion. Abuse is the greatest unsolved problem of distributed systems.