IPsec and iOS

[Deftone]

I'm using IPsec in combination with my iPhone. It's working like charm except one thing. When I lay my iPhone down for a few minutes (1 minute after the screen turns black) the VPN connection goes down. I need to turn on the VPN connection evry time I wake up my iPhone. Is there something I can change so that my iPhone keeps VPN connected? 

[Kangming]

Here is a link explaining this situation:

https://www.sparklabs.com/support/kb/article/why-do-my-vpn-connections-disconnect-on-sleep/