# Earthworm Modules:
Latency Monitor Overview

(last revised 1 June, 2006)

This program takes waveforms dropped in InRing and logs latency and outages of the data. Each time a trace arrives, its start time is compared to the end time of the last packet. When there is a gap the outage is logged to a data file for that station. Also, the start time is compared to real-time, and latency is determined. Whenever the latency changes, it is also logged with start and end time to the file. Latencies are grouped generally: <1' = 0; 1'-2' = 1; 2'-3' = 2; 3'-5' = 3; >5' = 4. Here, latency is described as present time minus mid-time of the packet.

The graphical output shows a line for each station in the .sta file for a set length of time. Colors on the line represent the latency of the station over that time interval.

This will only give accurate outage values if this module is running all the time the earthworm system is up.

This module is strictly for use under Windows.

Written by Paul Whitmore, (WC/ATWC) August, 2001 Modified by John Patton (USGS) July, 2002

      Usage:  get_latency <name of configuration file>

Module Index | Latency_mon Command File