We have 2 MPLS PE nodes(Cisco 7600). The Server1 is connected on PE1 and Server 2 is connected on PE2.We have a latency of around 20 ms between these two PE nodes. When we tried to do data transfer from Server 1 to Server 2 by means of FTP,we could acheive some were around 20Mbps has peak utilization for that FTP session. Then we understood the BDP(Bandwidth delay product) comes into issue and the throughput depends on the latency. So inorder to increase the throughput,we try to increase the server 1 and server 2 window buffer sizes to more than 64Kbytes,but we couldn't see much differnce in the throughput.
Meanwhile we are tring to understand the ip tcp window-size command on the PE router and does this has any relation to the above scenario.Also what this command really does for the router and if it is not set,whats the default value on it.Any help would be really appreciated.
Also, when we increased the buffer sizes from 32k to 64k ,there are significant increase in the throughput but not when we increased above 64k.
Anantha Subramanian Natarajan