Fujitsu Laboratories has developed a software-based technology to increase data-transfer speeds for accessing files on remote enterprise file-sharing servers. When accessing remote file-sharing servers in the cloud, slow upload and download speeds for typical file-sharing systems due to network latency has been an issue.

The problem is the nature of the CIFS and SMB file-sharing protocols, which are widely used in file-sharing systems.

When copying a folder containing a large number of files, all of the file-attribute information is requested for each file, and the accumulation of these requests in a remote network causes significant latency.

In addition, when sending relatively large files, their data is split into pieces tens of kilobytes in size, and header information is attached to each data. Because this header information is updated each time, the transmitted data becomes different even if it sends the same file, which makes deduplication ineffective.

Fujitsu says that by using its newly developed software that relays communications between the client and server, the number of communications made has been significantly reduced, lowering the effects of network latency. This communication frequency occurs when obtaining information on multiple file names and file sizes on a remote network. In an internal experiment, file transfers were confirmed to be up to ten times faster when dealing with multiple small files. Transfers of large files can be up to twenty times faster when combined with the deduplication technology Fujitsu Laboratories announced last year. Deduplication and compression reduce the volume of data being ransmitted, effectively increasing data-transmission speeds.

Fujitsu's technology is implemented as software and can be installed on existing file-sharing systems. It can also be applied to cloud and server-virtualization environments, mobile devices, etc., and can be extended to a variety of network services.

Fujitsu Laboratories plans to implement this technology into a product as a function for a WAN optimization solution during fiscal 2015.

Howe it works

The new technology uses a module installed on both the client and server that accelerates data transfers. The server-side module: 1) identifies when a folder containing multiple files starts to download; 2) read-ahead on the client proxy the batch of all the files downloaded; 3) these read-ahead files are bundled together and transmitted to the client-side module; and 4) the client-side module then replies to a request to get data with its server proxy.

In this way, the amount of communications generated by obtaining file attributes, such as multiple file names and file sizes, is greatly reduced, as are the delays influenced by network latency.

Fujitsu developed a technology that works on the server-side module to separate the transmitted data into the headers and the contents of file. This makes deduplication of retransmitted data more precise, leading to more effective network traffic reduction.