Double network bandwidth consumption than rostopic bw! ROS1 with VPN

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Hi

I see expected network bandwidth consumption on physical private LAN. But I see double network bandwidth consumption with a VPN (globalprotect). The VPN is being used to connect nodes through internet. I attach a snap below: Is there anyone observing the same issue? Any solution? (Sorry if it is a VPN specific issue)

Master:
export ROS_IP=10.72.111.47
export ROS_MASTER_URI=http://10.72.111.47:11311
(e.g.) rosrun image_publisher image_publisher /opt/ros/noetic/share/rviz/images/splash.png


Slave
export ROS_IP=10.72.111.59
export ROS_MASTER_URI=http://10.72.111.47:11311