[Don Joe]

CRC? TOD?

Cyclic Redundancy Check, Time of Day.

The first is a method of detecting if the contents of a piece of data have been tampered with, sort of like a checksum, but more robust. The second is self-explanatory.

[expatpat]

Thanks. CRC seemed familiar, but I couldn't place it. I hadn't run across the TOD acronym, but you're right: that would be very useful check.