Delta Transfer uses an algorithm for updating a file on one machine
to be identical to a file on another remote machine. The algorithm identifies
parts of the source file which are identical to some parts of the destination
file, and only sends those parts which cannot be matched in this way.
Effectively, the algorithm computes a set of difference without having both
files on the same machine.
Typically, Delta Transfer works very well when the two machines are
connected by a low-bandwidth, high-latency communications link. In this case,
the connection between the two machines is the major bottleneck of the whole
system. By dramatically reducing the amount of the bytes to be sent over the
link, the efficiency of the operations would be greatly improved.
Particularly, source control is the ideal application for Delta
Transfer to work extremely well. When we use source control tool, we mainly use
it to record the modifications. The similarity of the different versions of a
file is the key for Delta Transfer to perform its magic.
Note: Under the following cases, Delta Transfer may not be
very helpful:
-
When the two machines are connected by LAN. Since the LAN is a very fast
connection, the time saved by reducing the amount of bytes to be sent may not
justify the time spent on generating the delta info and reconstructing the
file.
-
If the file is in a compressed format. Since any small change in the original
file usually results in a dramatic change in the compressed file, Delta
Transfer would probably end up sending almost the whole original file plus some
bytes used by the Delta Transfer algorithm itself. The most common compressed
file formats are such as .zip, .rar, .mp3 and so on.
However, we assure you that our Delta Transfer can function
correctly, reasonably, and efficiently even under these circumstances.