Re: [Isis-wg] WG Last Call for draft-ietf-isis-auto-conf-04

Acee -

Thanx for reviewing the document.
Responses inline.

> -----Original Message-----
> From: Isis-wg [mailto:isis-wg-bounces@ietf.org] On Behalf Of Acee Lindem
> (acee)
> Sent: Sunday, January 22, 2017 5:39 AM
> To: Christian Hopps; isis-wg@ietf.org
> Cc: draft-ietf-isis-auto-conf@ietf.org; isis-chairs@ietf.org; isis-ads@ietf.org
> Subject: Re: [Isis-wg] WG Last Call for draft-ietf-isis-auto-conf-04
> 
> Hi IS-IS WG,
> 
> I have reviewed the document and support publication. I have the following
> minor comments:
> 
>     1. It should be made clear that the A-Bit indicates that an IS-IS router
> supports auto-configuration and, is not, necessarily auto-configured itself.
> After reading the whole draft, I know that this is the definition of the bit but
> the initial text says the router is ³operating in auto-configuration mode.²

[Les:] It is clearly stated that the A flag does indeed mean 

" the router is operating in auto-configuration mode."

I do not see any text which suggests otherwise.

???

>     2. In the duplicate detection in section 3.4.3, could you note that an IS-IS
> router should be able to detect discern the case where two interfaces on the
> IS-IS router performing auto-configuration are connected to the same
> network.
> 
[Les:] Multiple connections of the same system to the same network can occur in the absence of auto-configuration and detection of this case is not altered by auto-configuration. This is detected by receiving a hello with the same source MAC address as a local interface. There are then the following cases:

1)Two interfaces on the local router are connected to the same media. This is further validated by having the same systemID. The means for detecting this as well as resolving this are not altered by auto-configuration.

2)Two neighbors connected to the same network have the same source MAC address. This is distinguished by having different system IDs in the hellos. The means for detecting this as well as resolving this are not altered by auto-configuration.

3)Two neighbors connected to the same network have the same source MAC address and the same systemID. This is distinguished by having different router fingerprint TLVs in the hellos - something only an auto-config router could do. But the additional detection capability does not provide any additional means to correct this issue.

The authors discussed this point during the writing of the draft and decided specifically NOT to comment on this issue as it by nature is no different than what can occur without auto-config and there is no good way to automatically recover from this case i.e. clearly we cannot alter the physical connections by programmatic means - nor do we assume/require a programmatic capability of assigning MAC addresses.

So, I am not sure what we could say other than to note that this can occur - but non-auto-config implementations already have to detect this - so does it make sense to comment on this in the auto-config draft?

   Les

> Thanks,
> Acee
> 
> On 1/17/17, 7:00 AM, "Isis-wg on behalf of Christian Hopps"
> <isis-wg-bounces@ietf.org on behalf of chopps@chopps.org> wrote:
> 
> >
> >Hi Folks,
> >
> >We are starting a WG Last Call for
> >
> >  "ISIS Auto-Configuration"
> >  - https://datatracker.ietf.org/doc/draft-ietf-isis-auto-conf/
> >
> >The WGLC will expire in 2 weeks on Jan 31, 2017.
> >
> >Thanks,
> >Chris & Hannes.
> 
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