Problems with symmetrical network simulation with VM

[mistahuynha]

Hello,

I am having a specific problem with simulating a symmetrical network. I have WANem running in Virtualbox VM on a host machine. On the same machine, I have an XP VM configured for bridged network settings. When I try to ping the VM with another machine (not the host), I am not getting symmetrical behavior for the RTT. I have WANem configured to delay by 50ms, but I am not getting 100ms for the RTT. When I configure the same settings, and ping from the host machine to the XP VM, I get the expected 100ms.

I tested configuring with an asymmetric network, with 50ms delays in both directions. It looks like WANem is not adding delay for the response from the outside machine to the XP VM. Any help would be appreciated. Thanks.

My Configurations:
Machine #1: 192.168.2.120

WANem VM (on Machine #1): 192.168.2.159

WANem Settings:
Symmetrical Network
50ms delay
IP source address: 192.168.2.121
IP source subnet: 255.255.255.255
IP dest address: 192.168.2.160
IP dest subnet: 255.255.255.255

XP VM Bridged Mode (on Machine #1): 192.168.2.160
route add 192.168.2.121 mask 255.255.255.255 192.168.2.159

Machine #2: 192.168.2.121
route add 192.168.2.160 mask 255.255.255.255 192.168.2.159