APM Policy check for access from a specific network

Hi all, I have an APM policy that I need to add a new path to. The existing route wont change, but I need to make an initial check on where the traffic is coming from. If it is from a known network or not.

 

I couldn't see a specific 'ip detection' item in the APM policy editor, so wondered if the only way to do it would be to add an iRule event and have the iRule check against a datagroup for the IP address.

 

Any info that could be provided on this would be greatly received.

 

Thanks!