On Tue, Feb 21, 2017 at 5:44 PM, Brian E Carpenter <brian.e.carpenter@xxxxxxxxx> wrote:
On 21/02/2017 23:13, Job Snijders wrote:
> On Tue, Feb 21, 2017 at 02:11:15PM +1300, Brian E Carpenter wrote:
>> On 21/02/2017 13:19, Job Snijders wrote:
>>> On Thu, Feb 16, 2017 at 09:40:01AM +0100, otroan@xxxxxxxxxxxxx wrote:
>>>> There are many reasons for the 64 bit boundary.
>>>> - Allowing identifier locator split: 8+8 / GSE that led to ILNP and NPT66
>>>
>>> Irrelevant.
>>
>> Not really. They are both running code. You may not want them in
>> *your* network but that isn't the point. Some people want them.
>>
>> And there is a lot of other running code too, not just SLAAC which is
>> mandatory to implement in every IPv6 host. So this actually trumps all
>> the other arguments: it's 64 bits because it's 64 bits.
>
> When someone utters the phrase "it is X because it is X", the rhetorical
> imperative seems to be to dismiss further conversation (perhaps any
> internal dialogue as well, which may be the primary purpose). "It is
> what it is" therefore, there’s nothing more to be said about it...
>
> Except when it's not 64 bits?
That wasn't quite my intention. I just wanted to underline that
(like it or not) it was set at 64 bits many years ago and a lot
has been built on that.
I think one of the points the thread has brought out is that: "just because we have always been at war with elbonia, does not mean we have to keep being at war with elbonia"
We don't have to keep promulgating advice that we don't actually use in practice... If we set the "Internet Standard" today we can move forward to a better world in the time it takes to age out old 'broken' gear/software... (yes, that's a while but eventually :) )
...
> I've looked at all configured IPv6 addresses on AS 2914 equipment.
> Interestingly enough, the below table is a reflection of not only NTT's
> own addressing, and (since AS2914's core function is to connect networks
> to each other) also of its peers and customers. In the end, whatever
> makes the thing work is the thing that will be configured.
>
> /127 - 22%
> /126 - 52%
> /125 - 0,9%
> /124 - 0,5%
> /120 - 0,04%
> /112 - 0,02%
> /64 - 23%
Thanks, that's interesting. So 23% of the devices might have
RFC4291-compliant IIDs. The others are configured with 128 bit
IPv6 addresses. Is that correct?
That being so, perhaps the words that are missing are
"The IID length requirement does not apply to interfaces that
are explicitly configured with 128 bit addresses." Because the
requirement is meaningless for such interfaces.
specifying the 128 here seems wrong... or I'm using it wrong in my interpretation :)
I would have said:
"The IID length requirement does not apply to interfaces that are explicitly configured."
"The IID length requirement does not apply to interfaces that are explicitly configured."
all ipv6 interfaces have 128 addresses, they may have a subnet configuration which is shorter though. right?