I don't know. We're pretty far down the road now, but there might be things that could have done with NAT/PAT to make them suck less, at least for eyeball networks. Just being the devils advocate here. What if dynamic address assignment by eyeball ISPs had been modified to allow a "fractional" IP address reservation. 1/2 IP, 1/4 IP, ..., 1/16 IP, down to maybe 1/256 IP. Each one would represent a range of ports, dividing up the available port range in 2^k pieces. This wouldn't really represent a layer of NAT, just an agreement by the CPE device to only use a specific range of ports within the assigned routable IP address (this is the fractional IP part). Of course, the upstream router could enforce that port restriction. The "low" fraction in each IP would tend to have the standard server ports available, so one server on standard ports could be accomodated per routable IP, but eyeball boxes shouldn't care that much, and everybody would have a fixed port range, so P2P services that are port flexible could still have ports to map in through. Ok, it's kind of ugly, but the PC's inside it wouldn't feel much worse off than they do today. the CPE could even map static ports all the way through to pc's on the lan... On Wed, Feb 9, 2011 at 2:44 PM, Jens Link <lists@quux.de> wrote:
Scott Helms <khelms@ispalliance.net> writes:
IPv6 for some ISPs will be extraordinarily painful because of legacy layer 2 gear
I don't feel sorry for them. We know that IPv6 is coming for how long? 15years? 10year? 5years? Well if you only read the mainstream media you should have read something about this new Internet thing about two years ago. And still many people fear IPv6 or think the can still wait for another couple of years.
For ISPs in this circumstance the choice will be CGNAT rather than IPv6 for a number of years because the cost is much lower and according to the vendors selling CGNAT solutions the impact to end users is (almost) unnoticeable.
Cost's might be lower but service will be worse. NAT breaks a lot of applications file sharing will not work properly and running your own web server at home will not work properly. Well you always get what you pay for and people will buy any crap if it is cheap enough.
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