Mark Andrews marka at
Mon Dec 21 03:40:50 UTC 2015

In message <[email protected]>, "Chuck Church" writes:
> -----Original Message-----
> From: Mark Andrews [mailto:marka at] 
> Sent: Thursday, December 17, 2015 7:46 PM
> To: Chuck Church <chuckchurch at>
> Cc: 'Matthew Petach' <mpetach at>; 'North American Network
> Operators' Group' <nanog at>
> Subject: Re: Nat
> >I have a single CPE router and 3 /64's in use.  One for each of the
> wireless SSID's and one for the wired network.  This is the default for
> homenet devices.  A single /64 means you >have to bridge all the traffic.
> >A single /64 has never been enough and it is time to grind that myth into
> the ground.  ISP's that say a single /64 is enough are clueless.
> Mark,
> 	I agree that a /48 or /56 being reserved for business
> customers/sites is reasonable.  But for residential use, I'm having a hard
> time believing multi-subnet home networks are even remotely common outside
> of networking folk such as the NANOG members.  A lot of recent IPv4 devices
> such as smart TVs have the ability to auto-discover things they can talk to
> on the network.  If we start segmenting our home networks to keep toasters
> from talking to thermostats, doesn't this end up meaning your average home
> user will need to be proficient in writing FW rules?  Bridging an entire
> house network isn't that bad.

So *you* think the ISPs should *dictate* how a user internally
splits up their network?  There is NO technical reason to NOT give
a customer multiple subnets.  Every technology supports multiple
prefixes. Even with 6rd you *can* give the user multiple subnets.
It's only lazyness (or purchasing incompetence if the BR doesn't
support multiple domains) that results in ISP's handing out single
subnets over 6rd.

> Chuck
Mark Andrews, ISC
1 Seymour St., Dundas Valley, NSW 2117, Australia
PHONE: +61 2 9871 4742                 INTERNET: marka at

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