During one of the sessions this week on DirectAccess, the speaker mentioned a tidbit of information which I found useful. For those of you running Windows XP and Server 2003, you know the pain of accessing file shares across the WAN. The higher the latency, the dramatically worse the performance. SMB was not designed for the WAN, so it is VERY chatty with many round trips needed to perform very basic tasks like copy a file or do directory listings.
With Windows Server 2008 and Vista, Microsoft introduced SMB 2.0 which dramatically cut down on the chattiness and thus accelerated accessing file shares across the WAN. What I learned this week is that in Server 2008 R2 and Windows 7, Microsoft made additional changes to SMB and it’s now up to revision 2.1.
In version 2.1 a command that would take 5 round trips to complete, now completes in three. And commands that took four round trips can now do it in three. While that may sound like a small change, but that’s a 25% to 40% reduction in the number of round trips. But this reduction ONLY occurs if the server and client are Windows Server 2008 R2 and Windows 7. Yet another reason to upgrade your file servers to R2 and jump on the Windows 7 bandwagon!