Remote Differential Compression
RDC is an advanced WAN-compatible compression technology that optimizes data transfers over limited-bandwidth networks. Instead of transferring similar or redundant data repeatedly, RDC accurately identifies file “deltas” and transmits only the differences to achieve bandwidth savings. This means, for example, the “deltas” caused by a simple title change in a 3 megabyte (MB) PowerPoint® presentation would take less than one second to replicate over a WAN, in contrast to one minute or more for the entire file.
RDC can also copy any roughly similar file from any client or server to another using data that is common to both computers. This effectively reduces the size of the data sent and the overall bandwidth requirements for the transfer. Local differencing techniques — sometimes called “patching” — compute the differences between two local files, detecting insertions, removals, and rearrangements of data. The differences can then be used to transform the old version to a new version. The differences between two known versions of a file are calculated on a server, and then sent to the client.
Microsoft’s internal RDC performance testing suggests that in some cases, bandwidth reduction factors may reach as high as 400:1.
|
