[Samba] Fundamental question about the SMB protocol

[Hall, Ken (ECSS)]

I realize this may seem like a lame question, but I'm not an expert on the SMB/CIFS protocol, so I'd be very grateful if someone could help me.

We're considering putting a Samba server on a Linux/390 system, but the new networking mechanism under IBM's VM OS doesn't support multicasting yet.  I understand that the SMB/CIFS protocol depends,
at least partially, on multicasting, so I'm wondering if what I want to do is even possible.

Is it possible to use Samba on a LAN that doesn't support multicast?  If so, what capabilities would be lost?  The clients would be on the other side of a router-type system.

Thanks much.