IKEv2 traffic selector support

Hi, 

I need to use IKEv2 to setup site-to-site VPN with a 3rd party, I was astonished to find that IKEv2 does not support traffic-selectors, so we will need to have multiple encryption domains between two IKEv2 gateways, how does IKEv2 address this basic requirement?

Thanks,