IPv6

In the wee hours of 26 March 2000, ipv6.bits-pilani.ac.in

became the first network from India to be on the 6Bone.



IPv6@BITS aims at building IPv6-related technologies, and educating and
providing support to other organizations–mainly in India–with similar

interests.

What, Why, and When: The 3Ws of IPv6



The Internet has grown at a phenomenal pace in the last few

years. It no longer serves just the intelligentsia, but has become a medium as

common as television or radio. According to a recent estimate, there are about

195 million users on the Internet today, as compared to 49.2 million in 1995.

Also, the impending convergence of the computer, communications, and

entertainment industries dictated that the Internet Protocol (IP) had to evolve.

IPv6 was conceived to remedy the problems faced by IPv4. The

present IP (IPv4) address space–for example, 192.168.1.211–uses a maximum of

12 digits that needs 32 bits in binary. Hence, a maximum of 232 (4,29,49,67,296)

unique addresses can be allotted to computers on the Internet. The current

explosion in the number of machines on the Net means that we’d run out of IP

addresses in a few years from now–and that would mean stagnation or death of

the Internet.

Foreseeing these problems, scientists started working to

develop the Next Generation Internet Protocol (IPng), which matured into what we

know as IPv6 (Internet Protocol version 6). IPv6 uses a big (128-bit) address

space, and offers other better features over IPv4.

How BIG is big?



The maximum number of unique computers in the IPv6 Internet

is 2128, which is equal to 340,282,366,920,938,463, 463,374,607,431,768,211,456.

You could reject IPv6 with the notion that 2128 can also be

consumed in the decades to come. But before that, you need to comprehend the

massiveness of this number. In a theoretical sense, this is approximately

665,570,793,348,866,943,898,599 addresses per square meter of the surface of

planet Earth. As a small exaggeration, IPv6 can provide addresses to every

molecule on earth. This means that even if the explosion of the network is many,

many times worse than what it is today, we’d still be left with billions and

billions of unused addresses for decades to come.

Organizations worldwide are competing in the race to develop IPv6-capable

applications that use its special features

like security, multicasting, flow-labeling etc. You can also

be a part of this development effort by joining hands with other project teams

or by starting a team yourself.

Setting up an IPv6 router



6Bone is the network of all IPv6-capable routers. To connect

to 6Bone, you need at least the following–an IPv6 capable router or a host

capable of routing; a globally routable IPv4 address; a 6Bone access point,

which is willing to support you; and finally, lots of patience.

Setting up a IPv6-capable machine



The latest versions of most OSs come with IPv6

implementations. So, you can skip this in case your OS is out-of-the-box IPv6

capable. If you don’t understand what we’re talking about here, kindly

continue reading this part.

Before attempting to connect to the 6Bone, you should have

set up your system to support IPv6. The router can either be a hardware router,

or a host which is configured to act as a router.

Some common implementations are:

Linux



Linux kernel 2.2.10 onwards supports IPv6. But you still have

to download IPv6-capable applications. Some of them have been distributed in

this month’s CD under GNU General Public License and are also mirrored at http://ipv6.bits-pilani.ac.in/. 

Red Hat Linux 6.2 supports IPv6 out-of-the-box. That is, all

network applications support IPv6 directly. Read the HOW-TOs and install from

CD.

Win NT 4 +



Go to http://research.microsoft.com/msripv6/

for more

information. Win 2000 is out-of-the-box IPv6-capable.

FreeBSD 4



This is also IPv6 capable. So, all you need is a download

from http://www.freebsd.org/. 

Other OSs



Go to http://playground.sun.com/ipng/ipng-implementations.html

to check for implementations under other operating systems.

Testing for IPv6 compliance

Testing for IPv6 compliance



Try pinging yourself–ping ::1 (localhost). After starting

other IPv6 services, try talking to them, either as localhost or through other

IPv6 machines on your Ethernet connected directly. Machines should be connected

through UTP hubs/BNC only, that is, without any router or IP-selective device in

between.

Choosing your 6Bone access provider



Once you’ve set up a host with IPv6, the next step is to

find a 6Bone access point closest to you. The easiest way is to go to

www.6bone.net, get the list of 6Bone access points in your country, and find one

that is the least number of hops from you. Once you’ve found a site, check the

Whois listing to find out the contact person for the site at

http://whois.6bone.net.

Setting up the tunnel



After the site agrees to host you, you have to set up a

tunnel endpoint. You’ll need the following information for that.

• IPv4 server address: This is the IPv4 address of the
  
  host site.

• IPv6 server address: This will be the next hop for all
  
  your IPv6 packets.

• Your IPv4 address, which you’ll have to provide to
  
  your host site.

• An address prefix: This is the network portion of your
  
  site. Depending on the size of your prefix, you can subnet it internally.

How does tunneling work at the network level?



Say, acme.edu wants to connect to 6Bone. They find that

ipv6.nowhere.org is the nearest 6Bone point from the Whois list. So, they

contact ipv6.nowhere.org and ipv6.nowhere.org agrees to support them.

acme.edu IPv4 address: 202.54.26.111

ipv6.nowhere.org IPv4 address: 140.125.1.1

ipv6.nowhere.org IPv6 address: 3ffe:327f::/32

They set up two tunnel endpoints, one at acme.edu and another

at provider.org. ipv6.nowhere.org also allocates 3ffe:327f:0b00::/48 as the

network prefix for acme.edu. Usually most 6Bone providers keep a separate

address space for allocating tunnels. Let 3ffe:cfff:a111:b111::321 be the IPv6

address at the ipv6.nowhere.org end and 3ffe:cfff:a111:b111::322 the IPv6

address at the acme.edu end.

Routing at the server end



IPv6.nowhere.org will have a routing table entry with

3ffe:cfff:a111:b111::322 as the next hop for any packet with network prefix

3ffe:327f:0b00::/48. 3ffe:cfff:a111:b111::322 is accessible through

202.54.26.111.

Routing at the host end



If ipv6.nowhere.org is the only tunnel from acme.edu to

6Bone, every IPv6 packet except ones with prefix 3ffe:327f:b00::/48 should be

next hopped to 3ffe:cfff:a111:b111::321.

3ffe:cfff:a111:b111::321 is accessible through 140.125.1.1

3ffe:327f:b00::/48 packets will be routed locally according

to how acme.edu allocated its address space.

RIPE Whois database entries



The database is mainly divided into two parts, one for

networks and the other for the people behind them. The network database is used

for routing policies and other useful data for Internet Network Management,

whereas the people database is mainly for contact purposes. You can make an

entry in the database by sending an e-mail to autodbm@whois.6bone.net. An

acknowledgment is sent back by autodbm in case of success. Otherwise, an error

message is sent back with proper reasons.

The correct format for the entries are available at

www.6bone.net for quick reference. www.kessens.com/~kessens/6bone/ contains

detailed information on the same. This is a must-study for anyone venturing into

IPv6.

Note that the entry should be in exactly the same format as

in the HOW-TO. Some mail clients try to indent the message. This would result in

improper submission.

C H Balaji ,



Deepak Kameshwaran G ,



and T V Raghavan