wiki:liss2ew_scnl

Version 2 (modified by branden, 9 years ago) (diff)

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Earthworm Module: liss2ew_scnl

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Function

Liss2ew_scnl is the earthworm module for receiving trace data from the Live Internet Seismic Server. This is a rewrite of liss2ew for SCNL and has only been tested under windows (new in EWv7.0)

Details

Liss2ew_scnl is the earthworm module for receiving trace data from the Live Internet Seismic Server. This module was rewritten from the liss2ew by Peter Lombard and converted to C++ when the SCNL modifications were made. This version was contributed by the NEIC HYDRA group and has only been compiled and tested using Windows OS.

The LISS is a very simple service that provides trace data in miniSEED format in near-real-time over the Internet. The liss2ew module will connect to one LISS, read selected streams of trace data, and write that trace data into the earthworm transport ring.

One LISS normally has data for a single station. One or more components are sent together in the data stream. In some cases, one component is provided in more than one sample-rate. The `location code' is used in this case to label the different kinds of data.

The miniSEED format may contain a few other types of blockettes besides the Data-Only blockette. (You can read the PDF version of the SEED manual if you want to know more.) Currently liss2ew ignores these non-trace-data blockettes.

Besides the ASL, there are several other LISS servers. Some digital seismographs produce miniSEED. There is be an earthworm LISS server module, ew2liss. The ew2liss is NOT SCNL compatible yet. This will allow the exchange of earthworm trace data by an alternate format to the current Import-Export import/export] combination.

Example Configuration File

The commands for liss2ew_scnl are very different from the old liss2ew. Here is an example configuration file:
#
#
#                     Configuration File for liss2ew_scnl
#

MyModId          MOD_LISS2EW
OutRing          WAVE_RING       # Transport ring to write output to,
                                 # InRing and OutRing may be the same.
HeartBeatInterval     30         # Heartbeat interval, in seconds,
LogFile            1             # 1 -> Keep log, 0 -> no log file
                                 # 2 -> write to module log but not stderr/stdout
#Debug                           # Write out debug messages (optional)


lenSEED      512                 # The size of SEED records to read from LISS
                                 # OPTIONAL; defaults to 512 bytes.

SocketTimeout  30                # Socket timeout in seconds; not more than
                                 # HeartBeatInterval

TraceLength    100               # Number of trace data samples to put in one
                                 # TRACE_BUF packet. Range is 10 - 1000

# List each Internet source in an "Address" command, followed by the IP number (or
# DNS name) and port number.
# Following each Address command, list one or more sta/comp/net/location expected from
# that source in an "SCNL" command, followed by the station, component, network and
# location codes.  Location code (LC) is a 2-digit code to further
# identify a seismological data path. LC (and ONLY LC) may be given as `*' to
# specify a wildcard. If the LISS has more than one LC for a give SCN,
# using the wildcard will generate errors in the log file.
# If liss2ew sees an SCNL which is not listed here, it will be ignored.

Address     136.177.24.74    4168
SCNL  WMOK BHZ  US  00 
SCNL  WMOK BHN  US  00  
SCNL  WMOK BHE  US  00 
SCNL  WMOK LHZ  US  00 
SCNL  WMOK LHN  US  00 
SCNL  WMOK LHE  US  00 

Address 136.177.24.74    4166
SCNL  AFI  BHE  IU  00
SCNL  AFI  BHN  IU  00
SCNL  AFI  BHZ  IU  00
SCNL  AFI  LHE  IU  00
SCNL  AFI  LHN  IU  00
SCNL  AFI  LHZ  IU  00

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