AT&T UVERSE Native IPv6, a HOWTO

Ricky Beam jfbeam at gmail.com
Mon Dec 2 21:25:27 UTC 2013


On Fri, 29 Nov 2013 08:39:59 -0500, Rob Seastrom <rs at seastrom.com> wrote:
> So there really is no excuse on AT&T's part for the /60s on uverse 6rd...

Except for a) greed ("we can *sell* larger slices") and b) demonstrable  
user want/need.

How many residential, "home networks", have you seen with more than one  
subnet?  The typical household (esp Uverse) doesn't even customize the  
provided router.  Even a CCIE friend of mine has made ZERO changes to his  
RG -- AT&T turned off WiFi and added the static block at install. (I know  
NANOG is bad sample as we're all professionals and setup all kinds of  
weird configurations at "home". I have 3 nets in continuous use... a  
legacy public subnet from eons ago (I never renumbered), an RFC1918 subnet  
overlapping that network (because it's too small), and a second RFC1918  
net from a second ISP)

I wouldn't use the word "generous", but a /60 (16 "LAN"s) is way more than  
what 99% of residential deployments will need for many years.  We've  
gotten by with a single, randomly changing, dynamic IP for decades.  Until  
routers come out-of-the-box setup for a dozen networks, non-networking  
pros aren't going to need it, or even know that it's possible. (and the  
default firewalling policy in Windows is going to confuse a lot of people  
when machines start landing in different subnets can "see" each other.)

Handing out /56's like Pez is just wasting address space -- someone *is*  
paying for that space. Yes, it's waste; giving everyone 256 networks when  
they're only ever likely to use one or two (or maybe four), is  
intentionally wasting space you could've assigned to someone else. (or  
**sold** to someone else :-)) IPv6 may be huge to the power of huge, but  
it's still finite. People like you are repeating the same mistakes from  
the early days of IPv4... the difference is, we won't be around when  
people are cursing us for the way we mismanaged early allocations.   
Indeed, a /64 is too little (aka "bare minimum") and far too restrictive,  
but it works for most simple (default) setups today. Which leads to DHCPv6  
PD... a /60 is adequate -- it's the minimal space for the rare cases where  
multiple nets are desirable or necessary. The option for /56 or even /48  
should exist (esp. for "business"), but the need for such large address  
spaces are an EXCEPTION in residential settings. (and those are probably  
non-residential users anyway.) [FWIW, HE.net does what they do as  
marketing. And it works, btw.]



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