Slashdot Mirror
An Introduction to IPv6
Playboy writes "Here is a great introduction to IPv6 in general, the technological background, the reasons for the move and the effects this will have on networks. Understandable for network novices like me but still includes many details on the technological side of things."
Just look at the timestamps (posted one minute after the story was submitted). And the bastard did have a signature referring to karmawhoring, but he's removed it now.
He's passed on (hence the joke, I get it) but in his TCP/IP Illustrated books, he discusses IPv6 thoroughly, including how to write applications to use either protocol seamlessly.
Well, it is estimated that there are ~10^80 particles in the entire universe. Meanwhile there are ~2^128 addresses in IPv6.
So, since 2^128 > 10^80, then yes.
What about the bulbs? How can check to see if they are actually on? How will my switch...
oh forget it... just give me a few million addresses
Get your Unix fortune now!
there will no longer be a need for IP address conservation since there will now be enough IPv6 addresses available for each person on the planet to have 10 of their very own.
Given that there are 128 bits for IPs in IPv6 this translates into 3.4*10^38 IP addresses. I think this comes out to roughly 5.6*10^28 IP addresses per person.
Fly me to the moon Let me sing among those stars Let me see what spring is like On jupiter and mars
The most obvious distinguishing feature of IPv6 is its use of much larger addresses. The size of an address in IPv6 is 128 bits, which is four times larger than an address in IPv4. A 32-bit address space allows for 2^32 or 4,294,967,296 possible addresses. A 128-bit address space allows for 2^128 or 340,282,366,920,938,463,463,374,607,431,768,211,45 6 (3.4 × 1038) possible addresses.
The population of the earth is ~6 billion (US billion). So 56,713,727,820,156,410,577,229,101,238 each
----
No, ::1 is the home/localhost/loopback address. ::0 is when you have no assigned IP address, logically equivalent to 0.0.0.0 in IPv4.
Dozens of /8s are available; last time I checked it was about 40% of the total address space.
Actually some of those issues are covered in IPv6. There is a new address type called an any-cast address. The idea, which will be interesting to see how it's implimented, is that all DNS servers will use an single any-cast address. The routers will somehow be told that this any-cast exists on this particular machine. When someone needs a DNS lookup they will use the hard-code any-cast address for DNS that everyone else in the world uses; however, instead of everyone hitting the same machine, they will hit the "closest" machine with that any-cast address. The same can be true for NTP, etc. Basically these are services that do not require that you have any particular device, just one of any of the ones in the world... preferably the closest or least busy.
No, 6to4 is really that bad - it relies on custom tunnels and special ISP support rather than just specifying it on the routers.
I've played with ipv6 in the past, but after so many years it's still a very long way from useful. Since nobody has ipv6 machines and you need ISP support (which ISPs don't provide) putting up an ipv6 website is a sure-fire way to get zero hits.
It doesn't help that proxies eg. squid don't support it yet.. the project to do it (http://devel.squid-cache.org/ipv6) has been dead since 2001.
Some quick google-based calculations for number of IP addresses for every square inch of the surface of the earth (including the ocean):
:) Hindsight is 20/20.
(2^128) addresses / (7.9*10^17) square inches on earth = 4.3*10^20 addresses/in^2... That's a lot.
But then again, they probably thought it was a lot to begin with
-Jesse
Nothing says "unprofessional job" like wrinkles in your duct tape.
Internet 2 uses it exclusively.
Boy, are you wrong.
WRONG.
(Just that sentence, of course. The rest of your post is right.)
Wrongity-wrong-wrong-wrong.
There are no trails. There are no trees out here.
Recall that they were superseding NCP, which used 8-bit addresses, and were building a network on which multiple hosts attached to a given router. Two bytes might handle that much, but local networks were popping up also. Four bytes seemed plenty, but it was not exactly prescient.
"But all your emitter and collector are belong to me!"
But counting how many addresses per particle or atom or gram is not actually interesting. (Press coverage notwithstanding.) It's what you can do with all that elbow room, like autoconfiguration and perhaps location-independent endpoint identifiers. (Which we almost but not really got.)
"But all your emitter and collector are belong to me!"
Chapter 10. IPv4 and IPv6 Interoperability (starts at page 261)
in Part 3. Advanced Sockets
in UNIX Network Programming
Volume 1
Second Edition
by W. Richard Stevens
ISBN: 0-13-490012-x
Actually 2^128 is ~10^38 so there aren't enough addresses for every particle in the universe but each person on earth could have ~10^28. I think that's enough, for now at least.
Not surprisingly, it's MIT. They own 018.x.x.x
If you have a network with no DHCP server, the computers will fall back to auto-configuration, wind up on the same subnet, and be able to ping each other and have full TCP/IP connectivity between each other, which is enough to do Windows filesharing & other things.
Basically, the old methods had limitations and were complemented by the addition of a third method.
1. Static Configuration (old) -- doesn't require a DHCP server, but takes a lot of work.
2. DHCP (old) -- doesn't require a lot of configuration on the clients, but does require you to have a DHCP server.
3. Auto Configuration (new) -- doesn't require any configuration or a DHCP server, but doesn't let you connect beyond the subnet you're on, and isn't supported by every system.