On Mon, Mar 10, 2003 at 06:04:02PM -0500, Bound, Jim wrote: > > For edification. I have a node on a work LAN that knows nothing of > IPv6. I download software and configure my node to be capable of IPv6. > I manually configure my interface to support IPv6. I now ftp to an IPv6 > address. This is not going to work. But I was stupid to think it > would? Is this the kind of basic mistake your also worried about?
Agreed if you're static in a network, then that's a mistake. But a common problem is taking an IPv6-enabled device from a "dual stack" network where it happily runs using either protocol into one where only IPv4 is supported. Then what happens varies with OS/browser. For example, in WinXP+MSIE6 any attempt to reach a site with an AAAA (and A) record will fail with an error after 20-60 seconds. With WinXP+Mozilla 1.3 a similar attempt will just get an immediate "connection refused". In neither case is there (the desirable) fallback to IPv4. So for people who want to go dual-stack in their workplace yet take devices to IPv4-only networks that's the problem they face. Of course you get what you deserve maybe for the application writer trusting presence of a DNS record as an indication of connectivity. There will be some user-land settings required for IPv6 connectivity. For example RFC3041 needs to be per application so you can rely on (as many people will want to) per-host IP-based authentication for ssh access, while taking advantage of RFC3041 while browsing the net from the same host. I can see that we can offer users a privacy/fixed IP toggle, and many could understand that as an advanced setting in their TCP/IP options, but it's something we want to shield "typical" users from. I don't believe a userland v4/v6 toggle would be useful for "typical" users. It be used by the v6-geeks in the current stage of deployment, but we need more robust methods for handling movement between dual-stack and IPv4-only networks where IPv6 is enabled on a device. We're paying for the choice of app developers to promote IPv6 by trying IPv6 ahead of IPv4, and then not falling back (quickly) when it fails. Tim -------------------------------------------------------------------- IETF IPng Working Group Mailing List IPng Home Page: http://playground.sun.com/ipng FTP archive: ftp://playground.sun.com/pub/ipng Direct all administrative requests to [EMAIL PROTECTED] --------------------------------------------------------------------
