Re: understanding IPv6

[Etienne-Victor Depasquale <edepa () ieee org>]

What I'm amazed at is the concept of multi-link subnet and the change in IP
model being proposed.

See, for example, section 4 of
https://tools.ietf.org/html/draft-thubert-6man-ipv6-over-wireless-05

Has anyone felt the same about the change being proposed? This swept away
25 years of thinking about IP subnets and IP links for me.

Etienne

On Sun, Jun 7, 2020 at 6:03 PM Brandon Martin <lists.nanog () monmotha net>
wrote:

> On 6/7/20 6:01 AM, Denys Fedoryshchenko wrote:
> > 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.
>
> This is difficult to understate.  "People" are continually amazed when I
> show them that I can leave TCP sessions up for days at a time (with
> properly configured endpoints) with absolutely zero keepalive traffic
> being exchanged.
>
> As amusingly useful as this may be, it pales in comparison to the
> ability to do the same on deeply embedded devices running off small
> primary cell batteries.  I've got an industrial sensor network product
> where the device poll interval is upwards of 10 minutes, and even then
> it only turns on its receiver.  The transmitter only gets lit up about
> once a day for a "yes I'm still here" notification unless it has
> something else to say.
>
> In the end, we made it work across IPv4 by inserting an application
> level gateway.  We just couldn't get reliable, transparent IPv6
> full-prefix connectivity from any of the cellular telematics providers
> at the time.  I don't know if this has changed.  For our application,
> this was fine, but for mixed vendor "IoT" devices, it would probably not
> work out well.
> --
> Brandon Martin


-- 
Ing. Etienne-Victor Depasquale
Assistant Lecturer
Department of Communications & Computer Engineering
Faculty of Information & Communication Technology
University of Malta
Web. https://www.um.edu.mt/profile/etiennedepasquale