linux - How can I verify that a 1TB file transferred correctly?

I frequently transfer VM images from hypervisors to an archive server for long term storage.

I transfer using netcat since it is faster than scp, rsync, ect..

hypervisor$ cat foo.box | nc  1234

archive$ nc -l -p 1234 > foo.box

When the file has finished transferring, I verify there was no corruption by running md5sum on both the target and source.

Unfortunately, running a md5sum on a large file can take a very long time. How can I more quickly compare the integrity of two large files?

Update:

• My transmission rarely gets interrupted so restart-ability is not an issue.


• It generally takes 3-4 hours to transfer via NC and then 40 minutes to get the md5sum.


• The security of the hash is not an issue in this case.