[josm-dev] IPv6 problems

[Florian Lohoff]

On Thu, Dec 31, 2015 at 02:44:59PM +0100, Dirk Stöcker wrote:
> JOSM and Java do not try different protocols. If you (and the remote
> server) have IPv6 it uses IPv6, if not IPv4.
> 
> It seems you have a broken IPv6 connection which sometimes works and
> sometimes not. You should fix it.
t
I disagree on that. The fallback to v4 should be per CONNECTION and
not per application restart. The RFCs are pretty clear on this
and further behaviour improvements on intermitted ipv6 connectivity.

JOSM is a pain in the ass concerning ipv6. I typically roam with my
notebook between dualstack and ipv4 only locations with suspend/resume
and most of the time i need to save session restart josm etc.
Its not even deterministic what the error looks like it just
complains on some random network access ...

> Trying multiple connections can hide such broken connections, but
> most applications don't do this. Web browsers are the main
> exception. JOSM not.

So you are clearly not adhearing to BCPs for dual stack application
development. There has to be a fallback to ipv4 for every single
connection attempt not just once we restart the application.

Just one of the most recent RFCs making this very clear that
intermitted ipv6 connectivity is a common case and needs to be 
worked around in the application:

https://tools.ietf.org/html/rfc6555

I used to work in the ISP Business for 15 years and applications
like JOSM are the main hinderance for ipv6 acceptance.

"It does not work when i enable ipv6" is the customer complaint
so ipv6 is kept turned off.

Flo
-- 
Florian Lohoff                                                 f at zz.de
      We need to self-defend - GnuPG/PGP enable your email today!
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