Quorum replication

WCG is already using "single replication" for some of their applications (sub-projects so to speak). They keep a "reliability score" of each host, which basically determines the ratio in which these hosts get sent tasks for "single" or "validated" workunits (both are available). Even a highly "reliable" host gets sent a task that's compared to another task of the same workunit from time to time, so they occasionally verify their reliability records.

Yes, there still is a chance that if two people use the same "broken" application on Einstein@home the results of these two are compared, and so wrong results might end up as canonical. However with the increased number of compute cluster machines that only run "official" apps this case has become rather unlikely.

The techs (like me) discussed "single replication" with the scientists behind Einstein@home when we switched to "server assigned credit", which allowed us to reduce the initial replication from 3 to 2 (I think S4 was the first run to feature this). The scientists insisted on at least a quorum of 2 for verification. I don't think they feel differently about that nowadays.

BM