Re: Nat

[Daniel Corbe <dcorbe () hammerfiber com>]

> On Dec 20, 2015, at 11:57 AM, Mike Hammett <nanog () ics-il net> wrote:
>
> However, keeping back 64 bits for the host was a stupid move from the beginning. We're reserving 64 bits for what's 
> currently a 48 bit number. You can use every single MAC address whereas IPS are lost to subnetting and other such 
> things. I could have seen maybe holding back 56 bits for the host if for some reason we need to replace the current 
> system of MAC addresses at some point before IPv6 is replaced. 

EUI-64 isn’t the only thing out there that expects hosts to have 64-bit addresses.  That was only an example.  

> There may be address space to support it, but is there nimble boundary space for it? 

Yes.  Do the math.  If every end user got a /48 there’s still 281 *trillion* subnets to go around.   The limiting 
factor in IPv4 is that nobody expected to be able to connect 4 billion devices to the Internet when it was conceived.  
I really doubt that we’ll see 281 trillion people walking around any time in the next 1000 generations of human 
civilization.  

IPv6 is here to stay.  

> The idea that there's a possible need for more than 4 bits worth of subnets in a home is simply ludicrous and we have 
> people advocating 16 bits worth of subnets. How does that compare to the entire IPv4 Internet? 

You’re still stuck on “LOOOOL ADDRESSES.”  

> There is little that can be done about much of this now, but at least we can label some of these past decisions as 
> ridiculous and hopefully a lesson for next time. 

There isn’t going to be a next time.

> ----- 
> Mike Hammett 
> Intelligent Computing Solutions 
> http://www.ics-il.com 
>
> ----- Original Message -----
>
> From: "Daniel Corbe" <corbe () corbe net> 
> To: "Mike Hammett" <nanog () ics-il net> 
> Cc: "Mark Andrews" <marka () isc org>, "North American Network Operators' Group" <nanog () nanog org> 
> Sent: Saturday, December 19, 2015 10:55:03 AM 
> Subject: Re: Nat 
>
> Hi. 
>
> > On Dec 19, 2015, at 11:41 AM, Mike Hammett <nanog () ics-il net> wrote: 
> >
> > "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." 
> >
> >
> >
> > LLLLOOOOOOLLLLL 
> >
> >
> > A 100 gallon fuel tank is fine for most forms of transportation most people think of. For some reason we built IPv6 
> > like a fighter jet requiring everyone have 10,000 gallon fuel tanks... for what purpose remains to be seen, if ever. 
>
> You’re being deliberately flippant. 
>
> There are technical reasons why a single /64 is not enough for an end user. A lot of it has to do with the way auto 
> configuration works. The lower 64 bits of the IP address are essentially host entropy. EUI-64 (for example) is a 64 
> bit number derived from the mac address of the NIC. 
>
> The requirement for the host portion of the address to be 64 bits long isn’t likely to change. Which means a /64 is 
> the smallest possible prefix that can be assigned to an end user and it limits said end user to a single subnet. 
>
> Handing out a /56 or a /48 allows the customer premise equipment to have multiple networks behind it. It’s a good 
> practice and there’s certainly enough address space available to support it.