Re: 6to4 question

[Michael Banta]

It is a linux router running MDK10.1.  It is a cable connection with a 
static ip.  Dayton, OH.

I am soo close!  Just can't get there.
Thanks
Bound, Jim wrote:
thats cool.  What router is that?  Are you on xDSL or Cable? What
geography?
this is a good list and good discussion for sure.
thanks
/jim 

 

-----Original Message-----
From: Michael Banta [mailto:[EMAIL PROTECTED] 
Sent: Thursday, March 17, 2005 6:09 PM
To: Bound, Jim
Cc: users@ipv6.org
Subject: Re: 6to4 question

I have protocol 41 allowed to pass on my router.
Bound, Jim wrote:
   

Thats where Teredo can help otherwise you need to be able to 
     

get inside
   

your router to permit protocol 41 and encap Ipv6, which some 
     

hard core
   

operator type engineers I know have done.  This is a huge problem for
many. It basically is a bummer.
/jim 


     

-----Original Message-----
From: Michael Banta [mailto:[EMAIL PROTECTED] 
Sent: Thursday, March 17, 2005 12:57 PM
To: Bound, Jim; users@ipv6.org
Subject: Re: 6to4 question

I don't know.  My linux router works fine, say going to 
       

kame.net, or 
   

pinging it via ipv6.  Not sure how to handle my inside behind 
a firewall 
with nat clients having private ips (10.0.10.x).

Bound, Jim wrote:
  

       

If you have a valid IPv6 prefix why use 6to4 addreses at 
    

         

all?  Why not
  

       

just deprecate 6to4 and move to IPv6 addresses directly?
thanks
/jim 


    

         

-----Original Message-----
From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On 
Behalf Of Fredrik Tolf
Sent: Wednesday, March 16, 2005 6:38 AM
To: Michael Banta
Cc: [EMAIL PROTECTED]; users@ipv6.org
Subject: Re: 6to4 question

On Wed, 2005-03-16 at 04:41 -0500, Michael Banta wrote:
 

      

           

I am aware of a full ip address, just figured I would spare 
   

        

             

you the full 
 

      

           

address since it is not pertenant to the question.
I keep reading that with 6to4 addresses, they are supposed 
   

        

             

to start with 
 

      

           

2002: prefixes so that autoconfiguration can take place 
   

        

             

with the clients.
6to4 address are something quite different from a block 
provided through
a tunnel. a 2001 address is a "real" IPv6 address -- that is, 
a part of
the IPv6 Internet with no IPv4 dependencies.

6to4 addresses (i.e. those starting with 2002), on the 
      

           

other hand, are
  

       

part of the IPv4-to-IPv6 migration plan. If you have a globally
aggregatable IPv4 address (i.e. an IPv4 address that anyone 
on the IPv4
internet can send packets to, such as _not_ a part of the 
192.168.0.0/24
blocks), you are, with 6to4, automatically given a /48 
           

IPv6 subnet.
   

I know I haven't really explained this very well at this 
point, so I'll
try with an example. I'm using 6to4. I have a static IPv4 address,
82.182.133.20. Written in hexadecimal, that is 52.b6.85.14. 
Using that,
I can construct my automatic 6to4 subnet: 
2002:52b6:8414::/48. I, too am
using a Linux router with radvd, and the computer I'm 
      

           

typing this from
  

       

has gotten the 
      

           

address2002:52b6:8514:200:20c:76ff:fe3b:a3f4. The nice
  

       

thing with this is that I need no tunnel provider. The bad 
thing is, of
course, that it depends on IPv4.

The way 6to4 works is that when my router detects an outgoing IPv6
packet, it first checks the destination address. If it starts 
with 2002,
it rolls the packet inside an IPv4 packet, checks bits 16 
through 48 in
the destination address, and put those in the IPv4 
      

           

destination address
  

       

field. For example, when communicating with my friend, 
           

who also uses
   

6to4 and has the IPv4 address 213.132.111.101, I send a 
      

           

packet to her
  

       

IPv6 address, 2002:d584:6f65::1. My router extracts 
d584:6f65, which is
213.132.111.101 in hexadecimal, and puts that in the IPv4 packet's
destination address field, puts the IPv6 packet as the IPv4 
payload, and
sends the packet. When her computer picks it up, it 
           

unwraps the IPv6
   

packet and uses it.
When communicating with a non-6to4 address, my router sends 
      

           

it, again
  

       

wrapped in an IPv4 packet, to a IPv4-to-IPv6 router on 
           

the Internet.
   

Many ISPs support the anycast address 192.88.99.1, which 
      

           

always means
  

       

"the closest IPv4-to-IPv6 router". When a non-6to4 host 
      

           

wishes to send
  

       

v6 packets to me, it just sends them normally and the 
           

IPv6 Internet
   

backbone will route them to the closest IPv6-to-IPv4 router, 
which will
wrap their package in an IPv4 packet, check the IPv6 
destination address
(2002:52b6:8514:X) and calculate the proper IPv4 destination 
address (my
82.182.133.20 address) from that, and send it to me over 
IPv4. My router
will then unwrap it when it gets it, and forward it over 
           

my internal
   

IPv6 network.
So as you see, 6to4 addresses are something quite 
           

different from the
   

2001::/48 block that you got from your tunnel provider.
 

      

           

The /48 was given to me by the provider.  I am aware of the 
   

        

             

addresses 
 

      

           

construction, just can't figure out how to get the clients 
   

        

             

to connect 
 

      

           

through the router.
   

        

             

I still don't really understand what your actual problem 
      

           

is, after all
  

       

this.
Hope this helps.
Fredrik Tolf
------------------------------------------------------------
      

           

---------
  

       

The IPv6 Users Mailing List
Unsubscribe by sending "unsubscribe users" to [EMAIL PROTECTED]
 

      

           

    

         

---------------------------------------------------------------------
The IPv6 Users Mailing List
Unsubscribe by sending "unsubscribe users" to [EMAIL PROTECTED]

     


 

---------------------------------------------------------------------
The IPv6 Users Mailing List
Unsubscribe by sending "unsubscribe users" to [EMAIL PROTECTED]