Mac OS X comes with ipv6 support and it is ready to use. But how to use it? We will find out how in this article.
What is ipv6?

ipv6 stands for ip version 6, opposed to the standard ip protocol in use, which is called ipv4. In ipv4 every address identifying our machines is in the form of x.y.z.t, where every of these fileds is filled with a number going from 0 to 255. These addresses are contained in 32 bits, every field of the address is made of 8 bits. Considering we're talking about numbers represented in base 2, 2^8 = 256 numbers. And that's what we really have: integers from 0 to 255.
ipv6 was created and studied to enlarge the number of internet addresses: the internet growth was so fast that ipv4, from year to year, are becoming too few.

ipv6 addresses are in the form of 8 fields separated by colons. Every field is in hexadecimal format and made of four digits, for a total of 16 bits per field. As an example i give you www6.ppcnerds.org ip:

stitch:~marco$ dig -t AAAA www6.ppcnerds.org
;; ANSWER SECTION:
www6.ppcnerds.org. 1800 IN AAAA 3ffe:bc0:830:1::1


So 3ffe:bc0:830:1::1 is our configured ipv6. What i did was simply asking the dig program to return me the ipv6 (i asked dig for it by passing the -t AAAA parameter) associated with www6.ppcnerds.org.
See those :: colons with no digits in the middle? Well, that means something like "fill with zeros". another way to write the same address would be 3ffe:bc0:830:1:0:0:0:1
As you can see ipv6 hosta addresses don't look that neat and easy to remember, fortunately they're always associated with domain names :)


How can i get my ipv6?

Normally, when you connect to the internet, your ISP provides you with an ipv4 address. At the moment few ISPs in the world are supporting ipv6 native connections. By the way you can still get your ipv6, laying on a "Tunnel Broker". The prerequisite is that your operating system can understand ipv6 protocol. And Mac OS X users have the advantage to run an ipv6-ready OS with an unbelievable easyness for the configuration part.
Our tutorial is based upon the service provided by people at freenet6: it is the easiest to configure, in my opinion, and it works really well (that's my experience with it).

So get to freenet6 homepage and register a free account: i can guarantee that in months of use they did not fill me with tons of mails, i did not receive anything but the password for my account. After you create your account look on their site for the software they distribute to setup the ipv6 tunnel. It is called tspc.

A binary of tspc for Mac OS X-Darwin is already there, but for some reason i found out that no executable is present in the package. You will need to compile the program, it takes less than a minute. Download it and uncompress the .tgz file.

Assuming that the folder with the sources is in your home and is called freenet6, open the Terminal app and type:

cd ~/freenet6

And then type:

make all target=darwin

This will put the tspc binary with a configuration file in the bin directory INSIDE the freenet6 directory.
It is time for some configurations. We must edit the tspc.conf file. Let's use our best-loved taxt-editor to do it. We must add to this conf our username. Look for:

userid=anonymous

and put your registered username in place of anonymous. Do the same thing for the passwd= string, adding your account password.
You are almost ready to go. In this tutorial we are covering the host configuration so just uncomment the host_type=host string by removing the # symbol at its beginning.
Well, we are now ready to go.
Cd to the bin directory typing:

cd bin

An then start tspc:

./tspc -f tspc.conf


Surfing in ipv6

You should be ready to use ipv6. But are your applications ready too?
Many important tools have already implemented ipv6 support. Browsers, irc clients, mail clients and server softwares are all examples of applications that you can usually run in the ipv6 flavour. You can search the net for applications that can understand this new protocol just well.

Am i really using ipv6?

There's an easy way to understand it: point your browser (Mozilla Firebird can handle ipv6 just well on Mac OS X) to [www.kame.net], where the square brackets tell that you are doing an ipv6 request to the web server. Kame home page will tell you if you are using ipv6 or if something went wrong in the setup process and you're still using ipv4.
Mac OS X integrates the work of people at kame.net: the famous "kame stack" used in most of BSD *nixes. Their site is a good starting point to understand all ypu can do with the v6 protocol and how to do it. This tutorial is just to give you an idea of how to use ipv6.

ppcnerds^6 !!

Let's come to us:we are currently offering a number of services in ipv6 too.
A chat server, listening at irc6.ppcnerds.org, port 6667 for clear connections and 6601 for ssl connections.
Our web-server is listening at www6.ppcnerds.org.
And our mailboxes can be checked via ipv6 connecting to posta6.ppcnerds.org, pop3, imap, pop3-ssl, imap-ssl.
And it is all free, of course. If you want to request a mailbox just frop a mail to ppcnerds@lists.ppcnerds.org. If you want to talk with us just join #ppcnerds on our irc server. And if you do it using ipv6 we will understand that maybe this tutorial was useful to someone.