[186500] in North American Network Operators' Group
Re: Nat
daemon@ATHENA.MIT.EDU (Daniel Corbe)
Sun Dec 20 12:55:40 2015
X-Original-To: nanog@nanog.org
From: Daniel Corbe <dcorbe@hammerfiber.com>
In-Reply-To: <1356977108.3953.1450630744338.JavaMail.mhammett@ThunderFuck>
Date: Sun, 20 Dec 2015 12:55:34 -0500
To: North American Network Operators' Group <nanog@nanog.org>
Errors-To: nanog-bounces@nanog.org
> On Dec 20, 2015, at 11:57 AM, Mike Hammett <nanog@ics-il.net> wrote:
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> 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.=20
EUI-64 isn=E2=80=99t the only thing out there that expects hosts to have =
64-bit addresses. That was only an example. =20
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> There may be address space to support it, but is there nimble boundary =
space for it?=20
Yes. Do the math. If every end user got a /48 there=E2=80=99s 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=E2=80=99ll see =
281 trillion people walking around any time in the next 1000 generations =
of human civilization. =20
IPv6 is here to stay. =20
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> 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?=20
You=E2=80=99re still stuck on =E2=80=9CLOOOOL ADDRESSES.=E2=80=9D =20
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> 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.=20
There isn=E2=80=99t going to be a next time.
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> -----=20
> Mike Hammett=20
> Intelligent Computing Solutions=20
> http://www.ics-il.com=20
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> ----- Original Message -----
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> From: "Daniel Corbe" <corbe@corbe.net>=20
> To: "Mike Hammett" <nanog@ics-il.net>=20
> Cc: "Mark Andrews" <marka@isc.org>, "North American Network Operators' =
Group" <nanog@nanog.org>=20
> Sent: Saturday, December 19, 2015 10:55:03 AM=20
> Subject: Re: Nat=20
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> Hi.=20
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>> On Dec 19, 2015, at 11:41 AM, Mike Hammett <nanog@ics-il.net> wrote:=20=
>>=20
>> "A single /64 has never been enough and it is time to grind that=20
>> myth into the ground. ISP's that say a single /64 is enough are=20
>> clueless."=20
>>=20
>>=20
>>=20
>> LLLLOOOOOOLLLLL=20
>>=20
>>=20
>> 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.=20
>>=20
>>=20
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> You=E2=80=99re being deliberately flippant.=20
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> 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.=20
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> The requirement for the host portion of the address to be 64 bits long =
isn=E2=80=99t 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.=20
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> Handing out a /56 or a /48 allows the customer premise equipment to =
have multiple networks behind it. It=E2=80=99s a good practice and =
there=E2=80=99s certainly enough address space available to support it.=20=
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