Real-time, self-managing data flows -- Unidata will foster
and support the existence of real-time data flows that encompass a
broad range of Earth-system phenomena, can be accessed with ease by all
constituents, and are self managing in respect to changing contents and
--A goal of Unidata 2008: Shaping the Future of Data Use in the
LDM-6 Status Report
The LDM has been stable since the last report.
At the request of the NWS, Steve Emmerson is traveling to
national and regional NWS Headquarters in order to conduct
training sessions on the LDM system and to vet (i.e., "tune
up") their existing LDM networks. This is being done in
preparation for the establishment by the NWS of a nationwide
distribution system for NEXRAD level II data using the Internet
and the LDM. The NWS is paying all relevant travel, salary,
and benefits. So far, Steve has visited the National NWS HQ in
Silver Spring, MD, and the Western Region NWS HQ in Salt Lake
IDD Status Report
166 machines at 100 sites are running LDM-6 and
reporting real time statistics. Sites continuing to run
LDM-5 are being encouraged to upgrade to LDM-6 as quickly as
possible. Unidata staff have remotely installed LDM-6 at many sites
to expedite the changeover process.
Real time LDM statistics can be found in the Real
Time IDD Statistics webpage. The topology and data flow information
reflects changes in feed requests within a few minutes of changes. Rtstats
have proven to be most useful in diagnosing reception problems
at sites, especially when universities have implemented restrictions
on packets volume in and out of the campus without regard for
their user needs.
In order to correctly guage real-time status of the IDD, it is
important for all sites participating to accurately maintain their
clocks (easily done through Network Time Protocol software and servers).
NWS will use LDM-6 to move NEXRAD Level II data. LDM-6.0.14 will be
in the initial distributed build.
Unidata has obtained and tested a DVB-S receiver to prepare for the NWS migration
from the current operational broadcast of NOAAPORT data streams to a DVB-S based
system. Tests have shown compatibility between the Unidata developed software
used to ingest the NOAAPORT data feeds and the DVB-S broadcast stream
implemented by the NWS for evaluation.