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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."
Introduction to IPv6 #1004040... This has been brought up every six months or so for quite some time and I usually post the same shit about how it's not practical at this time period for much other than reverse DNS on IRC. But this "article" is yet another worthless explanation of the same old shit.
Take for example the following IPv6 address: 43FB:0000:0000:0000:0000:BB3F:A0A0:0000 This could be shortened to 43FB::BB3F:A0A0:0 instead. Now you might ask: "What's up with the double colon?" If you thought that, good for you. You've seen something many people would not have seen on their first try. The double colon (aka "::") signifies that we have removed a series of hexadecimal blocks from the address. These will always be contiguous zeros. AKA "0000:0000:0000:0000" can be shortened to just "::". Therefore when you see the double colon in an IPv6 address, it can be automatically assumed that they are all zeros.
Ahh yes, "simplifying IPv6 addresses". No, there is nothing simple about remembering those addresses (haven't there been studies that say 7-10 numbers in a row is about all we can remember?) So here we have 10+ numbers and letters that don't make much sense (yeah some people have gotten vanity IPv6 addresses like ABCD::BEEF::). Nothing is simplified there until you get the DNS up and running for it (not that this is hard or anything but it isn't exactly easy)
It is true that IPv6 is not human friendly; however, in the long run, it will help solve a lot of issues with the current shortage of available IPv4 addresses on the internet.
Yeah, the "shortages"... Just tell the people hoarding all the damn addresses to hand them over. Sorry but MIT, Apple, etc, as much as I respect their contributions to the human race, do not need a Class A. Allow for the redistribution of the IPs and we should be good to go for quite some time.
Be thankful people don't have unlimited IPs in their house. Most people that want to have multiple computers connected to the Internet use a NAT router and at least protect themselves SOMEWHAT from the outside threats. Can you imagine what would happen if all the Comcast retards were straight to the Net with their own IP on each computer?
ISPs make some good money (hell mine gets $5/mo more out of me for an additional IP) selling off static/dynamic IP space. You think Comcast is going to move for a switch when they make $10/mo per extra IP?
I'll just wait for W. Richard Steven's book on IPV6. That'll explain everything.
Best Buy can have you arrested
It's not a bad introduction, but since this is slashdot, I've got a couple of things that I want to point out:
/48s, giving the customer 16 bits of addressing power. However, customers of Tier 2 ISPs will only get a couple SLAs or so. If I am a small business with one of the SLAs, there is still the problem of BGP multihoming with this address space, and this absolutely needs to be resolved in the not-so-distant future. I don't think there's a facility where I can go to ARIN and request my own /48 to annouce, say, between Level 3, MCI, and AT&T. While this might not make a difference to most people, it is a problem on the transport side of the house.
The article suggests that DHCP will no longer be necessary. This is not necessarily true. IPv6 autoconfiguration will get you an address to get onto the net at large, but it will not give you your DNS servers, time servers, or any number of goodies that DHCP is capable of serving up. Autoconfiguration does remove the neeed to define all kinds of crazy scopes, but it doesn't help with other configurable options.
There is exists a problem with multihoming small entities that need provider diversity in IPv6. Some companies are assigning each customer their own NLA, or
// Agent Green (Ian / IU7 / KB1JQO)
// IEEE 802.3: All 10base Are Belong To Us
I didn't understand why we needed IP6 until one of the guys at work described why he wanted each of his light switches to have its own IP address...
...that's why we need IP6.
Idiots...
(just kidding, boss)
AC
Was it poor planning? The article states that there was an unexpected explosive expansion of the Internet. I believe it's like the Y2K problem, they didn't think their programs would still be in use around 2000, so they only needed to store a two digit year. The same happened here, they didn't realize the Internet would become the World Wide Web, the New Economy, etc. Hell, even Bill Gates didn't see it coming.
There's no place like 0:0:0:0:0:0:0:1
Is that a typo in the department line or is it intentional?
Either way it's hilarious.
I for one, welcome our new 128 bit overlords!
You seem to understand the technical issues very well... Sorry, but since this is
Please, oh please, let that be a joke...
If this is a measure of when people will start using IPv6, the answer is today. It's already there. Every major TCP/IP stack out there supports IPv6. Tunnel networks exist through IPv4. Internet 2 uses it exclusively.
When are corporations going to start moving to IPv6? Who knows...that will depend on individual needs, but in general, large corporations aren't going to see a big need to move towards IPv6 any time soon. Without end user by in, who is going to 'force' people to use IPv6?
Yes, IPv4 space is running out. It has been for a long time. That's why Network Address Translation and private address space are so common in today's world. They may be hacks, but they do the trick. Where's the business case involved in reorganizing major networks?
My UID is the product of 2 primes.
The article instantly delcares that IPv4 was short sighted because it didn't allow for enough IP address but is IPv6 any better? The articles states that it will allow every person in the world to have close to 10 IPs but with the expanding products that carry addresses could this be short sighted as well? Think about the products that people are getting or are supposed to have within the next 20 years.
Phone (Voip)
Cell
Computer (could be many)
TV (could potentially need IP)
Webcams
then we have the possible use that people keep proclaiming will happen
Fridges, and other appliances. This list could continue to grow and I could potentially see 100 being the closer value for many folks in many years. This being said of course not every person in the world is going to need lost of IP addy's since many people dont even need to use one now.
But just think how fast the growth of Ip-Address need has grown in the past 30 years and use that to predict the growth for the next 30. As soon as there are available addresses people will use them. The only reason they aren't being used as liberally now is because they are not available.
We might look back in 10 years and think how short sighted IPv6 was and why another 2 byes weren't just added to the protocol to make its growth laster for many, many,.... years.
Note to web page designers:
Dark characters, light background, sans serif fonts. Trust me. People way smarter than you and mr have already figured this out.
"I'd rather be a lightning rod than a seismometer." -Ken Kesey
Oh, and I almost skipped the obligatory bashing - his first reference at the bottom of the article is Understanding IPv6 by Microsoft Press.
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
I don't think so. Even if he discounts the bits in the addressing architecture responsible for routing and local/global flags and just focuses on the global unicast address space, that still gives you 64 bits (see Section 2.5.4 of RFC3513).
(2^64)/10000000000 = 1844674407.37 (approximately)
And that's assuming ten billion total world population. It's not just ten addresses; everyone can network his/her own cold-fusion-powered TOASTER to the Internet and we wouldn't run out of IP's anytime soon.
Come on guys, theres this thing called IPV8.
get with the program!
augh!
Now if we can just find out what happend to Netscape v5.
Last time I looked at IPv6, it seemed there was no way to multi-home hosts to two or more ISPs. Of course, this capability is essential for IPv6 to succeed. BGP has scaled pretty well thus far, but it is impossible to support peering on IPv6 like it is done on today's internet due to the size of routing tables and it's heirarchical nature. Anyone familiar with this problem or know if any progress has been made?
Don't need to move entirely- just get a NAT that supports IPv4 on the LAN side and IPv6 on the WAN side. No problem.
SJW: a person who perceives an injustice, and while correcting it, commits a greater injustice.
I was under the impression that a 128 bit addressing scheme was enough to directly address every molecule in the Universe with some bits left over. Why then is IPv6 limited to 60 thousand million addresses? I understand that some addresses cannot be used because of multicast addresses and some other things like that, but what other sort of limits reduces the available range down to such a (relatively) small number?
Can you reserve addresses yet?
;-)
I want dead:beef:dead:beef:dead:beef:dead:beef
I had it all caps but the lame-ass lameness filter yelled at me
I thought it amazing that the designers of IP carved out a 32-bit address rather than 16. When there was just a couple of universities on the internet, who woulda though 4 billion addresses would eventually be needed? But our author says with IP v6, we get enough addresses for every person on the planet to have 10 of their own. Let's see... 5 billion people, 10 addresses each... 50 billion? IP v6 only offers up 10 times the address space? I don't think so!
- The Kessel run is for nerf herders. I can circumnavigate the entire Central Finite Curve in a lot less than 12 parse
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.
For Fedora Core users stuck without a direct IPv6 connection (read: most of the world), I wrote a quick IPv6 6to4 setup guide.
6to4 is "automatical tunnelling", which in layman's terms means you don't have to bother your ISP or a tunnel broker in order to set up IPv6 on your network. Most OS's these days (not only Linux but *BSD and Windows) fully support basic IPv6, including 6to4.
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.
What? There is nothing in IPv6 about this. You can do this right now, today, with IPv4 by having a flexible queueing methodology and flexible packet pattern matching systems. Violla. Any packet destined to network 1.2.0.0/16 that is TCP and port 80 no gets dumped in the high priority queue.
QoS is also the perfect snake oil. In a practical sense, QoS only "kicks in" when there's contention, when there's more data that needs to squeeze in to the pipe than can fit. QoS makes the choice of which packet gets to go over all the other packets waiting to go.
In other words, the only time QoS is of any good is when you are on a over subscribed, saturated network, where there isn't enough bandwidth available to meet demand. In simple terms, the network is broken, and QoS just helps pick who gets screwed the least.
Lastly, routing will be simplified because the IPv6 information header on each packet is far more flexible and can contain more detailed information than an IPv4 header thus allowing for faster routing of data across a network or the internet. Currently, most routers need to maintain as many as 48,000 different routes in their routing tables just to effectively route data that passes through them. IPv6 reduces this number by at least 75%.
This, too, is just flat out wrong. The only way this works is if you have a "clean slate" and parcel out IP addresses in a country/provider hierarchal fashion. Want to move providers? You get new IP's, out of their block. Want to multi home? Well, that kinda blows the efficiency right out of the water because now your network is no longer contained within the providers supernet, you have to announce your individual network both via your provider and where ever else you're peered. Therefore, you just added networks to the global routing tables.
Now, quick show of hands... how many of you want to run your systems off a single homed, single provider only network? And please, none of this god awful "let the router pick which source IP to use!" crap.
Also, if you're worried about IPv6 requiring you to change all of your software, learn new protocols, new methods of connecting, new ways of sending and receiving data or anything like that, fear not. The only thing really changing with IPv6 over what was in IPv4 is that you now have a larger address space which allows for more network addressable IP addresses, a more flexible header and packet system, and faster routing.
Yea, you don't have to change a thing. Not any of your software, or nothin'. Of course, you do need a whole new IP stack to talk IPv6, but that's pretty minor right? Windows folks can make this change by simply cracking open their registries and changing the IP Version key from 4 to 6. Ta da!
Faster routing? How's that? Does it make sense to anyone that looking up a 128 bit address is going to be faster than looking up a 32 bit address? There's more to look up.
Furthermore, all routers worth their salt use hardware accelerated forwarding engines these days. Modern BiCAM's or (nearly always) TCAM's can do single cycle lookup of an address out of a potential 512K entries. It doesn't matter how many entries there are, it can always do find the correct match in a single cycle. And 512K entries is a bit more than a default free routing table (~140K entries) that's common today, so there's no worries there.
The catch is, most of these hardware lookup engines are hard wired for IPv4, and can't easily be extended to IPv6, which means the packets become exception packets and need to be dealt with by the CPU. The CPU lookups are orders of magnitude slower than the hardware lookups. This means that performance for IPv6 goes right through the floor for most routers. Newer routers/blades are starting to come with IPv6 hardware accelerated, but there's an awful lot of infrastructure out there that has no IPv6 hardware acceleration.
Therefore, for most people, IPv6 will initially result in a signfigicant performance drop in terms of packets per second over IPv4.
Contary to popular belief there is very little added security
Really? They block incoming connections to a computer, which is a great security enhancement. A NAT box will prevent you from accidentally sharing your hard drive with the world, unless you explicitly allow it. An unpatched Windows machine lasts 16 minutes or so before being compromised - unless it is behind a NAT box. You will also be protected from all worms that depend on incoming connections to propagate, as well as Messenger spam.
So - please explain to me what is so insecure about NAT.
MAC addresses aren't guaranteed to be unique, and they're useless for routing. You can look at the IP address on a packet - whether IPv4 or v6 - and quickly tell where it should go next. You can't do the same with MAC addresses, though: routers would have to keep a table of every single MAC address on the Net (!!) to route packets properly.
TANSTAAFI: There Ain't No Such Thing As A Free iPod.