Sometimes, you do not have access to enough public address space to number all your subnets. This is especially recurrent in virtualized environments where network segmentation is a natural design choice. In such environments, you may have several VLANs and routing instances (call them routing domains, or contexts, depending of the vendor terminology you're familiar with), and for each, comes a unique set of subnets. Every network operator knows how painful IP address management is, and we all want to avoid renumbering our network, especially if the following account for hundreds, if not thousands of subnets. You certainly also figured out that Network Address Translation (NAT) could help in this manner, but do you know its benefits could be as well applied to the IPv6 world?