Re: [radext] Alissa Cooper's Discuss on draft-ietf-radext-ip-port-radius-ext-11: (with DISCUSS and COMMENT)

[Kathleen Moriarty <[e-mail]>]

On Fri, Oct 14, 2016 at 11:42 AM, Alan DeKok <[e-mail]>
wrote:

>
> > On Oct 14, 2016, at 11:16 AM, <[e-mail]> <
> [e-mail]> wrote:
> > Can you elaborate a little bit?
> > What do you call 'appropriate parent TLV'?
>
>   The idea is that if you have a TLV, it can:
>
> a) define it's own sub-TLVs
>
> b) use a pre-defined registry for sub-TLVs.
>
>   That's it.
>
>   If a TLV is defined to use option (a), there's no conflict with other
> TLVs.  It's sub-TLVs are completely independent of all other sub-TLVs.  And
> it *cannot* use TLVs from a registry.
>
>   If a TLV is defined to use option (b), then it *cannot* define it's own
> sub-TLVs.  It MUST use the registry.  Which means re-using sub-TLVs from
> the registry.  Because that's what registries are for.
>
>   sub-TLVs defined in a registry can't conflict with other sub-TLVs,
> because each TLV space is entirely independent... unless you define them to
> overlap.
>
> > If a registry is defined to track allocated value for sub-TLV, how to
> avoid collision if "All other TLV parents are free to specify whatever
> sub-TLVs they want".
>
>   That question is based on assumptions I don't understand.  As such, it
> can't really be answered other than with "it doesn't work like that".
>
>   If we have a registry, fine.  Use it.  If we don't have a registry, then
> attributes not using the registry... don't use the registry.  And there's
> no conflict.  Because they're not using the registry.
>
>   There is no more conflict here than with Service-Type and
> Framed-Protocol.  Both are "integer" attributes.  Both define a registry.
> But adding an entry to Service-Type doesn't mean that that number is now
> also defined for Framed-Protocol, much less have any special meaning for
> any other "integer" attribute.
>
>   Perhaps you could explain why you think there would be any conflict
> between sub-TLVs?
>

It seems the WG is just down to a preference question as I don't see how
there would be conflicts except if different parties defined their own
sub-TLVs and they didn't match.  Could that occur?  I have to dig deeper to
make sure I'm not missing anything.

For the future, you can ask IANA these sorts of questions via email or at
meetings to work through preferences if you are looking for their opinion.
I should have caught that this was an issue and am not sure why I didn't
before putting it on a telechat.  So, that was my fault.

Thank you.

>
>   Alan DeKok.
>
>


-- 

Best regards,
Kathleen