Thank you

Sean Doran smd at
Mon Feb 6 17:13:21 UTC 1995

Actually, what happened in this case was a typo in a filter
list on icm-dc-1 which blocked the announcement from the Dante

One or more of us here is at fault for accidentally
adjusting things in the wrong way.  Chalk up another round
to fat finger syndrome...  Some automation for updating some
of AS 1800's configuration is in the works, so hopefully
this won't be a recurring problem after that's done.

We did have some difficulty in tracking this down initially,
as we had no idea who should have been announcing AS 3058
routes to AS 1800, and the filter-list appeared good at
first glance.

Dante looked into things on their end over the past couple
of days, and informed us that they were announcing things to us
OK and that things looked OK on the Dante 4000 in D.C., and asked
us to re-check the filter list.

Sure enough, they were right, and the 120 line filter-list 
had a botch near the end.

This was fixed this morning (D.C. time) and routing in this
case seems to be working OK.

A note went out to the people directly involved earlier

- --
Sean Doran <smd at> / <smd at>

- --
| From sgoldste at Mon Feb  6 11:51:29 1995
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| Content-Type: text/plain; charset="us-ascii"
| Date: Mon, 6 Feb 1995 11:49:46 -0500
| To: "Vasenin Valery A" <vasenin at>
| From: sgoldste at (Steve Goldstein)
| Subject: Re: Thank you
| Cc: Sean Doran <smd at>, avg at (Vadim Antonov),
|         nwg at
| Status: RO
| At 7:36 PM 2/06/95, Vasenin Valery A wrote:
| >                                Dear Steven!
| >
| >        I'm deeply grateful to you for the timely solution about the
| >announcement MSUNet in NSF.
| >
| >                                        Sincerely yours Valery Vasenin.
| Dear Valery,
| Actually I had not done ANYTHING...yet.  I read your first message earlier
| this morning, and had not yet had the opportunity to look into the exact
| nature of the problem, and then I get this new message from you.  So,
| please let me try to explain a few things that might shed light on the
| problems of MSU's inablilty to communicate with portions of the NSFNET
| community from time to time.
| Two things are happening that are probably related to the problems you have
| been experiencing:
|         1. The NSFNET is being decomissioned (abandoned, going away), and it
|            is being replaced with several interconnected national Internet
|            service providers: MCInet, SprintLink, and ANSnet.  The transition
|            is taking place now and will last fur a few months, and things are
|            not always stable during the transition.  Route that work one hour
|            may be replaced with routs that do not always work in the next hour,
|            and these have to be identified and corrected.
|         2. The routers on the East Coast  of the United States, mainly around
|            Washington, D.C., are "glowing red hot" with traffic overloads.  Some
|            new code has been written to improve their performance, and network
|            experts try to install the new code and observe its performance at
|            low traffic times here (around our midnignt), which correspond to
|            periods of high activity in Russia with the 8-hour time difference.
|            One by-product of all the attempts to upgrade the code is "route
|            flapping" instability,in which the connectivity and routing
|            information contained in the routing tables cannot keep up with the
|            changing physical realities of the network itself: there is just too
|            much work for the routers to do, and they cannot keep up with both
|            packet switching and routing table updating.
| So, if your problems corrected themselves without my intervention at all,
| my guess is that one or both of the above mechanisms must be the culprits.
| If you continue to experience intermittent problems, please have your
| technical people write to Sean Doran <smd at> and/or Vadim Antonov
| <avg at>  at Sprint with the precise description of the
| problems as you see them.
| There is no policy reason of which I am aware that would cause the problems
| that you have experienced.  We have been routing traffic from Russia for at
| least a year, and I recall having seen that a new MSU network has just been
| added to the data base. MAYBE what you have observed is that the addition
| of the newly registered MSU network entry has just taken effect.  Below, i
| will copy a notice about the [proposed] new procedures to replace the
| current NSFNT procedures for registering routing information.
| Best wishes,
| Steve

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