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[LDM #MIJ-856283]: LDM Data Tags

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  • Subject: [LDM #MIJ-856283]: LDM Data Tags
  • Date: Thu, 13 Oct 2011 13:02:41 -0600
Hi Brad,

re:
> We have an LDM server that provides weather data to various customers.
> 
> I would like to know how we obtain a unique tag to identify the data that
> we provide so that users can filter on our data.

The number of datastream types that the LDM-6 supports is fixed at 31.
Unfortunately, there are no spare feedtypes available, so you will need
adopt a different tactic for making portions of dataflows uniquely
identifiable.

re:
> If we can obtain a unique tag, what is the process?

What you can do is:

- include a field in each Product ID that uniquely identifies
  something meaningful for the end-user to filter on. We suggest
  that this field be the first one in the Product ID to make
  things easier for the end-user(s)

- if your objective is to limit access to one or a small number
  of downstreams, then you can craft your ALLOW(s) to specify
  the unique field that you include in the Product IDs

The approach of specifying a unique field in the Product ID
is being used by lots of folks including private companies
that are providing data to paying customers.  The Antarctic
research community, for instance, uses the concept to segregate
dataflows:

notifyme -vl- -f EXP -h antidd.ucar.edu -o 3600

...
Oct 13 18:53:37 notifyme[19688] INFO:   995215 20111013185026.533     EXP 000  
ANT.AMRC.PseudoComposite.20111013..gif
Oct 13 18:53:37 notifyme[19688] INFO:       84 20111013185002.178     EXP 000  
USAP.NCAR.AMPS.WRF.D3.2011101312.F031.P0200.RWMR.grb
...

Here 'ANT.AMRC' is used to identify products that originate from the AMRC 
program
at the University of Wisconsin at Madison, and 'USAP.NCAR' is used to
identify AMPS (WRF with polar physics) model output from the MMM program
in NCAR.

NB: the periods in the above examples are not needed; they were employed
by the creators of the products because they made sense to them.  I
personally would have used spaces...

re:
> Thank you,

No worries.

Cheers,

Tom
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Ticket Details
===================
Ticket ID: MIJ-856283
Department: Support IDD
Priority: Normal
Status: Closed