[linux-cifs-client] NetBIOS Session Service question

[kewlemer]

Folks,

I'm new to CIFS and have been reading Chris Hertel's book and
simultaneously playing around with my Samba server on FC6 box. I have
here a basic question on CIFS.

I tested my Samba server from Linux and XP clients. From the captures
I found that linux used port 139 with NBT and XP used port 445 with
raw transport.

In both cases, I found that there is "NetBIOS Session  Service" data
(with type always set to Session Message) that comes up in all the
packets from the SMB Negotiate Protocol Request onwards. I can
understand that this is needed in case of NBT since it uses NetBIOS.
But can anyone tell me why I see these "NetBIOS Session  Service" data
in case of raw transport SMB packets ?

Thanks in advance,
KM