One of the three pillars of mission-critical systems is data reliability – a significant concern in data centers worldwide. Data reliability can be ensured via a special configuration that compares the operation of one sub-system to another sub-system running the same applications. Verification may be accomplished by comparing results generated by the two sub-systems at specific synchronization points. If the results agree, the sub-systems are operating properly, if not, corrective action can be taken. This article suggests that the comparison of transaction-processing output via a Transaction Indicia Matching (TIM) module is a significant improvement over the use of a Logical Synchronization Unit (LSU), which represent a single point of failure in a system. A version of a TIM can be implemented with HPE Shadowbase synchronous data replication.