Lorenzo Colitti wrote:
IPv6 will be ignored, because IPv6 is, technically, useless, which has nothing to do with IPv6 address allocation policy.
Because IPv4 NAT can be fully transparent end to end, it's fine to use port restricted IPv4 with NAT.
Well, but there are lots of things you can't do with port restricted IPv4 and NAT.
FYI, I'm not talking about A+P, which is a combination of port restricted IP and poor legacy NAT with no end to end transparency. I'm talking about port restricted IP with full end to end transparency for all the applications including skype. See <draft-ohta-e2e-nat-00.txt> how all the applications, including ftp port command and skype, works as is. An implementation is already running.
For example, run a peer-to-peer program with 1000 simultaneous connections.
As a transport connection is identified by both source and destinaiton port numbers, you only need a single port to have 1000 simultaneous connections with 1000 other hosts.
Run itunes and Google maps on or your computer, your girlfriend's computer, and your phone at the same time.
It's trivially easy. Problems caused by improperly behaving applications should be solved by the improperly behaving applications. That's all.
On the server side, IP address sharing on a large scale means lack of geolocation, and lack of geolocation means no location-aware services.
If you want to destroy location privacy, you should better forbid ISPs use PPPoE, which destroys detailed geolocation already today. As there will be no port-wise routers at the backbone (there is no routing protocol to support port wise routing), hosts sharing an IP address are assured to be confined in small geographical area, unless you do yet another tunneling such as PPPoE.
Better hope your IP address neighbors aren't sending it too many queries, because otherwise the website operator might block your IP address for excessive use.
That's no different from the situation today with DHCP assigned /24 or /16 shared by you and your neighbours. Still, it is a lot better than using IPv6, with which you can hardly reach any web site.
Without IPv6, there will be more and more pressure on port space as user numbers continue to grow, so these problems are likely to get worse and worse.
So far, there is no problem of port restricted IP exist.
As someone who has designed and operated IPv6 networks, I can say it's not more complex,
You shouldn't
But of course, if you already know how IPv4 works and you don't want to learn anything new it will seem complex.
As a person who changed IPv6 address structure from 10+6 to 8+8, trying to make IPv6 a little better than the worst, I know very well how IPv6 fails to work. If you don't want to learn anything new from your experience, it's your problem. Masataka Ohta