True or false: The Tier-1 and Tier-2 Historians do not have to be on the same network.

The statement is true because Tier-1 and Tier-2 Historians can operate independently on different networks. This flexibility allows for various configurations depending on the architecture of the system and specific requirements regarding data flow and security. For instance, in a distributed environment, it might be beneficial to separate networks for regulatory compliance or performance optimization.

In many cases, Tier-1 Historians are designed for high availability and real-time data processing, while Tier-2 Historians may focus more on historical data storage and less frequent access. These differences in purpose and functionality mean that they can be positioned on separate networks without impacting their core functions, as long as the necessary communication protocols and data transfer mechanisms are established between them when needed.

Other options imply certain conditions or limitations that aren't universally applicable to the real-world deployment of these systems. Thus, the true nature of their operational requirements is accurately reflected in the statement that they do not have to reside on the same network at all times.