SIM Gateway and Asterix on Amazon Cloud

I am thinking about connecting a Dinstar sim gateway hosted locally with an Asterix instance hosted on Amazon Cloud.
Not sure whether to use a public IP or behind NAT, I would be grateful for any advice. i have done this before on a local network with out any problem, its just that because this is across the net I am concerned that there maybe security issues.

Is there any danger with open ports or from ip spoofing etc

Thanks

I’m not a networking expert, but I think NAT is more secure because your gateway won’t be exposed to the Internet, but you will need to deal with finding the correct configuration for your network to avoid any issue caused by the NAT.

exposing your Gatway to the Internet make it clear target to Dos Attacks , exploits.

Thanks for the reply, it will most likely be be given a private address.
I havent actually got one of these devices yet to play with so I would be interested if anyone has any experience using one of these devices and if there were any issues, I see in the manual there isa built in PPTP VPN service