There is a system for entering the number of the ball that falls out in a lottery game. It consists of two computers operated by two different people. They each have to enter the ball number they see so it is double-checked. What would you call such thing in English? Double-entry? Double-check?
I think "double-checked" or "cross-checked" would be more accurate than "redundant" here. If the intention was that the system was still usable even if one of the computers fails altogether, that would be a redundant system, but (I assume) it isn't; the cross-checking that both operators agree on the numbers is a necessary part of the system if we want to detect errors.
"cross-checked" is perhaps more precise; the point is to have two independent sources to check against each other, whereas "double-checked" could be a single source being looked at twice. (Though ultimately there's one source, the actual ball with the number.)
(The next stage would be to have three operators, and to accept results if two out of three agree. Then the third computer is redundant for error detection, but not for error correction.)
In engineering, we would call it a redundant system.
redundancy: (1b) (engineering) The inclusion of extra components that are not strictly necessary to functioning, in case of failure in other components
This kind of entry is called Two Pass Verification or Double Data Entry.
Two people key data into a system, and then the differences are displayed at the end for verification.
Two-pass verification, also called double data entry, is a data entry quality control method that was originally employed when data records were entered onto sequential 80-column Hollerith cards with a keypunch. In the first pass through a set of records, the data keystrokes were entered onto each card as the data entry operator typed them. On the second pass through the batch, an operator at a separate machine, called a verifier, entered the same data. The verifier compared the second operator's keystrokes with the contents of the original card. If there were no differences, a verification notch was punched on the right edge of the card.
You can read more about it here: https://en.wikipedia.org/wiki/Two_pass_verification.
Although it doesn't describe the situation precisely in and of itself, the word independent (meaning 3) is very important here - the number is entered twice, each entry being independent of the other.
Hence a full description of the system (in as few words as I can make it and still fully describe the system) is:
The number is independently entered twice, with the two entries cross-checked for consistency
I don't think that independent cross-check in and of itself is a clear definition.
- Definition for independent provided by dictionary.reference.com
- Credit to armb for cross-check
This kind of procedure is based on what is sometimes called the four-eyes principle.
The four eyes principle is a requirement that two individuals approve some action before it can be taken. The four eyes principle is sometimes called the two-man rule or the two-person rule.