The answer was blockname, a proposal that uses
the existing domain name system, but falls back to the decentralized system when it fails to find the device it's looking for on the public DNS.
Jake Feinler's work in developing the ARPANET Directory that «prefigured by decades our age of searchable, reachable online social connections» as well as the WHOIS database that still
exists today, and her contribution to the organization of the
domain name system with the creation of the first top level
domains -LRB-.