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The IPv4 Internet Hiccups

Soulskill posted about 3 months ago | from the if-it-ain't-broke,-don't-negligently-let-it-break dept.

Networking 248

New submitter pla writes: Due to a new set of routes published yesterday, the internet has effectively undergone a schism. All routers with a TCAM allocation of 512k (or less), in particular Cisco Catalyst 6500 and 7600's, have started randomly forgetting portions of the internet. 'Cisco also warned its customers in May that this BGP problem was coming and that, in particular, a number of routers and networking products would be affected. There are workarounds, and, of course the equipment could have been replaced. But, in all too many cases this was not done. ... Unfortunately, we can expect more hiccups on the Internet as ISPs continue to deal with the BGP problem." Is it time to switch to all IPv6 yet?

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hmmmmm (2, Funny)

Anonymous Coward | about 3 months ago | (#47661951)

Surely 512k ought to be enough for any router?

Re:hmmmmm (0)

Anonymous Coward | about 3 months ago | (#47662071)

Goddammit! It's 640k you insensitive clod.

Betteridge (-1, Redundant)

Anonymous Coward | about 3 months ago | (#47661953)

"Is it time to switch to all IPv6 yet?"

No.

Re:Betteridge (3, Insightful)

NotDrWho (3543773) | about 3 months ago | (#47662045)

You're right. It was time 10 years ago. Now it's way PAST time.

Re:Betteridge (3, Informative)

BitZtream (692029) | about 3 months ago | (#47662163)

Except that this has nothing to do with IPv6. IPv6 will do nothing to resolve this problem and will in fact make it worse because the problem itself is due to a router not having enough RAM and nothing about IPv6 results in less RAM usage.

Sure, we should get on the IPv6 bandwagon, well, except it sucks right now and can lead to some annoying connectivity issues when sites are misconfigured, or setup IPv6 and then forget about it so you're trying to connect to an IPv6 address thats no longer used because no one bothered to update DNS ... or their IPv6 connection is through one of their shitty over saturated links.

My ISP does IPv6, as does all my equipment. I had to disable it so that the rest of my family doesn't wonder why random sites don't work on their PC but work fine on their phone and while I can't remember the ones off to the top of my head, there are some big ones that regularly fuck up. Hell, even Google's IPv6 connectivity is shoddy at times.

Re:Betteridge (5, Informative)

Anonymous Coward | about 3 months ago | (#47662231)

One of the design goals of IPv6 was to reduce the size of the global routing table. That's why there are so many more addresses in IPv6 than there are ever going to be devices. Each provider gets so much address space that nobody needs to come back for more. That means there's no address space fragmentation due to address scarcity, like there is with IPv4, where providers usually have dozens or hundreds of separate allocations which can't be aggregated and must all be entered into the global routing table. IPv6 addresses are four times as long as IPv4 addresses, but there are far more than four times as many routing table entries per ASN with IPv4 than with IPv6

Re:Betteridge (4, Informative)

devman (1163205) | about 3 months ago | (#47662401)

Also routing only occurs on the first 64-bits of an IPv6 address, the router doesn't need to store the host last 64-bits of an IPv6 address.

Re:Betteridge (4, Informative)

Bengie (1121981) | about 3 months ago | (#47662443)

Core routers only use the first 48bits as that's the smallest block that is routable on the Internet. Which is why IPv4's /24 vs IPv6's /48 explains the routers supporting 1024K IPv4 routes or 512K IPv6 routes or a 512K/256K split. Exactly 2x difference. But IPv6 has sparse allocations resulting in about an effective 10x reduction in the number of routes.

Re:Betteridge (1, Insightful)

BitZtream (692029) | about 3 months ago | (#47662463)

That doesn't solve the problem, it mitigates ONE aspect of the problem.

It will effect large ISPs with large numbers of IPs, which are few and far between.

It does nothing to resolve the actual problem of router table growth which is caused by the number of networks, multihoming and address portability.

Multihoming and address portability make what you've said irrelevant, and thats where the growth comes from.

Re:Betteridge (1)

Anonymous Coward | about 3 months ago | (#47662651)

You can talk all you want about what should and shouldn't be irrelevant, but at the end of the day the IPv6 routing tables take up less space in memory. Maybe you haven't noticed because you're too busy disabling things,blaming configuration problems on the underlying protocol.

Re:Betteridge (2)

slashmydots (2189826) | about 3 months ago | (#47662905)

It's TCAM, not RAM, which is A LOT faster than RAM. That's why it's a problem that it's over 512k. Most routers have more than 0.5MB of RAM.

Re:Betteridge (5, Funny)

DickBreath (207180) | about 3 months ago | (#47662601)

The Mayans had predicted that we would run out of IPv4 addresses in 2012 -- and they were right.

Re:Betteridge (1)

The New Guy 2.0 (3497907) | about 3 months ago | (#47662973)

Was there a 10 year warranty on that? Seems like to fail all at once now is a sign of something intentionally wrong.

Re:Betteridge (0)

Anonymous Coward | about 3 months ago | (#47662057)

DAMMIT

OK, let me try that again:

Is it time to... stick with IPv4 instead of switching us all to IPv6?

Re:Betteridge (1)

Anonymous Coward | about 3 months ago | (#47662249)

It's Betteridge's Law of Headlines and it doesn't apply: The question isn't in the headline.

Yes, Please (4, Interesting)

jfdavis668 (1414919) | about 3 months ago | (#47661967)

We changed all our systems over time to handle this great IPv6 change, and haven't used IPv6 yet. Our service provider doesn't even offer it. Come on, some of us are more than ready. We will probably have failures, because it hasn't been truly tested, but we are far more ready than we were for Y2K.

Re:Yes, Please (3, Funny)

CastrTroy (595695) | about 3 months ago | (#47662011)

And home users aren't even close to getting on board. Most people's PCs and other devices will handle IPV6 just fine. Many new home routers are ready but a lot of people haven't bought a router in years, and their old one can't handle IPV6. And at least where I am, there aren't any home ISPs who even have IPV6 on the roadmap.

Re:Yes, Please (4, Insightful)

NotDrWho (3543773) | about 3 months ago | (#47662125)

Many new home routers are ready but a lot of people haven't bought a router in years

So? Most people hadn't bought a broadband router at all 15 years ago. Most people hadn't bought a wireless router 10 years ago. People don't buy until you give them an incentive. And until you man up and tell people "Look, you have a year to buy an IPv6 router or get one from your ISP, or we're cutting you off" no one has any incentive to get off their fat asses and do what needs to be done to move us ahead.

If we had continued to keep the automobile speed limit at 10 mph year-after-year because a few lazy old farts refused to give up their goddamned horses and buggies, we'd still be driving around today at 10 mph.

Re:Yes, Please (2)

Bing Tsher E (943915) | about 3 months ago | (#47662187)

Most people don't need to drive more than 10 mph in their driveway. And most people don't need router technology in their home that's newer than 10 years old.

It's the dilemma of the marketers. Cisco says 'buy new stuff.' News at seven.

Re:Yes, Please (3)

arth1 (260657) | about 3 months ago | (#47662885)

And most people don't need router technology in their home that's newer than 10 years old.

Once their OS is told that www.google.com has internet address 2607:f8b0:4009:805::1010, they sure do.
Or once their ISP switches to IPv6.

What's sad is that slashdot.org does not have an AAAA address.
News for whom?
Stuff that what?

Re:Yes, Please (1, Informative)

BitZtream (692029) | about 3 months ago | (#47662189)

If we had continued to keep the automobile speed limit at 10 mph year-after-year because a few lazy old farts refused to give up their goddamned horses and buggies, we'd still be driving around today at 10 mph.

19 mph, because no one pulls you over for doing 9 over, but 10? You're in the pen!

Re:Yes, Please (2)

BitZtream (692029) | about 3 months ago | (#47662181)

WiFi routers get replaced fairly regularly because the cheap ones most people buy have some crappy component in them that starts to degrade over time until their wifi becomes really crappy to use.

Unless you pay a lot for quality gear, or you get lucky, 5 years is a long time for a consumer/home user WAP to last. If you see a Dlink or Linksys WAP thats 5 years old and still works well, you're indeed lucky.

Not from what I've seen (3, Insightful)

Sycraft-fu (314770) | about 3 months ago | (#47663039)

Not the fact that wifi routers degrade, you are totally right about that, but that people will replace them. I'm amazed at how shitty someone's Internet can be and they have an "Oh well, whatever," attitude about it.

A good example near and dear to me is my parents. They moved in to their current place about 7 years ago and got a cheapass Linksys router to handle their NAT and WiFi. It has been giving them enough grief for me to hear about it for at least 3 years. They are not poor, a new router is not a big deal, yet they didn't get one. So I got tired of it, and also had an easy solution: When they were visiting me this June I upgraded my WAP to a new 802.11ac one and gave them my old one, which was working great.

They still haven't installed it. It's not like they don't have time, mom is retired and dad is semi-retired, it's not like it is hard, it is much simpler to set up than their old model and they can always call me. They just haven't bothered. Their router acts up, they go reset it, and don't bother to replace it.

Another somewhat related example would be a friend of mine. He's a young guy, under 30, and quite technically savvy. He's complained to me that the Internet at his house is not meeting advertised speeds, going quite well below it. Strange, since we are both on the same ISP, and live only a couple miles from each other and my experience has been that they always are right around max. I inquire a bit more and find out he still has a DOCSIS 2 modem. Ahh ok, well that is probably the issue. Though his connection is of a speed that a single DOCSIS channel can handle (25mbps), that modem has one one channel to choose from and it could well be too loaded down by other people on the segment. So my recommendation was to get a DOCSIS 3 modem. An 8x4 modem that is compatible can be had for like $80. That should solve any speed issues since now there's a bunch of channels to choose from, and will be compatible when they bump the speeds in the future.

He didn't want to spend the money, and so just complains occasionally about the speed.

For whatever reason, there are more than a few people who will just use old, failing, technology and bitch about it rather than fix the issue.

Re:Yes, Please (1)

Anonymous Coward | about 3 months ago | (#47662239)

I have native IPv6 at home since several years. I just had to toggle a button on my ISP (Free in France) account page.
Last time I used a packet sniffer (for unrelated geeky reason) a part of traffic actually was IPv6.

Re:Yes, Please (1)

Russ1642 (1087959) | about 3 months ago | (#47662279)

Home routers fail after a few years anyway so most home users are probably IPV6 ready.

Re: Yes, Please (1)

jd2112 (1535857) | about 3 months ago | (#47662393)

Home users are on IPv6 because it has been enabled by default since at least Windows Vista. That doesn't mean that their internet connection can handle it as the providers are more interested in finding new ways of throttling traffic and extorting money out of service providers to bother with making improvements to their networks that most customers won't notice and haven't asked for.

Re:Yes, Please (1)

Dishevel (1105119) | about 3 months ago | (#47662907)

My home router is a computer that can not run the apps I want anymore and a few nice network cards.

Re:Yes, Please (2)

dbIII (701233) | about 3 months ago | (#47662295)

Many new home routers are ready but a lot of people haven't bought a router in years

When they or their kids discover bittorrent or Facebook jumps the shark in the number of connections per page even more than it has they'll find that the net just will not behave as nicely for them anymore with their old router that wasn't designed to be hit that hard. When they get their new cheap and nasty bottom of the range Chinese device they'll find it can both vastly outperform their old thing and later it will handle IPv6 for them.

And at least where I am, there aren't any home ISPs who even have IPV6 on the roadmap.

The US still has a few addresses floating about but Asia had a smaller pool to play with so the people that make your stuff are already using it on IPv6. Even in the US phones are getting on IPv6 so since everyone wants their site to actually work on an iPhone the content hassles are being worked out before the US home consumers arrive.

Re:Yes, Please (1)

Lord Crc (151920) | about 3 months ago | (#47662527)

My ISP supports IPv6, my router supposedly supports IPv6 (Asus RT-N66U), I can see the router getting an IPv6 address from my ISP, I can see my PC getting an IPv6 address from my router yet when I test it out on the various "do I have IPv6" pages it's failing.

After spending a couple of hours mucking around I gave up. I'll deal with it when it matters. Hopefully it's less painful then.

Re:Yes, Please (1)

Scutter (18425) | about 3 months ago | (#47662631)

That's been my exact experience. IPv6 is supposed to be dead simple (compared to IPv4) for home users. I am definitely not a home user and I still can't get it working with my ISP.

There are new routers that don't work (4, Informative)

Chibi Merrow (226057) | about 3 months ago | (#47663005)

I actually bought a new router within the last year. A "nice" Buffalo model with DD-WRT built in. Only to find out DD-WRT doesn't support native IPv6 (which my old, faulty NetGear did, go figure). They just support Toredo or other tunneled IPv6 solutions.

Man, was I disappointed.

Re:Yes, Please (0)

Anonymous Coward | about 3 months ago | (#47662191)

This has little to do with IPv6. In fact there is only 256k available by default if you switch. I suggest the BOFH change the default password on their router while they are changing the default TCAM.
The way I figure it, we have a good chance of bypassing IPv6 alltogether if we put a little more work into RDAM and stuff all networking into private application layers. Nobody wants to visit your blog anyway.
I call it my Software as a Sucker model.

Lack of incentives...? (1)

beh (4759) | about 3 months ago | (#47662283)

To some degree obviously, there is a lack of incentives for ISPs to change - if they still have enough addresses for themselves, then switching to IPv6 is only costs, not benefits.

Maybe some of the larger sites, like youtube, facebook, wikipedia should have a meeting to discuss the switch-over and then start shaping IPv4 traffic - just reduce capacity on IPv4 by 5% every month and see how long it will be, before ISPs will lose customers if they DON'T switch to IPv6...

Re:Lack of incentives...? (1)

macromorgan (2020426) | about 3 months ago | (#47662667)

ISPs have no competition, but Youtube, Facebook and Wikipedia do. The only thing those sites would do is shoot themselves in the foot while trying to force an immovable object to bend to their will. Lobbying the FCC on the other hand, that could actually affect change. It would be in the best interest of everyone (excluding short term investors in the various ISPs), with networking equipment manufacturers poised to win the biggest. I think it's all moot though, as Comcast is reportedly very far into their IPv6 rollout, as is Time Warner Cable (I have full dual stack at home with my TWC service). AT&T reportedly has rolled theirs out too, but some customers have experienced issues as the MTU setting is different on IPv6 as it is for IPv4. I also know first hand that Verizon Wireless runs dual stack over their LTE network. At this point, I think it's really just getting the proper equipment in the hands of customers that is the hindrance.

Re:Lack of incentives...? (0)

Anonymous Coward | about 3 months ago | (#47662779)

Wikipedia has competition? From whom?

Re: Lack of incentives...? (0)

Anonymous Coward | about 3 months ago | (#47662861)

I think Facebook and YouTube have enough clout.

Re:Lack of incentives...? (1)

Dishevel (1105119) | about 3 months ago | (#47662949)

Lobbying the FCC on the other hand, that could actually affect change. It would be in the best interest of everyone (excluding short term investors in the various ISPs), with networking equipment manufacturers poised to win the biggest

You know I was just talking with the wife last night about how of all the government agencies the FCC has always listened to the people and done the right thing,

The only truth there is the really surprising one. A /.er with a wife.

Re:Lack of incentives...? (1)

arth1 (260657) | about 3 months ago | (#47663033)

The only truth there is the really surprising one. A /.er with a wife.

Wives are like PCs. If you need one, you need several. And you can always hack someone else's to use.

Are the sites you want to visit ready? (1)

Marrow (195242) | about 3 months ago | (#47662757)

If they can't hear/speak IPv6, then the Internet is going to feel like a very big empty room. Everyone needs to change to the new protocol. Everywhere. And IPv4 still has to work. Everywhere.

IPv6 (-1)

Anonymous Coward | about 3 months ago | (#47661975)

Seems useless and not future proof.
I call for IPv128.

Is it time to switch to all IPv6 yet? (1)

Anonymous Coward | about 3 months ago | (#47661989)

Well, if you pay for the cost, otherwise it will be much easier to just patch the problems and keep on going.
That way we will have access to more mature technology when we do make the switch. Also, it is unfeasible to switch it all at once.
Gradual switching when needed is preferable.

Re:Is it time to switch to all IPv6 yet? (4, Informative)

marka63 (1237718) | about 3 months ago | (#47662029)

How much more gradual do you want? I've been running dual stack for over a decade with a tunnel back to HE. At this stage most of your equipment runs fine with IPv6.

Re:Is it time to switch to all IPv6 yet? (3, Funny)

Bengie (1121981) | about 3 months ago | (#47662033)

In many cases, the "work around" is to use software routing instead of hardware routing. In the cases of the Cisco routers linked above, their TCAM can be re-partitioned, then restarted. But with the rate of IPv4 route fragmentation, it will only buy so much time. The fix is to use IPv6 or get newer hardware with a larger TCAM.

Re:Is it time to switch to all IPv6 yet? (1)

NotDrWho (3543773) | about 3 months ago | (#47662171)

Well, if you pay for the cost, otherwise it will be much easier to just patch the problems and keep on going.

Yeah, in the same sense that it's easier for a Calcutta slum to keep running recycled appliance cording as power lines rather than adopt modern electrical standards. At a certain point, putting another shitty patch on an ad-hoc fucking mess has to give way to some kind of organized system, even if it means some short-term pain. We can't have piss and shit running down the street because some of the neighbors don't want to put up with the hassle and cost of building a modern sewer system.

Re:Is it time to switch to all IPv6 yet? (2)

Bing Tsher E (943915) | about 3 months ago | (#47662209)

Everything is a patch. Everything is an update. There's no such thing as 'rip everything out and reinstall.'

Well, there is, but it failed the several times it was tried in the 20th century.

Get used to the maintenance cycles. It's really all we've got.

Not ready for v6 yet (1)

oodaloop (1229816) | about 3 months ago | (#47661993)

There's still plenty of time to postpone that. Not until the last /2 is sold will I start to worry. And can't we start using a few 127.x.x.x? Do we really need 16 million addresses for testing?

/sarcasm

Re:Not ready for v6 yet (-1)

Anonymous Coward | about 3 months ago | (#47662027)

Will you pay for the switch? If not, leave the decision to those who will.

Re:Not ready for v6 yet (1)

BitZtream (692029) | about 3 months ago | (#47662193)

Some of us need a lot of self reflection :/

Re:Not ready for v6 yet (3, Insightful)

VGPowerlord (621254) | about 3 months ago | (#47663063)

If it weren't for the stupidity of OS and IP stack authors, we'd be able to use the 240.0.0.0 - 255.255.255.254 addresses.

However, most of them refuse to route to those addresses because they're "Reserved for Future use."

Apparently no one stopped to think that blocking routing to those addresses would stop them from being used in the future because people insist on using older technology.

IPv6 (0)

Anonymous Coward | about 3 months ago | (#47662009)

IPv6 will only make this worse, with more routes to be kept in a local routing table and more stuff cached in the TCAM tables.
The solution is the one Cisco gave them: buy a router that can accomodate more entries in that particular table. I'm sure they explored this option vs paying SLA penalties to whomever requests it.

Re:IPv6 (2, Informative)

Anonymous Coward | about 3 months ago | (#47662081)

You have no idea what you are talking about. Two words: prefix aggregation.

Re:IPv6 (1, Informative)

EvilJoker (192907) | about 3 months ago | (#47662167)

Why would that be different than with IPv4? Prefix aggregation, AKA route summary, AKA Supernetting, has been available for a very long time. Unless IPv6 addresses are being handed out in a way that's much more conducive to this, it won't really change anything. This guy agrees (#4) [cisco.com]

Further, since IPv6 is a longer address, fewer can be stored. Per Cisco [cisco.com] , the Catalyst 6500 can handle 1M IPv4 addresses, OR 512K IPv6 addresses (but not both simultaneously)

(Yes, I know the Catalyst is a switch, not a router, and the summary is bollocks for confusing the two. It was, however, the first mention of it I found)

Re:IPv6 (4, Informative)

Dagger2 (1177377) | about 3 months ago | (#47662219)

Unless IPv6 addresses are being handed out in a way that's much more conducive to this, it won't really change anything

Which they are, as a direct result of v6 being so huge. See RFCs 1715 and 3194 for discussion on this.

Obviously in the long run we'll end up with a higher absolute count of routes in v6 (because supporting more people was the other reason for it) but the route count will scale far better than a network that has to be run at a ridiculously high HD-ratio because it's too small.

Re:IPv6 (0)

Anonymous Coward | about 3 months ago | (#47662223)

Unless IPv6 addresses are being handed out in a way that's much more conducive to this... etc

They are, that's the whole point. You get your prefix from your upstream and they won't route anythhing else. If you change providers you change prefix, and IPv6 has specific provisions to facilitate that.

Re:IPv6 (2)

Geordish (751892) | about 3 months ago | (#47662299)

Why would that be different than with IPv4? Prefix aggregation, AKA route summary, AKA Supernetting, has been available for a very long time. Unless IPv6 addresses are being handed out in a way that's much more conducive to this, it won't really change anything. This guy agrees (#4) [cisco.com]

He is kinda correct, but the RIR's have come up with addressing plans to deal with this.
My info comes from the RIPE region, as its the region I'm in.

Every ISP gets assigned a /29 minimum. This is 2^35 networks (assuming you are using a /64 per network as recommended). If you prove you need more than a /29, fine, you can have it.

The next 3 bits are then reserved for future use. You use up your initial /29? Fine, increase your subnet mask to /28 and carry on. This doubles you address space. Carry on until you are at a /26. That is a LOT of room for growth.

In the IPv4 world this isn't possible. You get your allocation. You run out. You get another etc. Verizon are currently announcing 1,446 IPv4 prefixes from AS701, compared to the 12 IPv6 prefixes. Of the 12 IPv6 prefixes 5 of them are the one prefix they have deaggagated, the rest are customers with PI space.

You have a point about the near term, but long term once IPv4 has died a death (10+ years) the routing table will shrink again.

Re: IPv6 (1)

jrumney (197329) | about 3 months ago | (#47662429)

In the early days IPv4 addresses were handed out in a way that kept routing tables simple, but some time about 10 or 15 years ago we started to run out of blocks that were in the right range, so started allocating them all over the place. It will take us several lifetimes to get to that stage with IPv6.

Re:IPv6 (0)

Anonymous Coward | about 3 months ago | (#47662271)

Obviously you don't either.

Implementing IPv6 will not mean that IPv4 disappears by magic. It will stick with us for a long long time. So no, although aggregation is already happening, it will not solve the resource problems we have with routers.

I thought you overpaid for Cisco stuff (1)

Anonymous Coward | about 3 months ago | (#47662035)

just to avoid problems like this.

Obsolete? (1)

The New Guy 2.0 (3497907) | about 3 months ago | (#47662041)

We seem to have a bunch of things failing somewhat on the same day... is Cisco effectively saying "We're taking back what you have... please pay more!"?

Not really to do with "BGP" or "IPv4" as such... (3, Interesting)

cardpuncher (713057) | about 3 months ago | (#47662055)

This isn't really to do with BGP or IPv4 as such, it's an inherent problem in the way "The Internet" regards addresses.

You might be able to get some efficiencies in IPv6 by incorporating formerly-unrelated address allocations under a single prefix. But that doesn't solve the problem of a continuously growing network, increasingly complex (and commercially controversial) peering arrangements, the fact that IPv6 addresses are actually larger and the fact that you're going to have to support IPv4 anyway in parallel with any IPv6 transition (I don't personally believe it will ever happen, but that's a different story).

You could, however, get rather more efficiency in core routing tables if network addresses only had a very transient existence and were related to the source/destination route to be employed (eg: look up a domain name, do some route pre-computation, allocate some addressing tokens that make sense to the routers on the path, recalculate the route periodically or in response to packet loss). That's not IPv6, though. IPv6 has the same order of dependence on every router knowing about every destination network as IPv4 does (give or take the slightly greater prefixing efficiency).

TL;DR - The Internet is getting bigger. Buy more kit.

IPv6 would make the problem worse (0)

Anonymous Coward | about 3 months ago | (#47662073)

It uses 128 bit addresses instead of 32 bit addresses. And it does not officially support subnetting or hierarchical routing, although somewhere in the flood of IPv6 RFCs (there are dozens and dozens, most of which are at least partly deprecated) there might be some specification for somethat like that which is being ignored.

Re:IPv6 would make the problem worse (1)

Eravnrekaree (467752) | about 3 months ago | (#47662161)

Isnt subnetting more a software implementation DHCP, and BGP thing in the router, enter a net mask address and network address into the router config and then the router can analyse the addresses to determine if they are local or not. It seems, if IPV6 does not provide an equivalent for DHCP's getting the net mask then we are screwed. But net masks are not something you find in the IP packets headers themselves.

Re:IPv6 would make the problem worse (3, Insightful)

Dagger2 (1177377) | about 3 months ago | (#47662309)

v6 makes things better, because it uses 128-bit addresses rather than 32-bit addresses. See RFCs 1715 and 3194 for the details.

Yes, there's a small linear factor of extra memory required for v6 routes vs v4 routes, but that's irrelevant compared to the route count reduction that comes from a lower HD ratio.

Re:IPv6 would make the problem worse (2)

Paul Jakma (2677) | about 3 months ago | (#47662517)

There's no good reason to think there'll be a significant improvement in HD with IPv6, or significantly fewer prefixes advertised.

The issue is orthogonal to IPv6, it's fundamentally about how Internet routing is organised today. No hierarchy, and all prefixes must have global visibility. Hierarchical routing of the 90s has a bit of a bad name, and support for aggregation in BGP has been deprecated. However, there are things like topographical-landmark routing, which improve on the deficiencies of hierarchical routing. These would allow the Internet to grow without routing tables everywhere having to grow in direct proportion. Instead, routing tables wouldn't grow much at all, even as the Internet grew, in relative terms.

Re:IPv6 would make the problem worse (3, Insightful)

BitZtream (692029) | about 3 months ago | (#47662533)

but that's irrelevant compared to the route count reduction that comes from a lower HD ratio.

Only if you assume you can reduce routes because there are so many people with diverse blocks in their network, which isn't the case so much.

The route count is much more a result of multihoming and portable address space, which means larger prefixes aren't going to help at all. At no point in my career would my provider having a larger prefix helped reduce the routing table as I have always had either portable address space, which is a direct allocation from a NIC rather than an ISP, or been multi homed which means at best I get the addresses from ONE of the peers and announce it out to another peer, but in that case traffic gets all screwed up if the upstream provider which allocated me the non-portable space aggregates it since aggregated addresses aren't preferred over non-aggregated address space.

I.E. larger upstream prefixes don't really help at all.

Re:IPv6 would make the problem worse (2)

devman (1163205) | about 3 months ago | (#47662441)

In addition to the other points brought up by other posters. Routing decisions occur only on the first 64 bits of an IPv6 address. There is no need to store the entire address.

just ask carriers. (4, Interesting)

nimbius (983462) | about 3 months ago | (#47662075)

googling verizon, comcast, and time warner it seems like their original pledge in 2012 to start rolling out ipv6 has quietly halted. most of their sites simply say "check back" while others imply certain undisclosed service areas may be exposed to both 4 and 6. forums are another story, with most customers and techs confirming the support exists, but either modems arent enabled to receive ipv6 due to bugs, or the support is broken in all-in-one devices in the case of DSL.

speaking from a linux neckbeard standpoint, i dont care. ive had competent functional v6 support for almost a decade and in many cases implemented it for pay. In my experience the problems associated with implementing v6 are related to companies angry about any downtime at all, or vendor specific appliances that just cant for some reason or another. they either lied about their ipv6 support, only partially support routing IPv6, or have egregious bugs in their implementation that cause stability problems in the rest of the network. Hosting providers have done an excellent job of supporting it from what ive seen, and most (with the exception of godaddy) are very generous in their IP offerings (i get 30 with ramnode.)

Re:just ask carriers. (1)

Geordish (751892) | about 3 months ago | (#47662143)

Comcast are actually doing very well in this arena. http://corporate.comcast.com/c... [comcast.com] Their rollout plans are quite aggressive. John Brzozowski who works at Comcast gave an excellent presentation around 6 month ago in the UK about how they are rolling it out on their network. https://www.youtube.com/watch?... [youtube.com]

Re:just ask carriers. (0)

Anonymous Coward | about 3 months ago | (#47662963)

Except the part where they deliberately don't upgrade their end of the backbone interconnects, so they can make bandwidth a false scarcity.

Re:just ask carriers. (0)

Anonymous Coward | about 3 months ago | (#47662149)

I'm on Comcast in the DC area and I seem to get IPv6 just fine with a Motorola Modem and an Airport Extreme.

Re:just ask carriers. (0)

Anonymous Coward | about 3 months ago | (#47662381)

Comcast here in the Silicon Valley supports IPV6. I don't recall any fanfare about it when it hit my area (probably because unlike "doubling speeds", it's not very sexy and 99+% of their customers in most areas would have no idea what IPV6 is) so I have no idea when it became available (I've had Comcast for over ten years, so obviously it became active after I was subscribing).

Re:just ask carriers. (0)

Anonymous Coward | about 3 months ago | (#47662957)

I have Comcast and have had an IPv6 address from them for over a year now. I hate Comcast for many reasons, but lack of IPv6 ain't one of them.

Ipv6 to ipv4 interoperability is only way (0)

Eravnrekaree (467752) | about 3 months ago | (#47662077)

The fact is, TCP v6 was defective by design, because of what it does not have, and that is a mechanism for a long transition period between ipv4 and ipv6. If we had such transition period, ipv6 would now be widespread. The transition period means that ipv4 and ipv6 networks can communicate with each other. Making Ipv6 talk send packets to an ipv4 network is easy: give the ipv4 address block a subset of the ipv6 address block. The more complex but entirely doable part is ipv4->ipv6. Since ipv6 is larger address space than ipv4, ipv4 cannot directly see a lot of ipv6 addresses. The answer lies in the DNS system. When a user on an ipv4 network askes for the IP address associated with a DNS address which only has an ipv6 address associated with it, somewhere upstream, an upstream router and DNS server will conspire to 1) give the user (ipv4 peer) a fake IPv4 address for a DNS address 2) give the information on the ipv6 to fake ipv4 mapping to the router 3) which the router uses NAT to rewrite the packets headed out from from the fake ipv4 destination address to the real ipv6 destination address. Ipv6 packets headed in would be rewritten to ipv4 replacing the ipv6 source address with the fake ipv4 source address. Each ipv4 peer should be able to re-use the same block of ipv4 fake addresses, the mappings can be done on a per ipv4 peer (user) basis. Using this, its also possible to give ipv4 clients direct access to ipv6, using an .ipv6 DNS TLD, which can be used in the form .ipv6. You could even write an HTTP and other application protocol proxy that would automatically rewrite all ipv6 addresses in HTML with ipv6 TLD addresses. This makes ipv6 a upstream ISP thing rather than something that affects things on the users end, greatly simplifying things.ISPs as a complementary measure could also offer 6over4 gateways as well, and then over time transition to allowing raw ipv6 over their networks, a transition which can be gradual.

Re:Ipv6 to ipv4 interoperability is only way (1)

angryfeet (2876521) | about 3 months ago | (#47662135)

Yeah, I think 127.x.x.x would be good for temporary IPv6 mappings.

Re:Ipv6 to ipv4 interoperability is only way (1)

oodaloop (1229816) | about 3 months ago | (#47662329)

Can't figure out if you were going Insightful or Funny.

Re:Ipv6 to ipv4 interoperability is only way (1)

Eravnrekaree (467752) | about 3 months ago | (#47662479)

Theoritically, any block of Ipv4 addresses outside of the local subnet could be used, if an ipv4 address is used as a fake address, and then the user asks DNS address which happens to resolve to a real IPv4 address with the same number, then, the same NAT trick could be used with a mapping between created between another temporary local ipv4 address to the real internet ipv4 address which was already being used locally as a fake ipv4 number. Though, I would only recommend that be used as a fallback if 127.x.x.x is used up. A small part of the of RFC 1918 addreses could also be allocated for the pool of fake ipv4 address, such as maybe 172.20 and 172.21, giving a pool of 131072 ipv4 addresses, plenty for most use cases. I doubt most people will have that many TCP connections at once. Since 127 is not used for local networks, it is the best choice however as the first choice. Again, 127 is so large, i doubt most users would ever exhaust it, especially if the fake ipv4 mappings are timed out after a period of maybe 1 -7 days or so.

Re:Ipv6 to ipv4 interoperability is only way (0)

Anonymous Coward | about 3 months ago | (#47662173)

So you propose changes which would require a massive rollout of updates to equipment and infrastructure/protocol changes. Correct me if I am wrong but if we could manage to do that would we already be switched over to ipv6?

Re:Ipv6 to ipv4 interoperability is only way (1)

Eravnrekaree (467752) | about 3 months ago | (#47662989)

My solution is the one that would actually allow ISPs to gradually upgrade things over time rther than to replace everything at once, by allowing the interoperation. Its a lot easier if the changes are concentrated at the ISP end rather than effect subscribers as well. Its true that over time as due to the turnover of ipv4 older routers, that ISPs could gradually replace the subcribers routers with newer models. It would also be possible even for ISPs to collect older routers, flash them with new firmware, and put them back out, in the process of customer turnover cancellations and signups. The whole point is the solution i describe gives ISPs a transitiion period.

Re:Ipv6 to ipv4 interoperability is only way (2)

AndroSyn (89960) | about 3 months ago | (#47662185)

First of all, paragraphs are your friend.

Second of all, the solution you described already exists.
https://en.wikipedia.org/wiki/... [wikipedia.org]

On that same page, there are a bunch of other solutions as well, this has already been thought of :)

Re:Ipv6 to ipv4 interoperability is only way (1)

Anonymous Coward | about 3 months ago | (#47662217)

Yup, unless some sort of usable interoperability between IPv6 and IPv4 is thought up and rolled out, the transition will take a very long time. In fact, it might never even happen, and we'll just end up with two separate Internets!

The problem as stated is that IPv6 is NOT an upgrade to IPv4. Saying that it is would be like saying Windows is an upgrade for Solaris, or Linux is an upgrade for VMS. They are completely different things with no commonality at all.

This transition will be no different than moving from IPv4 to IPX/SPX or from Windows to VMS - You can't keep *anything* from IPv4, everything has to go.
The problem is, there is too much embedded infrastructure to just rip out all the old stuff and replace it, and a lot of old things don't have an IPv6-capable replacement.

This is the gigantic elephant in the room that is still being ignored, and until it is dealt with, people can harp on about address exhaustion as much as they like, but this transition will not happen; You will just have two incompatible networks running side by side.

Re:Ipv6 to ipv4 interoperability is only way (0)

Anonymous Coward | about 3 months ago | (#47662371)

The elephant is being ignored because it is not there. IPv6 provides the interoperabillity you ask for. I have no idea where you heard that FUD.

Re:Ipv6 to ipv4 interoperability is only way (1)

marka63 (1237718) | about 3 months ago | (#47662661)

Until there is sufficient IPv6 penetration that continuing to run IPv4 becomes pointless. If you turn on IPv6 on home networks over half the incoming traffic will be IPv6 traffic. Globally IPv6 is 4-6% IP traffic depending upon where you measure it. IP has replaced many networking protocols in the past. IPv6 will replace IPv4. The writing is already on the wall.

Many networks today are IPv6 only internally with protocol translation to talk to the legacy IPv4 Internet.

Other are dual stack translated to IPv6 only then translated back to dual stack on the Internet.

With IPv4 you are only going to get less and less functionality now that many ISP's are getting to the stage of having to deploy CGNAT. As a home user having a publicly reachable address will become a thing of the past.

No transition period? (1)

dbIII (701233) | about 3 months ago | (#47662333)

No transition period? We are about fifteen years into that transition period, and it has sucked immensely with things like the requirement of man in the middle stuff like Skype just to get VoIP to work on an internet infested with NAT.

Re:Ipv6 to ipv4 interoperability is only way (1)

rev0lt (1950662) | about 3 months ago | (#47662447)

I have no idea where you got that information. Check http://www.tcpipguide.com/free... [tcpipguide.com]

Hmm, the example on that page is interesting (1)

Marrow (195242) | about 3 months ago | (#47663047)

So the "compressed IPv6 address" has the low order bits used to reflect an IPv4 address. But I thought the low order bits were going to be MAC address bits in IPv6? The two seem inconsistent.

Oh, that explains things. (1)

eddy (18759) | about 3 months ago | (#47662115)

Probably why I couldn't reach NeoGAF for most of yesterday, unless I went through tor. Which I did, because I'm a man and I have my needs.

And how does IPv6 solve this issue? (1)

Sycraft-fu (314770) | about 3 months ago | (#47662145)

This is a real question: Do you know what IPv6 does instead of BGP? Because as far as I know, IPv6 is still using BGP, and that is what this is a problem with. In fact I can only see IPv6 making things worse in that regard because tons more address space means that more AS assignments would be easy to do.

So if it really does offer a solution, please enlighten me I'd be very interested. If this is just an example of trying to use a problem to push a favoured agenda, then please knock it off.

Re:And how does IPv6 solve this issue? (0)

Anonymous Coward | about 3 months ago | (#47662207)

Because the IPv6 address space is in theory large enough that aggregation is supposed to work correctly.

(Unfortunately all goes a bit down the toilet when everyone want's their own small chunk of PI address space, but it was originally intended that the aggregation would work more spoothly than in ipv4)

Re:And how does IPv6 solve this issue? (0)

Anonymous Coward | about 3 months ago | (#47662247)

So spooth you can eat it with a spoon ;)

Re:And how does IPv6 solve this issue? (1)

Vegard (11855) | about 3 months ago | (#47662563)

Address space is large enough unless we do something seriously fucked up. The IPv6 adress space has enough Ip-adresses that every atom of the surface of the earth can have 40.000 adresses.

Or, to divide it up a bit:

A "local network" will probably get a /64. This is *enough*, trust me, it's so much addresses that it can comtain the entire ipv4 address space - SQUARED. Noone will ever need more adresses than that in a local network.
A typical "end site" (a company, or even maybe a home user) would probably get a /48, or 65536 local networks. Again, *enough*.
An ISP would very often have one or perhaps several /32s. That means it can have 2^16 = 65536 "customers" who each have enough ip-adresses.

However, there are recommendations to limit the assignments for "home" users to /56. This makes for only 256 local networks in your home.

So if an ISP has a /32, we can imagine the following example:
Half of it, that is a /49, is allocated in /48 networks, allowing for 32768 corporate customers.
The other half of it is allocated in /56s, allowing for 32768*256 = 196608 home users.

Currently, one /3 is allocated to global unicast adress space. This gives space for 2^(32-3)=2^29 = roughly 534 million ISP allocations. Or, in another word, approximately one ISP per 10th of todays inhabitants in the world.

There are several /3s not yet allocated.

I guess there is enough.

Re:And how does IPv6 solve this issue? (1)

pla (258480) | about 3 months ago | (#47662721)

Yes IPv6 still uses BGP, but in a way that favors greatly reduced fragmentation.

Take a look at BellSouth's [he.net] list of announced prefixes for a pretty egregious example of this - Notice anything "funny" about it? They could reduce that list of almost 3000 down to under a hundred.

Re:And how does IPv6 solve this issue? (1)

marka63 (1237718) | about 3 months ago | (#47662731)

Multiple address, source address routing and multi path TCP will address lots of the reasons people want PI addresses today. IPv6 has enough addresses to make that mix of technologies a viable solution space. IPv4 is too resource constrained to make that a viable solution.

IPv6 won't fix this problem (2)

Paul Jakma (2677) | about 3 months ago | (#47662461)

This particular problem is due to the way routing on the Internet works, where generally every router must hold routes for every prefix announced on the Internet. That system doesn't change with IPv6. Now, there might be fewer IPv6 prefixes at this time than IPv4, but intrinsically there's nothing about IPv6 that addresses the problem that all prefixes must have global visibility.

To fix this kind of problem requires changing how routing is done.

SDN (1)

TheSync (5291) | about 3 months ago | (#47662607)

With SDN, an infinite number of prefixes can be stored on the SDN controller, and the Internet router only needs to load prefixes into the router TCAM when there is actually a flow needed for that prefix.

Re:SDN (0)

Anonymous Coward | about 3 months ago | (#47662871)

Sounds CPU intensive and slow.

We're the part that got dropped (1)

Phat_Tony (661117) | about 3 months ago | (#47662627)

We lost probably $30k in lost sales, and employees unable to do their jobs yesterday. Liquid web is going to lose a ton of customers over this. I don't know if it was their "fault," or if it was the top tier providers in their area they contract with. But as I understand it, if we had been with anyone really big who had us colocated in facilities way far away from each other, this would have been extremely unlikely.

IPv6 will never happen (0)

Anonymous Coward | about 3 months ago | (#47662649)

It's more likely a completely new/different Internet will be designed before IPv6 is ever widely adopted. It's just too difficult to use compared to IPv4. It has too many features that add complexity when trying secure networks. Plus the addresses are long and annoying to configure, etc.

IPv6 is to IPv4 as DVD-DL is to DVD.

Stop doing CIDR! (0)

Anonymous Coward | about 3 months ago | (#47662877)

And the problem goes away. The size of the routing tables is growing so much because every Tom, Dick, and Harry small business customer wants their own /29 block and certain ISPs like to serve those up using CIDR (are you lisetning to me, Comcast and Verizon?). This unnecessarily EXPLODES the size of the routing tables that everyone has to deal with.

Re:Stop doing CIDR! (3, Interesting)

BaronM (122102) | about 3 months ago | (#47663051)

OK, I've done BGP before, and I've never heard of anything smaller than a /24 being globally advertised -- most common router configurations won't even accept anything smaller.

That said, how is any network of any size supposed to protect itself again ISP outages other than multihoming? It clutters the routing table, but there is no other solution.

Is IPv6 "perfect" or will there be an IPv8? (2)

swb (14022) | about 3 months ago | (#47662999)

Given the time between IPv6 design and the eventual global adoption of it and abandonment of IPv4, will the broader adoption of IPv6 reveal problems addressed in a future revision?

I'll admit to being willfully ignorant of IPv6 other than seeing it as enormously more complicated than IPv4, trying to solve too many problems at once. I sometimes wonder if maybe IPv6 didn't appear so complicated and different that adoption might have been increased.

Couldn't they just have added a couple of extra bytes to IPv4 to come up with something that worked like IPv4? I also wonder about an addressing scheme like IPX, where a single network address covers an entire broadcast domain and node addresses are MAC addresses plus the network address. IPX network addresses were only 8 bytes, maybe that wouldn't be future proof enough (4.2 billion networks). I'm not talking about IPX as a protocol, just the system for addressing.

The advantage is relative simplicity (no need for DHCP, network addresses are discovered and the rest is built-in), broadcast domains can scale arbitrarily large without needing to renumber -- sure you can start out every network with a /16, but often they don't and there are complications in organizations just arbitrarily shifting masks past /24, such as running into other networks in the local routing domain.

Since node addresses are locally determined, ISPs would need to only assign a network address which would allow for basically unlimited public network addresses to each subscriber.

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