SUNWORM uses concepts (and some code) from the EARTHWORM system being developed by the USGS in Menlo Park. Real-time data arriving in the SUNWORM computer from a local A/D S-Bus card and from digital telemetry lines are `broadcast' by data-producer programs into shared memory for use by follow-on data-consumer analysis programs. The data-producers receive no feedback from the data-consumers and there may be from none to many such programs listening for the broadcast data.

A trigger algorithm is one data-consumer program which saves time windows of data for all channels for events of interest. While real-time picking is not curre ntly done on SUNWORM, station trigger times (resolution of one second) are used as crude picks to obtain rough event locations for larger earthquakes. This and integrated signal levels from triggered channels allow preliminary estimates of location and magnitude within one minute of origin time for notification purposes. An additional fairly robust estimate of location and magnitude is available within one minute after event termination.

It has been easy to adapt new data streams to the system and easy to develop new analysis applications such as real-time seismogram displays and real-time seismic amplitude monitors (RSAM) for volcano monitoring.

The PNSN SUNWORM currently records 160 channels of short-period analog telemetry data, one local broad-band digital telemetered station, two USNSN stations received by VSAT telemetry, and four broad-band dial-up stations (data recovered within minutes after events of interest).

Data from an experimental packet-radio seismograph station in Canada are being received in a test mode.

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