[131141] in North American Network Operators' Group
=?windows-1252?Q?Re:_IPv6_fc00::/7_=97_Unique_local_addresses?=
daemon@ATHENA.MIT.EDU (Owen DeLong)
Wed Oct 20 20:44:14 2010
From: Owen DeLong <owen@delong.com>
In-Reply-To: <4CBF8782.2040301@mompl.net>
Date: Wed, 20 Oct 2010 17:41:52 -0700
To: Jeroen van Aart <jeroen@mompl.net>
Cc: NANOG list <nanog@nanog.org>
Errors-To: nanog-bounces+nanog.discuss=bloom-picayune.mit.edu@nanog.org
On Oct 20, 2010, at 5:21 PM, Jeroen van Aart wrote:
> Deepak Jain wrote:
>> According to the RFC:=20
>=20
>> 3.2.1. Locally Assigned Global IDs
>> Locally assigned Global IDs MUST be generated with a pseudo-random
>> algorithm consistent with [RANDOM]. Section 3.2.2 describes a
>=20
>> Global ID in this case means the 40 bit pseudo random thing. The =
point here is, we are all supposed to pick our own poison and pray that =
we are unique. Though an algorithm is suggested in 3.2.2. Perhaps SIXXS =
uses it. Anyway, the SIXXS tool seems pretty slick.
>=20
> All thanks for the information. I'll be using the "40 bit pseudo =
random thing" since it seems to be the smart thing to do, using the =
SIXXS tool. One may hope that something will become the "official" way =
to generate these numbers (perhaps the above mentioned tool).
>=20
I believe the above mentioned tool uses the OFFICIAL way documented in =
the RFC.
There is an official way to do it. It is documented in the RFC.
> Someone advised me to use GUA instead of ULA. But since for my =
purposes this is used for an IPv6 LAN would ULA not be the better =
choice?
>=20
IMHO, no. There's no disadvantage to using GUA and I personally don't =
think ULA really serves a purpose. If you want to later connect this
LAN to the internet or something that connects to something that =
connects to something that connects to the internet or whatever, GUA =
provides
the following advantages:
+ Guaranteed uniqueness (not just statistically probable =
uniqueness)
+ You can route it if you later desire to
Since ULA offers no real advantages, I don't really see the point.
Owen
