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RE: IF types durring review of EPON-04
Ok, I've looked through EPON-04 with respect to the relationship to the
interfaces MIB and the Ethernet mib. (I also saw lots of typos and
grammatical errors in EPON-04, so someone should probably go through it
for those. It also has lots of acronyms which are not expanded on first
use.)
The key sentence in EPON-04 is in section 3.1:
> Implementing this module therefore MUST require implementation of
> Interfaces MIB module [RFC2863] and Ethernet-like Interfaces MIB
> module [RFC3635].
This is fine, since throughout the doc it says that EPON interfaces are
Ethernet-like interfaces and they don't want to duplicate all the
objects in that MIB.
However, the problem is it uses gigabitEthernet(117).
Section 3.2.4 of RFC 3635 (which, as quoted above, is a MUST for EPON
interfaces) says:
> It is REQUIRED that all ethernet-like interfaces
> use an ifType of ethernetCsmacd(6) regardless of the speed that the
> interface is running or the link-layer encapsulation in use.
and
> A requirement for
> compliance with this document is that all ethernet-like interfaces
> MUST return ethernetCsmacd(6) for ifType, and MUST NOT return
> fastEther(62), fastEtherFX(69), or gigabitEthernet(117).
It's pretty clear from the above that the only legal value for use in
EPON is ethernetCsmacd(6).
Similarly, the ianaiftype-mib says:
> gigabitEthernet (117), -- Obsoleted via
RFC-draft-ietf-hubmib-etherif-mib-v3 ethernetCsmacd (6) should be used
instead
(Yes the reference in the comment is stale... per
http://www.ietf.org/internet-drafts/draft-ietf-hubmib-etherif-mib-v3-03.
txt it is the same as RFC 3635 quoted above.)
The layering model described on page 13 (of using one Ethernet-like
interface that is stacked on top of a set of other Ethernet-like
interaces) is fine. This is equivalent to what RFC 3371 (the L2TP MIB)
does for multilink PPP for similar reasons.
Since EPON is not defining a new ifType, the other requirements in RFC
2863 don't apply to it as they are met by RFC 3635.
-Dave
> -----Original Message-----
> From: owner-mreview@ops.ietf.org [mailto:owner-mreview@ops.ietf.org]
On
> Behalf Of Dave Thaler
> Sent: Friday, May 12, 2006 10:49 AM
> To: David T. Perkins; mreview@ops.ietf.org
> Subject: RE: IF types durring review of EPON-04
>
> I've been doing the reviews of relationships to the Interfaces MIB, so
> I can do this, but I'm swamped right now. I could probably get to
this
> by end of next week (5/19) if someone else doesn't get to it before
> then.
>
> -Dave
>
> -----Original Message-----
> From: owner-mreview@ops.ietf.org [mailto:owner-mreview@ops.ietf.org]
On
> Behalf Of David T. Perkins
> Sent: Friday, May 12, 2006 10:25 AM
> To: mreview@ops.ietf.org
> Subject: IF types durring review of EPON-04
>
> HI,
>
> I'm doing a second review of EPON-04 I-D, which is
>
http://www.ietf.org/internet-drafts/draft-ietf-hubmib-efm-epon-mib-04.tx
> t
>
> It is very complex and the previous review raised many questions.
> The good news is that it is MUCH better, and it is finally to the
> level that someone can make sense of it. However, given that
> it is an interface MIB module, there are many additional
> considerations that must be followed. I don't remember all of
> them, and would need to refresh myself with these considerations
> to do a complete job. Is there anyone that can do a scan
> after I finish the first pass?
>
> One question that I have so far is what interface type
> to use for the virtual links. The document uses the
> same value as the physical (which is gigabitEthernet(117)),
> but it seems to me that the propVirtual(53) is more
> appropriate.
>
> In trying to determine the value for ifType, I looked at
> http://www.iana.org/assignments/ianaiftype-mib
> In it I see that there are 234 types defined.
> This seems like an extremely large number. Also,
> there is not a reference for each assigned value.
> Thus, I could not figure out from looking at
> these values what values the should be used
> in the EPON MIB module. This seems like a generic
> problem that anyone implementing object ifType
> would encounter. And a delemma for anyone creating
> a new interface MIB module.
>
> Are there any suggestions that would help me
> now with the EPON MIB module, and for making it
> easier for future interface MIB module developers?
>
> Regards,
> /david t. perkins
>
>
>
>