Re: [v6ops] draft-moreiras-v6ops-rfc3849bis-00

[Owen DeLong <[e-mail]>]

On Aug 13, 2013, at 12:58 , "George, Wes" <[e-mail]> wrote:

> 
> 
> 
>> -----Original Message-----
>> From: Owen DeLong [mailto:[e-mail]]
>> Sent: Tuesday, August 13, 2013 2:29 PM
>> To: George, Wes
>> Cc: Antonio M. Moreiras; [e-mail]
>> Subject: Re: [v6ops] draft-moreiras-v6ops-rfc3849bis-00
>> 
>> 
>> 
>> The original proposal for a larger doc prefix is all about being able to
>> write books and training scenarios that use a doc prefix and talk about
>> carving up larger chunks of address space.
> [WEG] The thing I don't understand about that is how carving x subnet blocks out of a /32 is different from carving x blocks out of a /48 or x blocks out of a /20 or whatever you start with as it concerns documentation. Other than the prefix lengths being somewhat longer, the examples of how to subnet, how to configure routing, etc still hold, don't they? AFAICT, as long as you don't end up subnetting below /64, there's really no issue. Yes, real routing policy likely won't pass a bunch of /64s, but for a lab such as what you detailed, and the subtending documentation that should work just fine, no? Especially given that the goal is to teach someone how to do something, instead of simply giving them something to copy with no understanding of what it's doing.

You and I know that it isn't. For the ab initio student, it's one more difference in the overwhelming pile of things being poured into their brain.

Trust me, while it isn't different for someone with experience, in my experience, it drives students crazy and they get wrapped around the axle on the differences in the examples and lose sight of what is being taught.

> For ab initio training,
>> trying to teach students that these ULA examples are not really
>> applicable to ULA, but should be used with GUA is very confusing and it
>> really does break their brains. Allocating a larger doc prefix would
>> help with this scenario a lot.
> [WEG] A point I'll concede, and one that should make it into the draft. :-)
> 
>> 
>> Secondarily, I mentioned that while we were considering an additional
>> doc prefix, it might make sense to also look at allocating a third doc
>> prefix for creating ULA examples. I think this should come from the
>> fc00::/8 space which is currently unusable  anyway, and which would
>> allow examples describing the use of (and reasons not to use) ULA with a
>> prefix that would be easily identified if the examples were erroneously
>> copied into the real world.
>> 
>>>> I would prefer to choose an arbitrary prefix, inside or outside
>>>> 2000::/3, but that "looks like" a GUA, than use ULAs in the classes.
>>> [WEG] Might I suggest repurposing all or part of 0200::/7? (RFC4048).
>> Even if we don't officially allocate it as additional documentation
>> space, that seems a safe squat point for things like training, likely to
>> already be filtered by SPs as bogon space, etc.
>> 
>> Works for me.
>> 
>> I would suggest 0200:2000::/20 to fit with the other requestors' desire
>> for a /20. For my needs, even 0200:2200::/24 would be adequate.
>> 
> 
> [WEG] at the risk of debating bikeshed colors, I would suggest perhaps using :db8:: for both the proposed GUA and ULA doc prefixes so that it serves as a visual cue.

I have no problem with that.

How about 02db:8000::/20 and fc00:0db8::/32?

Owen

P.S. love the disclaimer disclaimer.