[Slightly OT?] Performance of SMB over WANs

[Jason Haar]

We've got a knarly issue here, and I'm wondering if anyone here could help
me understand it.

Our company's WAN runs primarily over IPSec VPNs. Benchmarking shows
Linux-to-Linux FTP/HTTP peaks at around 80% of the available Internet link
over which the VPN operates - so that's looking pretty sweet.

However, Microsoft networking runs at ***1/10th*** that amount! i.e. SMB
transfers are a fraction of FTP transfer rates. 

I originally thought this was a M$ stack issue, but then brought Samba in
and benchmarked it on the same two Linux boxes used for the FTP tests - they
had the same poor throughput.

So, can anyone explain to me what's so different about SMB that would so
radically affect it over a WAN link? I would have thought that after the
initial auth/perms checks are done, the streaming of the data would approach
FTP speeds...

BTW, RH7.x Linux systems, transmitting 6Mb files.

-- 
Cheers

Jason Haar

Information Security Manager
Trimble Navigation Ltd.
Phone: +64 3 9635 377 Fax: +64 3 9635 417