Windows Server 2008 R2 - Server Message Block 2.0

Introduced in Windows Vista and Windows Server 2008 is Server Message Block 2.0, more commonly called SMB2. SMB2 is a protocol that handles the transfer of files between systems. Effectively, SMB2 compresses file communications and, through a larger communications buffer, is able to reduce the number of round-trips needed when transmitting data between systems. For the old-timers reading this chapter, it is analogous to the difference between the copy command and the xcopy command in DOS. The copy command reads, writes, reads, writes information. The xcopy command reads, reads, reads information and then writes, writes, writes the information. Because more information is read into a buffer and transferred in bulk, the information is transmitted significantly faster. Most users on a high-speed local area network (LAN) won’t notice the improvements when opening and saving files out of something like Microsoft Office against a Windows Server 2008/2008 R2 server; however, for users who might be copying up large image files or data sets between systems will find the information copying 10 to 30 times faster. The performance improvement is very noticeable in wide area network (WAN) situations on networks with high latency. Because a typical transfer of files requires short read and write segments of data, a file could take minutes to transfer across a WAN that can transfer in seconds between SMB2-connected systems because the round-trip chatter is drastically reduced. For SMB2 to work effectively, the systems on both ends need to be Windows Server 2008/2008 R2 systems, Windows Vista or Windows 7 systems, or a combination of the two. A Windows XP client to a Windows Server 2008/2008 R2 server will communicate over SMB 1.0 for backward compatibility and will not gain from this new technology.

Source of Information : Sams - Windows Server 2008 R2 Unleashed