I have an application in mind where I would like to send the same data (5MB - 50MB) to a number of clients over the internet. Since the server connection to the Internet has limited bandwith (512K uplink) and there could be up to 100 clients wanting the same info, I was wondering if there is a more efficient method than direct sends to each client.

1) I'm thinking of a method similar to sending an email to a distribution list, ie. done with a single send.
Is it possible over TCP/IP using VB6 and Winsock (or Winsock API)?
Is it possible to imbed a number of IP addresses into the IP datagram?
Is there anyother way of achieving something like this over the Internet? (Multicast of some sort?)

2) If the clients were logged onto the server via VPN or something, would a Multicast work then?


Cheers,
Nap