I have seen how to throttle the BW used by the clients from within IIS.  Will this also throttle the servers bandwidth when it updates it's signature files?

The problem we are having is that we use VoIP in our office, and the server appears to be on a 4 hour interval to update it's signature files.  When it starts to download the updates, it saturates our T1 and any telephone calls occuring at that time get dropped.

I've gone through the forums and literature, and I can't find information on how to:

1.  Limit bandwidth used by the server when downloading signature files [not the clients, but the server itself], or;
2.  To designate a time schedule when the server will download the files, so it is done after business hours, or;
3.  Be able to designate a particular NIC on the server used to download the signature files, so I can throttle that port on the managed switch and prevent the server from saturating the T1 while downloading signatures.

We currently have to throttle the switch port connected to the firewall so the servers download bandwidth [and subsequently the entire office internet connection] is held below full capacity of our T1.

We have been in contact with our ISP to resolve the problem through QOS settings on the router, but that's another avenue.

Thanks,
Tom