Re: [SPF:fail] Re: possible bad ipv6 mirror [partial solution]

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



On Sat, 2010-01-16 at 16:49 +0800, Ed Greshko wrote:
> My ISP is a pure IPv4 ISP.  My ADSL modem doesn't know a thing about
> IPv6.  Yet....
> 
> [egreshko@f12 ~]$ ping6 2001:4860:c004::68

I haven't done anything more than a quick check recently, but my ISP
*didn't* support IPv6, hasn't made any announcements about supporting it
that I can recall, nor does any other ISP I know of (bar one), nor does
any domestic networking hardware that I know of support it (here in
Australia).

My ADSL router/modem is a standalone device, I don't use it as a raw
modem (relying on a computer, behind it, to do all the authentication
and routing), *it* has to be able to handle whatever I try to put
through it.  And that is how I want to run my network.

On the computer I haven't deliberately disabled IPv6:
$ ping6 2001:4860:c004::68
connect: Network is unreachable

On the computer I deliberately disabled IPv6:
$ ping6 2001:4860:c004::68
socket: Address family not supported by protocol

Both do exactly what I expect them to.  The same sort of error as I'd
expect if I'd tried to do something with an unreachable IPv4 address on
my network.

The only way IPv6 can be used, is if there is a working IPv6 network
between you and them, or you have something acting as your proxy
bridging the gap.  That proxy has to be somewhere where it *can* bridge
the gap.  It's no good putting one where it's still isolated.  And what
happens when someone wants to connect back to you at your IPv6 address?

Proxying/tunnelling are semantics for the same thing - doing one through
the other, but neither is direct.  I view having to use a tunnel as
being just about as bad as having to use NAT, and some of the IPv6 to
IPv4 conversions are virtually the same as NAT (making at least one use
of IPv6 pretty pointless, as IPv6 is one solution to avoid having to use
NAT with IPv4).  Leaving us with yet another mess to have to deal with,
instead of just doing things directly (i.e. IPv6 on my MODEM/router and
ISP).

Simply finding the IPv4 address from the dual addresses for something
that has both v4 and v6 isn't using IPv6, at all.  And for a lot of
people (probably including those who think IPv6 is working for them),
that's all that they'll be doing.  For instance, mplayer will do that
when you try to connect to a stream over the net, first it'll try IPv6,
then it'll fallback to IPv4.  In some cases, there's an annoying delay
before the fallback.  Or no fallback, as it finds an address, but simply
can't connect to it, and aborts trying anything else.

Before someone gives me it in the neck.  I do see the point of view that
it's a solution looking for a problem, but the problem does exist (IPv4
address exhaustion), it's just *when* it will be a problem is still
debatable.  And it would be good to get it working ahead of time.  But
this is not helped by manufacturers who continue to produce IPv4-only
equipment (many years after we knew of this situation), and sell no
additional/alternative IPv6 domestic equipment, making it next to
impossible for all but true geeks to use IPv6.

I see v6 bringing a myriad of its own problems, the chief ones being
firewalling and address assignment.  Many of us are quite familiar at
defining the division between WAN and LAN with IPv4, so we can control
our network.  I've seen a dearth of clearly coherent information about
the same sort of thing with IPv6, so I expect an awful lot of security
problems down to network boundaries and firewall rule errors when it
becomes available to the great unwashed.  Many of whom, currently,
unwittingly rely on NAT /breaking/ networking to provide some insecure
isolation from the rest of the world.  But will, then, have to set up
dual rules (you'll need to have separate rules for IPv4 and IPv6
addresses, if you want to firewall things).  And I wonder whether
Windows will spend years repeating the mistakes it's done in the past,
such as sharing out your LAN to all and sundry, by default.

Not to mention the fun and games we'll have to go through to learn how
to manage our own networks (address assignment; name resolution; having
consistent name resolution when your assigned IPv6 address may be
variable and assigned by something with little, or no,
user-configuration possible; DHCP configuration, etc., etc., etc.).  And
there'll probably some price gouging by webhosts and domain registrars
for you to have an IPv6 address as well as your IPv4 one.

I'd make an educated guess that our ISPs are avoiding implementing it
because they want to avoid the additional work to do so.  Not to mention
having to replace equipment that simply can't support it.

-- 
[tim@localhost ~]$ uname -r
2.6.27.25-78.2.56.fc9.i686

Don't send private replies to my address, the mailbox is ignored.  I
read messages from the public lists.





-- 
users mailing list
users@xxxxxxxxxxxxxxxxxxxxxxx
To unsubscribe: https://admin.fedoraproject.org/mailman/listinfo/users
Guidelines: http://fedoraproject.org/wiki/Communicate/MailingListGuidelines
[Index of Archives]     [Older Fedora Users]     [Fedora Announce]     [Fedora Package Announce]     [EPEL Announce]     [Fedora Magazine]     [Fedora News]     [Fedora Summer Coding]     [Fedora Laptop]     [Fedora Cloud]     [Fedora Advisory Board]     [Fedora Education]     [Fedora Security]     [Fedora Scitech]     [Fedora Robotics]     [Fedora Maintainers]     [Fedora Infrastructure]     [Fedora Websites]     [Anaconda Devel]     [Fedora Devel Java]     [Fedora Legacy]     [Fedora Desktop]     [Fedora Fonts]     [ATA RAID]     [Fedora Marketing]     [Fedora Management Tools]     [Fedora Mentors]     [SSH]     [Fedora Package Review]     [Fedora R Devel]     [Fedora PHP Devel]     [Kickstart]     [Fedora Music]     [Fedora Packaging]     [Centos]     [Fedora SELinux]     [Fedora Legal]     [Fedora Kernel]     [Fedora OCaml]     [Coolkey]     [Virtualization Tools]     [ET Management Tools]     [Yum Users]     [Tux]     [Yosemite News]     [Gnome Users]     [KDE Users]     [Fedora Art]     [Fedora Docs]     [Asterisk PBX]     [Fedora Sparc]     [Fedora Universal Network Connector]     [Libvirt Users]     [Fedora ARM]

  Powered by Linux