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[LDM #GUQ-669331]: Both Radar and Satellite feeds stopped downloading abruptly

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  • Subject: [LDM #GUQ-669331]: Both Radar and Satellite feeds stopped downloading abruptly
  • Date: Wed, 04 Sep 2019 11:12:24 -0600
John,

> *   What is the “LATENCY (SECONDS)” really mean?  It's clearly not 3,000+ 
> seconds.

Yes, it is. But the "latency" here isn't network latency; instead, it's LDM 
*product-latency*, which is the time from when the product was created by the 
source to when it was finally received by the destination. If this latency is 
greater than the maximum latency parameter in the LDM registry, then the LDM 
won't insert the product into its product-queue.

> *   Also, how is that latency on your server calculated?  Is it done by time 
> since last packet, the iRTT field within the initial handshake, or by some 
> other method?

Ibid.

> I’m still seeing no huge difference between the captures

Captures? Do you mean wireshark(1) or tcpdump(1) output?

> during fast/normal times and bad/slow/latent times in terms of time since 
> last packet (fast times are .0175 seconds and right now is .03 seconds).  
> Really would love to have a capture of our communications from your server to 
> ours for comparison.   3 seconds would be plenty.

I'll see what can be done.

Regards,
Steve Emmerson

Ticket Details
===================
Ticket ID: GUQ-669331
Department: Support LDM
Priority: Normal
Status: Closed
===================
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