Retrieve Data From a CAPS Server

CAPS provides additional tools to access data and information on a CAPS.

Name Description
capstool A command-line tool for retrieving data and information from a CAPS server.
caps_plugin The plugin fetches miniSEED data from a CAPS server and provides the data to seedlink
caps / capss The RecordStream implementations for CAPS.

RecordStream for SeisComP modules

SeisComP applications access waveform data through the RecordStream interface. To fetch data from a CAPS server the caps or capss RecordStream may be used. Similar to https capss will establish a Secure Socket Layer (SSL) communication.

Configuration

In order to make use of the the caps RecordStream, the rsas plugin must be registered. Add the rsas plugin in the global configuration or to the modules that require the RecordStream, e.g. scautopick, scamp, scolv, scrttv:

plugins = ${plugins},rsas

Optional Parameters

  • arch - read from CAPS archive only.
  • ooo - out of order, data are fetched and provided in the order of their arrival in the CAPS server, useful for analysing if data have arrived out of order.
  • pass - password if server requires authentication
  • request-file - file specifying the streams to be requested. One stream per line. Per line: net sta loc stream startTime endTime.
  • timeout - timeout of acquisition in seconds. Data acquisition will be restarted.
  • user - user name if server requires authentication

The parameters can be combined.

URL Description
caps://server:18002?arch Read data from CAPS archive. Stop data acquisition when all available waveforms are fetched.
caps://server:18002?ooo Fetch data in the original order of arrival.
caps://server:18002?request-file=request.txt Request only streams in time intervals given in request.txt
caps://server:18002?timeout=5 Apply a timeout of 5 seconds.
capss://server:18022?user=foo&pass=bar  

Combination with other RecordStream interfaces

The caps and the capss RecordStream may be combined with other RecordStream interfaces.

Examples:

  1. Decimation

    Use the decimation RecordStream interface to fetch data from a CAPS server running on localhost decimated to 1 sample per second.

    global configration:

    recordstream.service = dec
    recordstream.source = caps/localhost:18002?rate=1
    

    command line parameter:

    -I dec://caps/localhost:18002?rate=1
    
  2. Resample

    Use the resample RecordStream interface to fetch data from a CAPS server running on localhost resampled to 16 samples per second.

    global configration:

    recordstream.service = resample
    recordstream.source = caps/localhost:18002?rate=16
    

    command line parameter:

    -I resample://caps/localhost:18002?rate=16
    

Direct file access

The data files in the CAPS archive contain a small additional header describing the data format. Read the format documentation for more details. In contrast to miniSEED files in SDS archives created e.g. by slarchive or scart, the files in the CAPS archive cannot be directly read by an application.

Use the command-line tool capstool for fetching data from a CAPS server based on time windows. capstool will read the data, strip the header and provide the data in their original format. capstool also provides information on available stations (-L) and streams with their time windows (-Q)

FDSNWS

CAPS speeks natively FDSN Web Services, FDSNWS providing waveform data via dataselect. Information on events and stations are not delivered. Read the documentation of the CAPS server for the configuration.

Winston waveform server (WWS)

CAPS speeks natively Winston Waveoform Server, WWS) protocol, e.g. to Swarm by USGS. Read the documentation of the CAPS server for the configuration.