Use IP Multicast. It does not restrict you to LANs and is gettine more widely depoloyed everday. It used the class D address space and uses the routers in the path to maintain group memebership. In this way the server sends the data (UDP) to a single destination address and the distribution tree and packet replication is handled by the routers.
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For sending identical datasets to groups of clients, multicast is the way to go.
Use IP Multicast. It does not restrict you to LANs and is gettine more widely depoloyed everday. It used the class D address space and uses the routers in the path to maintain group memebership. In this way the server sends the data (UDP) to a single destination address and the distribution tree and packet replication is handled by the routers.