# EARTHWORM Status Report

##### `Feb. 12, 1998`

#### This is an update of Earthworm status since the notes of 9/25/97.

The Earthworm community is alive and growing. The number of participants is growing and, more significantly, so is the number of sites participating in development. Currently, eight individuals at UofW Seattle, PNL Richland, USGS Menlo Park, ATWC Palmer, and USGS Golden are actively participating in design, implementation, modifications, and testing. This group has been keeping in touch via

email, individual phone calls, and a weekly conference call meeting. This has resulted in a very effective development team, especially when one considers that we're spread over three time zones, several thousand miles, and report to six different supervisors. The benefits have been to (1) accelerate progress by sharing specialized knowledge, (2) provide a very rapid mechanism for isolating and fixing bugs, (3) identify and implement mutually desired enhancements, and (4) assure that new designs are as generally useful as possible.

### CURRENT DIRECTIONS:

- 1. NOAA-USGS Tsunami project: This has been one of the main objectives. Work to date consisted of installation of systems at the Alaska Tsunami Warning Center (ATWC) in Palmer Alaska, UofW in Seattle, USGS Menlo Park, and an installation is in progress at PGC British Columbia. The result is that ATWC is receiving trace data from IDA, USNSN, Menlo Park, and Seattle. All data are interfaced to ATWC's existing processing system. In addition, hypocentral parameters are being received from Menlo Park and Seattle. Our current installation there consists of two computers: a Sparc Ultra, which acts as their 'loading dock', and an NT Intel machine which digitizes local analog data and runs the core ATWC functions. The digital data are currently being shipped via a combination of public Internet and DOI net, which, as expected, has proven to be a rich source of rare link failure-modes, and has thus provided a good test-bed for debugging and ruggedizing our communications software. Work is continuing, as described below.

- 2. Support of regional networks: This has focused on support of individual installations, and 'completion' of Earthworm, in terms of interactive analysis and archiving. The work done at the University of Fairbanks (IceWorm) has resulted in an excellent integration of the DataScope interactive analysis package. The approach here has been to create 'connector' software, which facilitates interfacing Earthworm to various interactive analysis schemes already in use at various sites. An interface to the UofW 'uw2' format has been completed, and a SAC interface is in progress. The object is to be in position to accommodate pre-existing interactive analysis packages, as well as being able to offer a variety of pre-integrated options. A number of site visits have been scheduled with the objective of discussing areas in which we can be of service, and to produce task lists and schedules.

- 3. EWAB: We have responded to the EWAB request for documentation (see below); in addition, a 'request for comment' (RFC) mechanism is being created to coordinate development efforts at various sites. The objective is to assure that the whole community be aware of various planned and ongoing developments, and that there be an opportunity to submit comments which will be considered by the developing institution. The hope is that this will permit sharing of programming talent and software components, and will result in modules, which will be of more general utility.

### RECENT DEVELOPMENTS:

- Socket utility routines: Our experiences with long-distance, long-term socket connections, multi-threaded servers, automated client programs as well as the seamy underside of NT and Solaris 2.6, have led us re-write our socket utility routines. This new suite features user-specified timeout values and proper operation on Solaris and NT.

- WaveServerV: This is an enhancement of WaveServerIV. The additional features are a robust crash-recovery scheme, incorporation of the new socket routines (see above), performance enhancements, and bug fixes.

- WaveClientII: This is a set of utility routines to ease creation of WaveServer clients. This set replaces the earlier, simpler such set, and features a wider variety of services for both 'simple' and 'sophisticated' client programs, is multi-thread safe, and utilizes the new socket routines (see above).

- 'UW2' interface: An interface between Earthworm and the University of Washington 'uw2' interactive analysis package has been completed. The routine is executed either automatically or manually, takes either Earthworm 'trigger' messages or UW2 format pick files, and constructs the UW2 event files by accessing a specified list of WaveServers. This routine is the first use of a series of utility routines, which will permit quick integration with other interactive analysis formats.

- SAC interface: Work is about to start on an interface to SAC, modeled on the UW2 interface code, above. The next task is to submit to the EWAB a request for comment (RFC). The plan is to collect the responses, produce an implementation plan, which addresses the comments, and to start implementation of a first version module.

- CarlTrig: Named in honor of its perpetrator, this is a port of the traditional STA/LTA trigger algorithm as popularized by Carl Johnson. The initial version is nearing completion. The motivation was to provide a more conservative method of saving event data than via hypo-inverse solutions. This module generates 'trigger' messages, the same as those generated by hypoinverse solutions (arc2trig), or the John Evans long period coincidence detector (lptrig). This initial version features subnet logic, and may include individual station trigger parameters and inclusion of delayed data. An RFC is being prepared to provide the specs for future versions.

- Documentation: An overview document, module descriptions, and sample parameter files have been submitted to the EWAB, and have been posted on the CNSS site. This is an ongoing process; additional descriptions are being prepared. It has been noted that there is currently a discontinuity between the overview document and the descriptions of individual modules. It is agreed that there should be a section explaining more about the various components of Earthworm, and an explanation of how they interact. It has been suggested that this could be done via several examples, stating the problem to be solved, a diagram of an Earthworm construction to solve the problem, and an explanation of how the various components of the construction would interact. Further comments and contributions are welcome.

- RCV: RCV, the USNSN computer code which receives USNSN data has been encapsulated into an earthworm module. The approach here has been to encapsulate the existing RCV code with no modifications. Thus, as the USNSN produces internal enhancements to RCV, the new code can be moved directly into this module. Modifications affecting the external behaviour, will, of course, require a change to the encapsulating wrapper. This connects to the USNSN system in Golden, CO and receives triggered, compressed trace data, possibly out of sequence. The USNSN system in Golden controls which stations are sent. The encapsulating wrapper decompresses the data, re-sequences the data (as permitted within a user-specified time limit), and produces a stream of standard Earthworm trace data messages. This is currently installed and undergoing testing between the USNSN Golden and ATWC in Palmer. It appears that RCV may require some minor enhancements to make it more robust, and USNSN has agreed to work on this. It is expected that this module will be documented and released as part of Earthworm after it has demonstrated acceptable performance.

- import_IDA: A similar encapsulation has been done for the receiver of IRIS/IDA data from UCSD. A module description document is being produced.

### FUTURE DIRECTIONS:

- Tsunami: This will continue to be a large effort. Upcoming tasks include implementing a list of enhancements for ATWC, generating a second-generation bug- and enhancement list based on experience with the current installation at ATWC, installation of dedicated communication links, integration of data acquisition from several types of data loggers, and installation and testing of a redundant system.

- DBMS: Phase II work is about to begin. This includes evaluation and selection of suitable data structures, the production of a working system capable of acquiring and storing real-time data in a commercial data base, providing operator displays and controls, and to provide interactive access to the data which permits modifications, additions, and archiving of the stored data.

- Complete Earthworm: Work toward making Earthworm a complete network processing system capable of rapid exchange of data with other sites, and offering a suite of interactive analysis tools suitable for low-level routine processing as well as research support.

- Regional support: Assist various regional networks as required to help them meet their goals.

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