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20040113: LDM Buffering Question

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  • Subject: 20040113: LDM Buffering Question
  • Date: Tue, 13 Jan 2004 14:00:28 -0700
Chris,

>Date: Tue, 13 Jan 2004 14:42:16 -0600
>From: "Chris D Gilbert" <address@hidden>
>Organization: US DoC/NOAA/NWS/NEXRAD OSF
>To: Steve Emmerson <address@hidden>
>Subject: Re: 20040113: LDM Buffering Question

The above message contained the following:

> Great information! That is what I needed...

Glad I could help.

> Yes, we (ROC Engineering) have put the LDM software into our RPG build
> 5.0 baseline. We have 6 month build cycles. So, please contact me with
> any LDM changes that may need to be implemented in a future build...

OK.

The main thing is to ensure that the pqing_bdds(1) utility is run by an
EXEC entry in the LDM configuration-file (etc/ldmd.conf) so that its
SIGCONT signals are delivered to the upstream LDM process (but you know
about that).

We did think that a radar data-product should consist of one entire scan
(i.e., 360 radials) rather than three separate pieces -- but there didn't
seem to be much interest in the NWS for doing this.

> > I believe the radar-to-regional HQ bandwidth is 128 kbps, if I'm not
> >   mistaken.
> 
> It is actually WFO-to-regional HQ.  In the case of NWS sites the
> RPG/BDDS hardware is in the WFO. In the case of DOD sites the RPG/BDDS
> hardware is in a remote shelter (like on a mountain top). For DOD
> sites, we have to get this data to the WFO before we can put it on
> NWSnet. That is why bandwidth is a higher concern for us at DOD
> sites...

Interesting.  Thanks for the info.

> Thanks again!

You're most welcome.

Regards,
Steve Emmerson
LDM Developer