Hi,

I've been using md5sum to verify the transfer of a file from one server to another. Basically, I take the md5sum on the source server and compare it against the destination server.

Recently, I saw there were other methods to do this 'verification' by using cksum and sha1sum.

Below are some benchmark timings that I've done on a 1.5 GB file:
md5sum - 8.4 sec.
cksum - 8.0 sec.
sha1sum - 14.7 sec.

Correct me if I'm wrong for the following assumptions:
1. All of the checksumming methods are CPU intensive. Would anyone know which is the most CPU intensive?
2. md5sum is the more preferred method (not sure why).

So, if I only want to do a quick checksum, then can I use cksum? Or is there a faster but less reliable method to do checksum?

Thanks in advance.

...or could it be sha1sum just isn't widely accepted yet as a replacement?


Between two servers you control? Sure, what you want.


If hash comparison is done to confirm reliable transfer then why would you be looking for something less reliable?

Hi,

The algorithm for 'md5sum' is theoretically the best suited for the security of exchanging files/images such as an 'ISO' or other large files. By the use of the 'md5sum' we can transfer large files without the worry of corruption. Meaning if we have the sum then we compare our received file with the original sum then there is no need to have the original image to compare too. We just use the original sum to compare with. This method does prevent someone from corrupting the original form since it would be impossible to create the same sum as the original.

As for comparison to other hash code methods. I leave that too you as a LQ or Google search then discern the information to close the thread.

from: http://en.wikipedia.org/wiki/Sha1sum

And from: http://en.wikipedia.org/wiki/Md5sum