= Сообщение: 4473 из 7440 ============================================= IPV6 = От : Michiel van der Vlist 2:280/5555 15 May 17 00:31:57 Кому : Tommi Koivula 15 May 17 00:31:57 Тема : DS-Lite emulation experiment FGHI : area://IPV6?msgid=2:280/5555+5918db5e На : area://IPV6?msgid=2:221/360+59189580 = Кодировка сообщения определена как: CP850 ================================== Ответ: area://IPV6?msgid=2933.fido-ipv6@3:633/410+1d7ed11f ============================================================================== Hello Tommi,
On Sunday May 14 2017 20:36, you wrote to me:
TK> We are waiting for the results of the experiment. ;)
As published in Fidonews:
================================================================= GENERAL ARTICLES =================================================================
A DS-Lite emulation experiment By Michiel van der Vlist (2:280/5555)
Presently I have a native dual stack connection from my ISP. So I have both public IPv4 and IPv6 addresses for my binkp server. This luxury may not last forever. The IPv4 address pool has been depleted and so ISPs are starting to put new customers on so called DS-Lite. This means customers will have fully functional IPv6 but they will not have a public IPv4 address. For IPv4 they will be behind a Carrier Grade NAT or GCNAT. A CGNAT is basically the same as the NAT running in your home network, with the difference that it is run by the ISP, and the customer has no access to the port forwarding tables. And so they can not accept incoming calls on IPv4.
DS-Lite will not stop at new customers. It is foreseeable that existing customers will be affected too. I would not be surprised if my ISP puts me on DS-Lite between now and five years and that the alternatives will be economically unattractive.
To be prepaired I ran some experiments to test if it would be doable to run a Fidonet node from a DS-Lite connection. Presently there are two nodes in the nodelist that carry the INO4 flag, indicating that they can not accept incoming IPv4 connects. But these are not the only node of the listed sysop. They have at least one other node listed that can accept incoming IPv4. I wanted to test if it is doable if the node is the only listed node of the sysop in question.
With 50+ registered IPv6 capable nodes, I think the Fido IPv6 club has gained critical mass and so running a DS-Lite node would be doable But of course the proof of the pudding is in the eating.
So I did two tests. The first test was a seven hour run on Saturday May 6th 2017 from 11:00 UTC until 18:00 UTC.
I did this:
o I configured my binkp server to only listen on IPv6. ( listen [::] in binkd.cfg )
o I polled every IPv4 only node with whom I had a password protected link every 30 minutes.
The result of this test was encouraging. Only one sysop asked me why I polled his system every 30 minutes, the rest of Fidonet did not seem to have noticed anything at all. I did not seem to have missed any mail either.
The second test was a 24 hour run from Friday May 12 12:00 UTC until Saturday May 13 2017, 12:00 UTC. On Tommi Koivula's suggestion I also removed the A record for my nodelisted host name.
The result was the same as for test #1. Nobody complained and no mail was lost. The preliminary conclusion is that running a Fidonet node from a DS-Lite connection is doable.
There was one thing that was a bit problematic though. When I am on the move, I run a point system on my laptop to keep in touch with Fdionet. This won't work when I am on an IPv4 only network since I can not connect with my IPv6 Boss Node from there. Most public WiFi networks on campings and hotels are still IPv4 only. And so are nearly all 3G/4G mobile operators in Europe I am afraid.
Running a SixXs AYIYA tunnel on my laptop would have solved that problem, but alas, SixXs is closing down in less than four weeks, so that won't be the solution. Then Tommi Koivula half jokingly suggested I try Teredo. I thought Microsoft had switched off the Teredo relays and servers many years ago, but to my suprise they are still there.
It so happened that I spend a few days on a camping in Belgium last week. The Wifi there was brand new. Excellent coverage and reasonable speed. Alas, no IPv6. So a perfect opportunity to test if I could reach my IPv6 binkp server at home using Teredo. So I first enabled Teredo. From the command line in a window with administrator rights: (Windows 7)
netsh interface teredo set state client
To make it work properly I also had to disable isatap:
netsh interface isatap set state disabled
The Teredo tunnel was slow and I got lots of timeouts but it was just good enough for a Fidonet connection between a point and his boss.
Then when I came back home, I tried the same by making a connection via my FON spot. The FON spot is IPv4 only, so that looked like a good way to test the connection. It did not work. The diffenerence between the FON spot and the WiFi on the camping is that the FON spot is a cascaded NAT. Teredo apparently does not work from beheind a double NAT.
It is no big deal. I probably have some more time to find a solution for this and the test was if it is doable to run a DS-Lite node in the network, not if it can support mobile points or users.
Conclusion: Running a Fidonet node from a DS-Lite connection is doable It is not perfect, Dual Stack is still preferable, but as the number o IPv6 capable nodes rises, it will get better and it is not worth to invest lots of money for additional incoming IPv4 capability.
I hope this will inspire others to do similar tests.
(C) Michiel van der Vlist, all rights reserved. Permission to publish in the FIDONEWS file echo, the FIDONEWS dis- cussion echo and the FNEWS_PUBLISH echo as originating from 2:2/2.
