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20050217: packet shaping and IDD at Kean.edu

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  • Subject: 20050217: packet shaping and IDD at Kean.edu
  • Date: Thu, 17 Feb 2005 14:38:00 -0700
Shing Yoh,

In order for us to help you, would you please answer the following
questions:

    1.  What do you mean by "800kps". Is that in kiloBITs-per-second
        or kiloBYTES-per-second?

    2.  What is the bandwidth of the external connection to your
        university?  OC-1?  OC-2?  OC-3?

Regards,
Steve Emmerson

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------- Original Message

>To: address@hidden
>cc: address@hidden
>From: Shing Yoh <address@hidden>
>Subject: Need help to resolve long latency issue on IDD/LDM
>Organization: UCAR/Unidata
>Keywords: 200502172036.j1HKaUv2005158

To : Unidata Support

Since a few months ago when packet shaper software was installed on our 
campus network, we encountered serious issue on ingesting model data 
(missing data and high latency).  From the information that I can gather 
so far from the Unidata web pages and email archive, I had talked to the 
IT people on the campus and had already taken the following steps :

(1) I have changed the product queue size in ldmadmin $pq_size=1000000000 
and restart the ldm.  The file size of ldm.pq is running at 1015898112 
byte.

(2) I have talked to the IT people and I was told that we are currently 
set at 800kps for bandwidth to our server "hurri.kean.edu".  The setting 
is for the all ports and traffic to our server since the software can not 
be set for just ldm IP port 388.

(3) The above rule for traffic to our server has priority 10, the highest.

Unfortunately, with all these changes, our latency for HDS model data
is still at 4000s (with a much reduced set of model data then what we used 
to ingest).

I am running out of ideas to try or suggestions to IT people.  Are there 
any suggestions from Unidata that I or our IT people should try or 
investigate in order to resolve this long latency issue ?

By the way, the packet shaper software that they are using is the 
NetEnforcer by Allot Communications, Version 5.1.   Any help will be 
appreciated.

Dr. Shing Yoh 
Dept. Geology & Meteorology            K     K EEEEEEE    A    N     N
Kean University                        K    K  E         A A   NN    N
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------- End of Original Message