Folks
I have been following the IPV6 comments.
What concerns me with the loss of NAT are the following issues:
1) My friend from half-way around the world comes to visit. He turns on his IPV6 enabled device (think Ipad), and wants to use my ISP's connection. What IP address does he get? If it's his home address, that makes routing difficult. If he dynamically gets one of "my" addresses a) Did my ISP give me enough? b) Do I get charged by my ISP on a per-device basis?
2) Today, my ISP doesn't know (or doesn't care) how many devices I have in my home -- my Linux gateay with DHCP and NAT hides all of that. With IPV6, what is to prevent my ISP from charging me a per-device fee?
3) When I connect my IPV6 refrigerator with its automatic inventory system tracking every RFID-enabled carrot I use, won't I be making my shopping habits visible to all those annoying advertisers? Or, in other words, am I compromising my privacy? Actually, although such dissemination of information can be blocked by a correctly designed firewall, I suspect the "Free IPv6 DSL Modem and Router, Sponsored by <your-favorite-commercial-site>" that comes with your ISP contract, would err on the side of promiscuity.
Concerned Linux/Windows/Mac/Wii/Iphone/Ipod/Ipad/Xbox user
David