We are about to hire some consultants to help us set up an AWS-based server environment that will enable us to handle NAT Traversal for our P2P application. One important part of the NAT Traversal infrastructure is the STUN-server (http://en.wikipedia.org/wiki/STUN).
They just told us that in order for the STUN-server to work you must have two public static IP-addresses pointing to the same server. To more specific they said this:
It appears that you need 2 static IPs for each server for the STUN to work. Please note, these IPs have to be put into the configuration file, therefore, each time you restart the instance you have to make sure you either use the same IPs or you have to update configuration.
As you plan to use AWS for your installation, please confirm that you can have 2 static IP for each server.
Our question is if this is possible using AWS and if so, how? If not, do you know any other way to set up a STUN-server using AWS?
Best Answer
As of July 2012, Amazon EC2 Instances in a VPC can be assigned one or more private IP addresses, each of which can be associated with its own Elastic IP address. A consultant such as myself working with AWS-based server environments will be able to set up your server in a "VPC" and assign "Elastic" IP addresses to meet your requirement of two static public IPs for each server. You will be charged $0.005/hour for each additional IP address beyond the first.
For more detailed information from Amazon on this, see Multiple IP Addresses