Subject: ifLinkUpDownTrapEnable for Phys Layer

From: David Fowler <[email-masked]>
Date: Wed, 18 Feb 1998 09:04:30 -0400

Hi,
I'm just going through the final comments before submitting the final
draft when I noticed a comment from Roy about changing the
recommendation for ifLinkUpDownTrapEnable.

draft 2 says that the trap enable is to be defaulted to enabled for
frameRelayService interfaces.  It also says that is it recommended that
physical interfaces below FRS interfaces be defaulted to disabled  (this
would include ds0Bundles, ds0s, ds1s, data ports) since both are not
required.  This is the opposite recomendation from ifMIB.  The reasoning
for FRS interface traps is that PVC traps are required to be squahed
when they result from an underlying FRS port failure.  The reason for no
DSx traps is that they are redundant.  (i.e. phys layer failures always
result in FRS layer failures)

Roy's suggestion, from the FRF, is that the recommendation be changed to
enabled for physical interfaces.   I am just looking for a little
reasoning behind this (it sounds fine for DS1s).  I guess I don't think
it is useful to generate traps on ds0Bundles and ds0s by default.  Also,
a manager can always enable any interface traps required.

Comments?

David
--
-------------------------------
"One should always be in love.  That is why one should never marry."
-   Oscar Wilde

David Fowler
Newbridge Networks
613-591-3600

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From: "Andrew G. Malis" <[email-masked]>
Date: Fri, 20 Feb 1998 10:13:49 -0500 (EST)

Dave,

> a manager can always enable any interface traps required.

That's consistent with RFC 2233 - the "lowest" layer gets the trap
enabled by default, and the layers above that have it turned off.

Actually, having thought about this for all of a minute of so after
reading your message and checking out the recommendation in 2233, there
are instances when the FR service can go down even though the physical
interface is up (LMI failure, etc.).  So, my own druthers would be to
have it on for the lowest physical layer (the DS1 of a DS0 or DS0
bundle, for example), plus the FR service layer, but off otherwise.
However, abiding by 2233 is probably for the best.

Cheers,
Andy
________________________________________________________________________
Andrew G. Malis  [email-masked]  phone:978 952-7414   fax:978 392-1484
Ascend Communications, Inc.        1 Robbins Road     Westford, MA 01886

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From: David Fowler <[email-masked]>
Date: Mon, 23 Feb 1998 08:36:21 -0400

Andy,

After I sent my note, I thought of the LMI case where FR can be down where
DS1 is not.  I am leaning towards recommending that DS1s get enabled.

I think we do need to keep FRS enabled by default as well.  I've been trying
to recreate in my mind why we made this decision X months ago, andthe only
thing I can come up with was that the PVC traps are describes as "This trap
indicates that the indicated PVC has changed state.  This trap is not sent if
an FR_UNI changes state, a linkDown or linkUp trap should be sent
instead."    This text tells me to send a trap for the FRS entry, so we
really should have it on be default.  My implementation experience tells me
this is useful as well.

So, I will change the word disabled to enabled for DS1 traps and clarify that
ds0 and ds0 bundle traps should remain disabled.

Regards,
David

--
David Fowler
Newbridge Networks
613-591-3600

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From: "Andrew G. Malis" <[email-masked]>
Date: Tue, 24 Feb 1998 14:34:17 -0500

Dave,

>ds0 and ds0 bundle traps should remain disabled.

Sounds good!

Cheers,
Andy