IANA Deploying IPv6

According to this Wired news article, IANA has begun to "roll out" IPv6. Though it doesn't go into specifics, one assumes this means that the three major IP registries will begin assigning IPv6 addresses. The article mentions another chicken and the egg problem: no IPv6 software (correct me if I'm wrong, but doesn't Linux have IPv6 software?), so there is no need for IPv6 addresses, and vice-versa. It also mentions every traffic light on the planet could have its own IP. Update: 07/16 02:48 by J : Dave Whitinger at LinuxToday sent a link to a mail which clarifies the situation a bit.

Comments

IPv6

[Anonymous Coward]

IPv6 has 128-bit addressing - enough for every particle in the universe to have its own subnet. This was deliberate. IPv4 isn't really running out of addresses - it's just that IP addresses can't be given out of the whole pot. The address space must be subdivided in order to allow routers to do their job. The IPv6 address space was therefore made large enough that it can be assigned extremely sparsely, without running out of addresses at the subnet level.

There's plenty of IPv6 software to go around, actually - in fact there are many implementations not only of the IPv6 stack, but of protocol layers to allow IPv6 and IPv4 stacks to interoperate. It's just that they're all in beta, and not very many vendors have announced them as products yet. But you can run Linux or *BSD on an IPv6 net today.

In fact, there's a vigorous "6BONE" (like the MBONE) of IPv6-only hosts existing on the current IPv4 Internet via tunneling arrangements. The 6BONE is the proving ground of IPv6 interoperability and routing stuff.

IPv6 assignments

[olmy]

According to the allocation draft document, http://www.arin.net/IPv6.txt, the 3 Registries
won't be initially assigning IP addresses to end users or sites. Instead, they'll be making sub-delegations to TLA registries (a sub-continental registry that will make allocations after the 1st 16 bit boundary of an
ipv6 subnet). So, ARIN, APNIC, and RIPE will begin
issuing TLA's to the TLA registries, who in turn,
will begin making allocations at the NLA level level. These NLA assignments will go to large ISP's. Assignments to individual sites and end-users will be carved out of these NLA assignments.
The last 64 bits is a hard boundary reserved for
the host ID (based on the next-generation EUI-64
MAC address).

Glossary:
TLA: Top-Level Aggregator
NLA: Next-Level Aggregator
SLA: Site-Level Aggregator

Why IPv6

[konstant]

As someone else noted, IPv4 is nowhere near exhausting the supply of IP addresses. The problem is really that the IP#s have been subdivided into hierarchies A-E:

Class A: For big monster domains like ARPAnet
2^7 domains*16 million hosts each
Class B: For medium domains like your ISP
2^14 domains*65536 hosts each
Class C: For subnets and labs and stuff
2^22 domains*255 hosts each
Class D: For subnet-only multicast
Class E: nobody ever really used this

Trouble was that everybody wanted something bigger than C, but didn't really need all the addresses in B. So a lot were wasted every time a B class was assigned. There are some kludgy solutions like masking and sewing together lots of C's into one bigger domain, but they all are horribly complicated and a waste of brainpower as anybody who has ever taken a networking course can attest :) So one problem addressed by IPv6 was the expanded IP# values. Lots of room for divisibility.

A second problem was that IPv4 was basically all about sending text from one spot to another, and there was a lack of optimization for high-prio data and multicast data like streaming video. The reason you'll see a lot of patches for IPv6 stuff is not that it isn't backwards compatible with IPv4 so much as that IPv6 has lots of cool features people will want to take advantage of. For example, you can mark the priority of your packets on a scale of (I think?) 1-5, with servers optionally enforcing these values. When a server was in the process of getting slashdotted for example (or some other DoS attack ;) it would know which packets were important and which could be dropped safely. You'd probably have to pay extra for high-priority transmissions, which means as an added benefit that crackers would have a harder time taking down machines they didn't like by packet flooding them or whatever.

As another example, the IPv6 packet structure basically lets you chain "extensions" onto your packet, giving you a sort of dynamic packet size.

Another biggie is internet-wide multicasting. A group of people receiving the same streaming video wouldn't have to be sent separate copies from the originating server. It could send one and have intermediate routers spawn copies.

A lot of the pain of setting up a new host is also eliminated. There's some kind of dynamic search-and-allocate thing built in that I don't remember well enough to discuss. Something about new hosts asking their neighbors for a globally unique IP address and eventually getting one.

There's more. Get Tanenbaum's book on networking and find out for yourself.

-konstant