I am trying to find out information about user data use while they are on the VPN.

[MatthewFletcher]

We had a user that had a mifi data usage bill that was very high. They claim that all they used it for was to VPN into the PA, and then RDP to a local pc. The PA said their internal data usage was low. The user said once they had VPN'ed into the network, they would leave the VPN open for hours. 

So would the data usage of this user's VPN connection show up as the data usage displayed in a user report? To put it another way, if user A, used a MIFI to VPN into the PA and did nothing else, and his data usage on the MIF said 1gig, would the PA show approximately 1 gig worth of data usage, because it includes the data from the VPN tunnel

[jdelio]

any extra traffic (vpn tunnel negotiation,etc.) should be negligible.  

Traffic in the logs should show the traffic from the client , If the rule if configured correctly.  

So, Either:

1. There could be a rule allowing and not logging the traffic.. 

2. Traffic from the client is going somewhere else (not across the VPN tunnel)