VPN is now the ultimate solution to most if not all organizations to allow simpler work environment, further work flexibility, saving cost, and yet still perform the needed work remotely. But, as its with any technology. Security is still the concern. VPN is no different, it has its sweet benefits yet further security challenges. Read through this resource:

https://learningnetwork.cisco.com/docs/DOC-15048
and thought of sharing it to get your insights also as how you are handling the security of your VPN? what is more challenging, is it the choice of technology, cost, and/or the implementation & maintaining the technology chosen?

Thanks

Mansour Sharha