MTDelta

MTSYNC works pretty much like rsync and similar tools. It copies a file or a dir structure to a remote server or to a local FS. The main difference is that MTDelta is a multithreaded tool, it uses multiple streams of data to copy a file. This is specially convenient to overcome the limitations imposed by high latencies in regards to data throughput. Therefore, it will saturate whatever bandwidth you count with, regardless of the latency between the client and the remote end.

It will also greatly improve copy throughput in local file systems by using multiple cores to copy a file. It is specially designed to copy huge files, like virtual machine disks, or to sync big dir structures. Normally 4 threads will be more than enough to reach the hardware limits.

It uses a rolling delta algorithm to detect changed blocks in such way that only the differential data is copied every time. It's also zero aware, so that zeros are ignored.