Subject: [IGSMAIL-1318] IGS Data Flow Improvement
From: Werner Gurtner, Jim F. Zumberge
Date: Tue, 14 May 1996 23:26:53 PDT

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IGS Electronic Mail      Tue May 14 23:26:53 PDT 1996      Message Number 1318
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Author: Werner Gurtner, Jim F. Zumberge
Subject: IGS Data Flow Improvement

Rapid Orbits: Improvement of the IGS Data Flow
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At the last Analysis Center Workshop in March 1996, strong arguments for
a faster turnaround time for the generation of the IGS Rapid Orbits (24
hours for the combined Rapid Orbits) were presented.  To achieve this will
require an improvement in the data flow, both in latency and in reliability.

Given the limits of the Internet, especially during the (European) day
times within Europe and on transatlantic lines, a concentration of the
data transmissions in the very first hours after midnight UT is suggested.

The requirements can be met if the daily data -- at least of those stations
used for rapid orbit generation -- are available AT THE ANALYSIS CENTERS before
06:00 UT, and, as a prerequisite, at all Global Data Centers before 05:00 UT!

Many of the sites currently used for Rapid Orbits (and other products, too)
could already now fulfill easily these requirements, although some
modifications in the scheduling of the data handling at the sites and at the
Data Centers involved may be necessary.

Below there is a list of those sites pointed out by two or more Analysis
Centers to be used for rapid orbit generation (. first, .. second priority),
together with the names of the Operational Centers involved and the latency
number (10=within 5 hours, 9=within 15 hours etc) as determined by IGSCB/JPL
during one of the recent weeks. 

The latency number just gives a coarse indication, they are based on data
arrival at the three Global Data Centers.

*  We urgently ask all the Operational Centers / sites involved, as well as
*  the Regional and Global Data Centers, to review their procedures at least
*  for the sites listed below in order to meet above requirements.

!  Please check carefully the degree of automation of your procedures to help
!  avoid the reduced availability of data over the weekends.

Of course a "10" is what will have to result for all "rapid orbit sites".

Please contact Werner Gurtner ([email-masked]), if necessary, for
coordination purposes or details in the data flow and send him in any case
informations about your related actions or concerns.

Thank you for your cooperation.

Jim F. Zumberge
Werner Gurtner

IGS Central Bureau

--------------------------------------------------------------------------
Site         EMR         COD        GFZ   JPL  SIO    Oper/Site    Latency
--------------------------------------------------------------------------
algo          .           .          .      .   .     nrcan           10
ankr                                 ..         .     ifag/wtz         ?
areq                                 .      .   .     jpl              ?
bogt                                 ..     ..  .     jpl              7
cas1                                 ..         .     auslig           ?
drao                                 .          .     pgc             10
fair                      .          .      .   .     jpl              9
fort          ..                     .      .   .     cignet           9
gold          .           .          .      .   .     jpl              9
guam                                 .      .   .     jpl              8
hart          .           .          .      .         cnes             1
irkt                                 .          .     delft            5
kerg                                 .      .   .     cnes             7
kit3          ..                     .      ..  .     gfz              8
kokb          .           .          .      .   .     jpl              9
kosg          .           .          .          .     delft/kosg       3
kour                                 ..     .         esoc            10
lhas                                 .          .     ifag/wtz         0
mac1                                 .          .     auslig           2
madr          .           .          .      .   .     jpl              9
mali                                 .          .     esoc             7
mas1                                 ..     ..  ..    esoc             9
mcm4          .                      .          .     jpl              9
mdo1                                 .      ..        jpl              9
ohig                                 ..         .     ifag/wtz         0
pama                                 .          .     cnes             6
rcm5                                 .      ..  ..    cignet          10
sant          .           .          .      .   .     jpl              9
sey1                                 .          .     jpl              0
tidb          .           .          .      .   .     jpl              9
trom          .           .          .      .   .     sk               5
tskb          .                      .          .     gsi             10
usud                                 .      .   ..    jpl              8
wett          .           .          .          .     ifag/wtz         9
yar1                      .          .      .   .     jpl              8
yell                      .          .          .     nrcan            9
--------------------------------------------------------------------------

[Mailed From: Werner Gurtner <[email-masked]>]