Re: [mpls] Last Call: <draft-ietf-mpls-spl-terminology-03.txt> (Special Purpose Label terminology) to Informational RFC

[tom petch <[e-mail]>]

On 23/08/2020 21:47, Adrian Farrel wrote:
> Hi Tom,
>
> You're right (a condition that must be scarily familiar for you).
>
> Probably...
>
> OLD
>     o  Collectively, the two ranges are known as Special Purpose Labels
>        (SPL).
>
>     o  The special purpose labels from the lower range will be called
>        Base Special Purpose Labels (bSPL).
>
>     o  The special purpose labels from the higher range will be called
>        Extended Special Purpose Labels (eSPL).
> NEW
>     o  Collectively, the two ranges (0-15, and 16-1048575) are known
>         as Special Purpose Labels (SPL).
>
>     o  The special purpose labels from the lower range (0-15) will be
>         called Base Special Purpose Labels (bSPL).
>
>     o  The special purpose labels from the higher range (16-1048575)
>          will be called Extended Special Purpose Labels (eSPL).  The
>          reserved values 0-15 from the 'Extended Special-Purpose MPLS
>          Label Values' registry do not need a name as they can never be
>          used.
> END

Yes, clearer.

Perhaps
"       The
     reserved values 0-15 from the 'Extended Special-Purpose MPLS
     Label Values' registry do not need a name as they are not available 
for allocation. "
to tie in with the wording of IANA.  They SHOULD NOT or MUST NOT be used 
but I can see some independent-minded organisation deciding that because 
noone else will ever use them then they can and they will so I think 
'can never be used' is not quite right.  They can never be allocated so 
we do not need an identifier for them, which is what I am wanting to 
express.

I note that this is Informational and so RFC2119 language is best avoided.

Tom Petch

> Best,
> Adrian
>
> -----Original Message-----
> From: tom petch <[e-mail]>
> Sent: 19 August 2020 17:25
> To: [e-mail]
> Cc: [e-mail]; [e-mail]; [e-mail];
> [e-mail]
> Subject: Re: Last Call: <draft-ietf-mpls-spl-terminology-03.txt> (Special
> Purpose Label terminology) to Informational RFC
>
> I find this confusing.
>
> It specifies two ranges 0-15 and 0-1048575 the latter being subdivided
> into ranges 0-15 16-239 etc and then talks of the lower range and the
> higher range; is the higher range 0-1048575 or 16-239 or 16-1048575 or ...?
> Lesser and greater or first and second or smaller and larger .. I might
> find unambiguous but reading this with an innocent eye, I find higher
> ambiguous.
>
> And in Security, 'It does not effect the forwarding ...' Well, no, it
> would likely not affect it either:-)
>
> Tom Petch
>
>
>
> On 12/08/2020 19:48, The IESG wrote:
>>
>> The IESG has received a request from the Multiprotocol Label Switching WG
>> (mpls) to consider the following document: - 'Special Purpose Label
>> terminology'
>>     <draft-ietf-mpls-spl-terminology-03.txt> as Informational RFC
>>