Changes between Version 5 and Version 6 of ValidationSummary

Timestamp:

Apr 14, 2010, 8:39:45 PM (15 years ago)

Author:

davea

Comment:

--

ValidationSummary

@@ -1 @@
-= Validation, credit, and replication =
+= Validation and replication =
 
-The execution of a job produces:
-
- * The output files;
- * The amount of CPU time used; this may be used to determine how much credit to grant for the result.
-
-In general, neither of these can be trusted, because:
+The results of a job cannot be trusted, because:
 
  * Some hosts have consistent or sporadic hardware problems, typically causing errors in floating-point computation.
  * Some volunteers may maliciously return wrong results; they may even reverse-engineer your application, deciphering and defeating any internal validation mechanism it might contain.
- * Some volunteers may return correct results but falsify the CPU time.
 
-BOINC offers several mechanisms for validating results and credit.
+BOINC offers several mechanisms for validating results.
 However, there is no "one size fits all" solution.
 The choice depends on your requirements, and on the nature of your applications
@@ -34 +28 @@
 of detecting wrong results with high probability.
 
-The credit question remains.
-Some possibilities:
-
- * Grant fixed credit (feasible if your jobs are uniform).
- * Put a cap on granted credit (this allows cheating).
- * If claimed credit exceeds a threshold, replicate the job.
-
 == Replication ==
 
@@ -46 +33 @@
 each job gets done on N different hosts,
 and a result is considered valid if a strict majority of hosts return it.
-
-Replication also provides a good solution to credit cheating, even for non-uniform apps:
-grant the average claimed credit, throwing out the low and high first
-(if N=2, grant the minimum).
 
 One problem with replication is that there are discrepancies