> On Mar 11, 2020, at 6:13 AM, Peter Psenak <[email protected]> wrote:
> 
> On 11/03/2020 09:24, Christian Hopps wrote:
>>> On Mar 10, 2020, at 8:06 PM, Les Ginsberg (ginsberg) 
>>> <[email protected]> wrote:
>>> 
>>> Chris/Acee -
>>>  I strongly agree with Peter.
>>>  There is no point in creating a protocol specific registry for behavior 
>>> values which are protocol agnostic.
>>> This only adds duplication (which is NOT the same as redundancy 😊 ).
>> This was and is not my suggestion.
>>> What I find unfortunate is that the table in Section 10 of 
>>> draft-ietf-lsr-isis-srv6-extensions-06.txt  has a "Behavior Endpoint 
>>> Codepoint" column. That should be removed.
>> Or remove the names and just leave the values, whatever, since mapping names 
>> or registering values isn't the point of the table you could do either.
>>> The legal behaviors to be advertised by IS-IS are then defined by name in 
>>> column 1.
>> This table isn't "the legal value to be advertised in IS-IS" it's "Which 
>> sub-TLV in IS-IS are allowed to advertise a given behavior value". Again 
>> this table looks just like other IS-IS sub-TLV registries where we list 
>> which values are allowed in which TLV.
>> To be clear here *IF* SR were an IS-IS only thing we would have a registry 
>> that looked like this:
>> ** IF SR were only an IS-IS thing **
>> | Value | Description    | [End] | [End.X] | [LAN End.X] | Reference |
>> | A     | Behavior A     | Y     | N       | N           | RFC-A000  |
>> | B     | Behavior B     | N     | Y       | Y           | RFC-B000  |
>> | C     | New Behavior C | Y     | N       | N           | RFC-C000  |
>> | ...   | ...            |       |         |             |           |
>> But it's not, so we have protocol agnostic SR behaviors
>> ** SR (protocol agnostic -- already exists) **
>> | Value | Name/Description | Reference   |
>> | A     | Behavior A       | SR-RFC-A111 |
>> | B     | Behavior B       | SR-RFC-B111 |
>> | C     | New Behavior C   | SR-RFC-C111 |
>> | ...   | ...              |             |
>> |       |                  |             |
>> And then we have IS-IS restrictions on where those are advertised.
>> ** IS-IS "legal values" registry **
>> | Name/Description | [End] | [End.X] | [LAN End.X] | Reference    |
>> | Behavior A       | Y     | N       | N           | LSR-RFC-A222 |
>> | Behavior B       | N     | Y       | Y           | LSR-RFC-B222 |
>> | Behavior C       | Y     | N       | N           | LSR-RFC-C222 |
>> | ...              |       |         |             |              |
>> Name/Description or Value whatever you want in column 1 as long as it is 
>> always going to be unambiguous.
>> If you're saying this is not useful, do you perhaps also think our current 
>> "where to advertise" columns in our sub-TLV registries are useless?
> 
> I'm not saying above is not useful, otherwise it would not be in the draft in 
> a first place. What I'm saying is that we do not need a registry for it, it's 
> sufficient to have a table we have, I believe.

Do you think we should get rid of the "used in" columns in the IS-IS TLV and 
sub-TLV registries? The documents that define those TLVs and sub-TLVs already 
indicate which PDUs and TLVs they go in, so why do we need that info in the 
registry?

Thanks,
Chris.
[as WG member]

> 
> thanks,
> Peter
> 
>>>  If you want to find the numerical value(s) associated with that name then 
>>> you refer to the registry created by 
>>> draft-ietf-spring-srv6-network-programming.
>> Yes, but again, I wasn't talking about this.
>> Thanks,
>> Chris.
>> [as WG member]
>>>      Les
>>>    
>>>> -----Original Message-----
>>>> From: Lsr <[email protected]> On Behalf Of Christian Hopps
>>>> Sent: Tuesday, March 10, 2020 4:51 AM
>>>> To: Peter Psenak (ppsenak) <[email protected]>
>>>> Cc: [email protected]; Christian Hopps <[email protected]>; Acee Lindem (acee)
>>>> <[email protected]>; [email protected]; Peter 
>>>> Psenak
>>>> <[email protected]>
>>>> Subject: Re: [Lsr] "Legal" endpoint behaviors [draft-ietf-lsr-isis-srv6-
>>>> extensions-06.txt]
>>>> 
>>>> 
>>>> Peter Psenak <[email protected]> writes:
>>>> 
>>>>> Hi Acee,
>>>>> 
>>>>> On 09/03/2020 14:49, Acee Lindem (acee) wrote:
>>>>>> Hi Peter, Chris,
>>>>>> 
>>>>>> I agree that a number of IS-IS IANA registries have this level of
>>>> specification. For example:
>>>>>> 
>>>>>> https://www.iana.org/assignments/isis-tlv-codepoints/isis-tlv-
>>>> codepoints.xhtml#isis-tlv-codepoints-22-23-25-141-222-223
>>>>> 
>>>>> above is an ISIS specific registry and all external documents just updates
>>>> this
>>>>> protocol specific registry - e.g. the same link attribute defined in some
>>>>> external document has different value in ISIS, OSPF, OSPFv3, etc.
>>>>> 
>>>>> SRv6 SID behaviors are different, because they are not ISIS (protocol)
>>>> specific
>>>>> values - they apply to other protocols (OSPF, BGP-LS, ...). As such a 
>>>>> protocol
>>>>> independent registry defines them and each protocol just refers to it.
>>>> 
>>>> The equivalent to these IS-IS sub-TLV registries would be to add "carried 
>>>> in
>>>> IS-IS sub-TLV/OSPF-Sub-TLV/etc" columns to the SRv6 protocol-agnostic
>>>> behavior registry. This does not seem the correct path to me as now you
>>>> have various transport protocols adding columns to the protocol agnostic
>>>> registry. Instead, I'm suggesting that we create protocol specific 
>>>> registries
>>>> along-side the behavior value registry to document the protocol specific 
>>>> use,
>>>> leaving a reference to these protocol registries in the behavior registry 
>>>> to link
>>>> them.
>>>> 
>>>> Registries are non-normative, and you're not usurping or duplicating the 
>>>> role
>>>> of the SRv6 behavior value registry by tracking additional protocol 
>>>> specific
>>>> restrictions elsewhere by using one. Registries are there to help us keep
>>>> track of stuff. In all the above cases (what goes where) it also helps make
>>>> sure people *have* normatively documented *somewhere* all the cases
>>>> they need to when adding new values/tvls.
>>>> 
>>>> Do you think its better to modify the SRv6 registry directly and add 
>>>> protocol
>>>> specific columns to it?
>>>> 
>>>> Thanks,
>>>> Chris.
>>>> (as WG member)
>>>> 
>>>>> 
>>>>> thanks,
>>>>> Peter
>>>>> 
>>>>>> 
>>>>>> Thanks,
>>>>>> Acee
>>>>>> 
>>>>>> On 3/9/20, 8:28 AM, "Lsr on behalf of Christian Hopps" <lsr-
>>>> [email protected] on behalf of [email protected]> wrote:
>>>>>> 
>>>>>>                > On Mar 9, 2020, at 6:36 AM, Peter Psenak
>>>>>> <[email protected]> wrote:
>>>>>>      >
>>>>>>      > Hi Chris,
>>>>>>      >
>>>>>>      > On 07/03/2020 15:46, Christian Hopps wrote:
>>>>>>      >> 1) I think we should have an IANA registry instead of just a 
>>>>>> table
>>>> defined in section 10 of draft-ietf-lsr-isis-srv6-extensions-06.
>>>>>>      >> The registry could be cross-referenced by and to "SRv6 Endpoint
>>>> Behaviors" for each protocol carrying these behaviors (IS-IS, OSPFv3, ...).
>>>> If/when new behaviors are added they could then update where they are
>>>> supposed to be advertised in the underlying protocols.
>>>>>>      >
>>>>>>      > why do we need a protocol specific registry to advertise values 
>>>>>> that
>>>> are defined in another protocol independent registry? I have never seen
>>>> such a duplication. Looks completely redundant to me.
>>>>>>           You are creating some new sub TLVs (End, End.X, LAN End.X), and
>>>> you
>>>>>> are restricting and directing which externally defined behaviors (values)
>>>> can
>>>>>> be advertised in which of these TLVs. The registry would keep track of 
>>>>>> this
>>>>>> (e.g., "Valid behaviors for sub-TLVs End, End.X, LAN End.X")
>>>>>>           What happens when new behaviors are defined (externally), which
>>>> TLVs
>>>>>> are they supposed to be advertised in? Either the document that defines
>>>> the
>>>>>> new behavior or a related LSR document will have to indicate where this
>>>> new
>>>>>> behavior should be advertised too. That new document would update
>>>> this
>>>>>> registry to track that. Keeping track of this stuff is what registries 
>>>>>> are
>>>>>> for.
>>>>>>           Your table literally looks like a template for the initial 
>>>>>> content
>>>>>> of a registry. :)
>>>>>>           Later in your IANA section you are updating other registries 
>>>>>> that
>>>>>> bear a striking resemblance to this (e.g., what sub-TLV types are valid 
>>>>>> to
>>>>>> advertise in what TLVs).
>>>>>>           >> 2) It's odd that we are referring to the section as "Legal
>>>>>> Behaviors" in the TLV definitions, and then in the actual section using
>>>> "MAY"
>>>>>> terms and no "MUST"/"MUST NOT", but then using "Yes" and "No" in the
>>>> table.
>>>>>>      >
>>>>>>      > a) Legal Behavior - refers to the set of values defined in the 
>>>>>> [I-D.ietf-
>>>> spring-srv6-network-programming] which can be advertised in a particular
>>>> TLV
>>>>>>      >
>>>>>>      > b) We can not use MUST in section 10, as all these TLVs are 
>>>>>> optional
>>>>>>           What's wrong with "If this behavior is advertised it MUST only 
>>>>>> be
>>>>>> advertised in the TLV[s] as indicated by "Y" in the table below, and MUST
>>>> NOT
>>>>>> be advertised in the TLV[s] as indicated by "N" in the table below." or
>>>>>> something like that.
>>>>>>           Thanks,
>>>>>>      Chris.
>>>>>>      (as WG member)
>>>>>>                > c) Yes/No means whether the particular behavior is 
>>>>>> allowed in
>>>>>> the particular END-SID TLV.
>>>>>>      >
>>>>>>      >> Are these suggestions or are they documenting the required
>>>> behavior?
>>>>>>      >
>>>>>>      > these are limitations as to which behavior is allowed to be 
>>>>>> advertised
>>>> in which TLV.
>>>>>>      > thanks,
>>>>>>      > Peter
>>>>>>      >
>>>>>>      >> Thanks,
>>>>>>      >> Chris.
>>>>>>      >
>>>>>>      > _______________________________________________
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>>>>>>      > [email protected]
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>>>>>>      >
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>>>>>> 
>>>>>> 
>>>>>> 
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