Re: understanding IPv6

[Denys Fedoryshchenko <nuclearcat () nuclearcat com>]

On 2020-06-07 12:35, Daniel Sterling wrote:
> On Sun, Jun 7, 2020 at 2:00 AM Fred Baker <fredbakersba () gmail com> 
> wrote:
> > I'm sorry you have chosen to ignore documents like RFC 3315, which is 
> > where DHCP PD was first described (in 2003). It's not like anyone's 
> > hiding it.
> So while it may be true that no one is hiding this information, in my
> experience no one is shining a spot light on it either, and until I
> was told about it, I was simply unable to understand IPv6.
I can give you that easily reasons to understand it:

1 - we can avoid using virtual hosts, when you can identify things on 
L3, things become much more clear in software. Making virtual hosts in 
some protocols are living hell.
2 - P2P communications are possible again.
2.1 As soon as you need to access ANYTHING at your home, your choice 
only begging ISP for one real IP(most often dynamic), then you struggle 
with port forwarding stuff. With IPv6 it gets really simple.
2.2 Direct P2P file transfers from friend to a friend, you don't need 
cloud services anymore and/or headache with NAT pinning and etc
2.3 Gaming
2.4 Some industrial equipment really love P2P VPN, with IPv4 they are 
forced to use some "middle point" in "cloud", that decrease reliability, 
increase latency and most important jack up operational costs and 
require continuous support of this "middle point".
3 - As user can be easily identified, no more "captcha" stuff or 
struggling with NAT pool IP bans (very painful with gaming services, 
twitter, google).
4 - Dealing with LEA requests is much easier and cheaper

There are very interesting and unobvious moments on IPv4 vs IPv6, for 
example related to battery lifetime in embedded electronics. In ipv4, 
many devices are forced to send "keepalives" so that the NAT entry does 
not disappear, with IPv6 it is not required and bidirectional 
communications possible at any time. And in fact, it has a huge impact 
on the cost and battery life of IoT devices.
When I developed some IoT devices for clients, it turned out that if 
"IPv6-only" is possible, this significantly reduces the cost of the 
solution and simplify setup.

But there is one huge minus. We cannot switch to ipv6 completely and are 
forced to bear the costs of ipv4 too.
In addition, many services (like Sony playstation stuff) continue to ban 
ipv4 address, and doesn't bother themself to implement ipv6 (which is 
supreme stupidity and technical idiocy).