So, IPv6 has apparently been rolled out to me at home

[wintermute000]

supposed to be all /64 except for loopbacks but there is some debate about allowing /127s for p2p. I'm not sure if the latter has been ratified in an RFC or not. But its all a convention, I don't think technically there is anything stopping you from configuring a /49 or whatever, but any subnetting that's not contained within 16 (4 bits) is incomprehensible to the average human brain.


/64 = everything
/56 = supernet allocated to standard users
/48 = enterprise supernet allocation
/32 = small ISP allocation

be interested to see what depreciated means, at first glance they look like standard 2001:: routable addys.


<snark on> Yes, we'll have an infinite supply of addresses, but we've chosen such a difficult addressing scheme that the human brain can't process it unless we chop it in half arbitrarily, and also we can't manage to subnet except in blocks of 4 bits. <snark off>


https://en.wikipedia.org/wiki/IPv6_address#Temporary_addresses


Temporary addresses are the work of the freakin devil. Yes we can track your SLAAC MAC derived addy, deal with it. Oh why the f--k did they not just retain DHCP, and why the f--k did they design SLAAC but NOT INCLUDE DNS INFO ORIGINALLY (and... now add it back retrospectively?!?!?!? but now luck of the draw re: whether your host's ipv6 stack has been updated to use this feature and any sane larger org would use DHCPv6 anyway for manageability...... oh and the m flag is just a suggestion, not mandatory, ARE YOU KIDDING ME ). Seriously, so many WTF design decisions.

[Dieselboy]

Question:
The ISP my previous employer uses in London, England - they wanted us to have IPv6 so we said great! But they had some admin / config issues so I ended up leaving before it was provisioned. I'm pretty sure there was no costs involved as we were paying for the internet line.

Trying to think back, are IPv6 addresses free? Or supposed to be free?

My ISP here said there's no movement on IPv6 addressing cost.. I'm about to reply asking to break down the $32 a month cost then, since IPv6 addresses are free from the respective authority (I guess APNIC here in Australia). But I'm not sure if I'm correct.

Any ideas?

[wintermute000]

Provider independent is justlike ipv4, you register a block with APNIC. If you take the provider free one you're using a block out of their allocation and will have to change ALL YOUR ADDRESSING if you change ISP. Not an issue for standard home user or anything completely dynamic but for any substantial business it's worth having PI ipv6 /48

Another side effect of eliminating NAT that the boffins didn't quite think through....
I think they're working on something to fix this but unsure of progress. There's been a lot of arguments over this for sure.

If this has changed recently I'd love to be corrected

[Dieselboy]

I completely didn't think about the PI space, in England you normally only get that if you're running BGP to dual ISPs.

What I was talking about was the ISP in England saying "here you are, have a /64!" and there being no extra costs involved. Given your scenario, this was the same as any ISP saying, here's your /29.
But yes, regarding NAT, my ipv6 at home is not natted at all. So in 20 yrs time when IPv4 is depreciated, how does new companies set up their internal network on v6 when the addressing is dictated from the ISP? Or do we go to APNIC and ask "where's my companies v6 space? Bish"

And then what if I Set up ipv6 at home, with devices having static v6 addresses because they're doing something important - like a TV / Streaming device. I switch ISP's and my home network breaks?

[wintermute000]

This exact point has been raised numerous times in many ipv6 discussions, and the powers that be decided that NAT was evil and had to go, everything else be damned, so here we are.

Its related to the whole 'but how is any SMB without PI space going to multihome in ipv6 only' and the answer is 'everyone who needs it should get PI space and peer BGP'.

I suppose thinking holistically you'd want everything to be as DNS based as possible, but that begs the question of how you make your DNS servers dynamic (not too familiar with mDNS etc.)

[deanwebb]

Dynamic DNS records means hours of unavailability for an enterprise if their address changes and that has to replicate through the world. It's good if you have a tiny webserver and some patient buddies, but totally unacceptable for a major organization.

Thing is, if the Fortune 100 companies don't want IPv6 in its current version, it will be changed to where they'll be happy using it. If the cost of going to v6 is greater than paying a premium to keep a v4 address alive, the premium gets paid and the v4 stays on.

[srg]

Provider independent is justlike ipv4, you register a block with APNIC. If you take the provider free one you're using a block out of their allocation and will have to change ALL YOUR ADDRESSING if you change ISP. Not an issue for standard home user or anything completely dynamic but for any substantial business it's worth having PI ipv6 /48

Another side effect of eliminating NAT that the boffins didn't quite think through....
I think they're working on something to fix this but unsure of progress. There's been a lot of arguments over this for sure.

If this has changed recently I'd love to be corrected

#1 if course is get your own PI. If you're big enough that renumbering is a major task, it's probably worth it.
There's also the option of ULA and 1:1 NATv6.

Also as mentioned, DNS will be more important.

[Dieselboy]

It just seems a bit of a mess?

Before I left on Friday I was looking up IPv6 design guides on IP address allocations, found some good stuff but 5pm came.

I could use the private address space now, fc00:: to fd00:: - fd00:FFF...., these are the equivalent of 192.168.x.x, but I really need to find out what the pro's and con's are for doing such a thing.
May be one "pro" would be that your internal network device etc management IP's could be on the non internet routable IPv6s. You could say you would never want to access the management IP of a switch, from the internet (example).. But then I guess you would end up with management VLANs on private address space, and VLANs for desktops which would use IP addresses to get out to the internet.

Does anyone have any case studies or white papers for documented designs relating to IPv6?

The funniest thing was realising what wintermute said, yesterday; about changing ISPs and your home or even office network breaks. haha - this made my weekend.

[Dieselboy]

Oh, and no benefits for the moment for IPv6 really. In fact, as much as I like new stuff and IPv6, I still feel a network behaver better on IPv4 only. But that can't last of course.

I was seeing this too. I was seeing v4 preferred over v6 as well for an unknown reason at one time (bug in Windows somewhere..)..

I've recently swapped out my own Cisco 877 for the ISP router, so I can get 802.11n and allow any and all traffic inbound to hit my games console. I don't know how long ive been IPv6 enabled, but no issues so far. Things are pretty fast. I'm also using windows 10.
But, I have been confused as to why videos on facebook buffer on my mobile phone. I just assumed someones wifi was interfering again (2.4ghz is crowded in our block of apartments, and people don't know how to set them up (max strength, most using the same channel)).
Maybe, theres a bit of slowness somewhere or my phone doesn't fully like v6 yet. I just did a whats my ip from the phone and it has a v6 address.

[srg]

The funniest thing was realising what wintermute said, yesterday; about changing ISPs and your home or even office network breaks. haha - this made my weekend.

For home I don't see this as a big problem. There are stuff to make this easier, like the general prefix; http://www.cisco.com/c/en/us/td/docs/ios-xml/ios/ipv6_basic/configuration/15-mt/ip6b-15-mt-book/ip6-generic-prefix.html

For offices though, this might be more of a hassle.

[wintermute000]

This is a good start for enterprise, a bit dated

http://www.cisco.com/c/en/us/td/docs/solutions/Enterprise/Campus/CampIPv6.html

[Reggle]

An IPv6 subnet is de facto always a /64. You're free to do oherwise but it will break SLAAC/EUI-64 so it's not wise. I'm assuming Windows either assumes /64 or only understands /64 as the reason to why it's not showing.
No idea why an address is preferred or deprecated. In fact, Ivan has blog posts about address allocation and source address selection and both are rants about the unclarity of it.
I can explain the temporary part though: Windows uses IPv6 address randomization by default and will regularly choose another IPv6 address in the subnet. This is actually a good thing, otherwise the MAC address will be visible in the IPv6 address and it will stay visible when changing to another subnet, allowing for easy tracing.

[Dieselboy]

An IPv6 subnet is de facto always a /64. You're free to do oherwise but it will break SLAAC/EUI-64 so it's not wise. I'm assuming Windows either assumes /64 or only understands /64 as the reason to why it's not showing.

Oh yea, Doh! I didn't think of that.

[routerdork]

So I've got my IPv6 working now thanks to this article. In the comments someone explains how they setup their Cisco router and how they set it up to receive a /56. Very close to what I had originally.
https://major.io/2014/09/11/howto-time-warner-cable-ipv6/

Code Select Expand

interface GigabitEthernet0/0
description Uplink to: Time Warner Cable
ipv6 address dhcp
ipv6 address autoconfig default
ipv6 enable
ipv6 dhcp client pd hint ::/56
ipv6 dhcp client pd TWC-Prefix


My biggest issue was that I had a static route from the HE.net tunnel that I had moved from my tunnel interface to my outside (TWC) interface. With that in place IPv6 couldn't reach the gateway due to them using a /128 to setup the connection. So once I removed that the default was placed in my table from TWC and all works. I can reach the Googles on IPv6. 

[Dieselboy]

Nice! And thanks for the link too!