Joel,

On Aug 14, 2013, at 5:57 AM, Joel M. Halpern <[email protected]> wrote:

> The virtual router question is an interesting one.  I believe that the answer 
> is "it depends".
> On the one hand there is a base device.  There may or may not need to be 
> capability for I2RS access to that entity.

It seems to me that this is dependent on whether the device is part of the 
routing system -- not whether it is physical or virtual. Does it have a RIB, 
participates in routing, and an interface to routing? If the answer is yes, 
then I2RS needs access (whether the base device or an individual virtual one).

> Then there are the individual virtual routers.  My inclination would be to 
> use separate I2RS clients, each with a separate I2RS identity and identifier.

I agree with this (assuming you meant to write "I2RS agent" or "I2RS server" 
instead of "I2RS client") -- basically, if it is a node in the topology, it 
needs its I2RS identity.

>  But there appears to be enough flexibility in the modeling that we are 
> discussing that one could probably model it as one I2RS agent with various 
> pieces and parts.  In which case that one agent has only one identity and one 
> identifier.
> 

I think there's potentially more than this, namely: proposed I2RS topology 
information models support node aggregation / virtual topologies. Shouldn't 
each node at a different level of the hierarchy have its own identity (and 
identifier)?

Thanks,

-- Carlos.


> Yours,
> Joel
> 
> On 8/14/13 5:24 AM, t.petch wrote:
>> ----- Original Message -----
>> From: "Alia Atlas" <[email protected]>
>> To: "Joe Marcus Clarke" <[email protected]>
>> Cc: <[email protected]>
>> Sent: Tuesday, August 13, 2013 9:01 PM
>> 
>> 
>>> Hi Joe,
>>> 
>>> Thanks for the detailed review and suggestions.  Responses are
>> in-line.
>>> 
>>> Alia
>>> 
>>> On Wed, Jul 31, 2013 at 6:57 AM, Joe Marcus Clarke
>> <[email protected]>wrote:
>>> 
>> <snip>
>>>> Section 6.4:
>>>> 
>>>> Each I2RS Client will have an identity; it can also have secondary
>>>>    identities to be used for troubleshooting.
>>>> 
>>>> JMC: Each application will have a _unique_ identity.
>>>> 
>>> 
>>> [Alia] Hmm, this ties into the discussion about how we want to handle
>>> redundancy and recovery for clients.   It's also a bit of a
>> tautology - a
>>> client is solely identified by its identity.    I have changed it to
>> say
>>> that "Each I2RS Client will have a unique identity" - but  that just
>> helps
>>> clarify the intent.
>> 
>> I think that this nicely encapsulates a confusion between identity and
>> identifier.  Identifiers identify.  Objects, in a very generic sense,
>> have identity.  Thus if a human being is an instance of an object, they
>> may be identified, based on context, by SSN, passport number, name, name
>> and date of birth, cell phone number etc; all could be valid
>> identifiers: but equally, a cell phone number could be the identifier of
>> a cell phone, which is associated with a function and multiple people,
>> while the cell phone could also be identified by its IMEI so the
>> determination of what is an identity, may take some consideration.  This
>> is often critical in security; you have a secure channel but with what?
>> Is the identifier sufficient proof of the identity?
>> 
>> Working with routers, you usually have multiple identifiers; the SNMP
>> sysName is not (usually) the OSPF 32 bit router id, while the BGP
>> Identifier (note, identifier) is different again.
>> 
>> Identifiers exist within a namespace, with rules about syntax,
>> uniqueness and so on (even if this are not made explicit).
>> 
>> The revised I-D contains
>> " A secondary  identity is merely a unique, opaque identifier ..."
>> and
>> "An I2RS Client may supply a secondary opaque  identity .."
>> 
>> I think that most uses of the word "identity" in this I-D are actually
>> referring to "identifier" but at the same time, given that almost all
>> routers have multiple identifiers (as above), then this issue, of the
>> difference between identity and identifier needs making explicit in this
>> I-D.
>> 
>> Tom Petch
>> 
>> (p.s. if you have multiple virtual routers in one physical router, how
>> many identities are there? Discuss.)
>> 
>> 
>> _______________________________________________
>> i2rs mailing list
>> [email protected]
>> https://www.ietf.org/mailman/listinfo/i2rs
>> 
> _______________________________________________
> i2rs mailing list
> [email protected]
> https://www.ietf.org/mailman/listinfo/i2rs

Attachment: signature.asc
Description: Message signed with OpenPGP using GPGMail

_______________________________________________
i2rs mailing list
[email protected]
https://www.ietf.org/mailman/listinfo/i2rs

Reply via email to