How does the update function of antiviruses work?

Question

Java

Interesting mechanism of work updates. I assume that the client has a file with the date of the next update. And the program has a timer that, when the time comes, makes a request to the server and downloads updates.

Answer 1

in such tasks, you must first determine more precisely what is required, for example, if the volume of all files is 3 mb, then it makes no sense to even bother, if the volume is under 10 GB and the files are 300 mb each and any of them can change, then md5 is also not an option, because you have to transfer every time anew