What do checksums help to detect during data transmission?

Checksums are a crucial mechanism used to ensure data integrity during transmission. When data is sent over a network, a checksum is calculated based on the content of that data. The sender generates this checksum and sends it along with the data. Upon receiving the data, the receiver calculates the checksum again using the received data. If the two checksums match, it indicates that the data has likely not been altered during transmission.

The primary purpose of using checksums is to detect unintended changes to data. Such changes could occur due to various reasons like transmission errors, data corruption, or even interference during data transfer. If the checksums do not match, it alerts the receiver to the fact that the data may have been corrupted, and appropriate actions can be taken, such as requesting retransmission of the data.

In contrast, the other options do not align with the primary function of checksums. While file access patterns, data traffic patterns, and user login attempts may be relevant to different aspects of security and network monitoring, they do not pertain to the specific detection of data integrity issues that checksums address. Thus, checksums are focused solely on identifying unintended changes to the actual data transmitted.