I shall clarify my previous post. Currently JBoss Messaging (and JBoss MQ) send messages from the server to the client using an RPC mechanism. This means they send a bunch of messages then wait for a response (i.e. request/response). This means that if the network has high bandwidth, but also has high latency (think high round trip time) then for each send is going to take a minimum of 2 x latency, *irrespective* of the bandwidth. In other words it doesn't take advantage of the bandwidth. We have already seen other customers suffering from this problem. A better approach (and one we will have implemented in 1.2) is to push messages asynchrously across the network (i.e. not wait for a response). Then the throughput is not dependent on the latency. View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=3979006#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...