.. _observer:

Passive Observation
===================

The passive observation modules (sometimes referred to as "observer chains")
are used by the active measurement plugins, but can also be used independently.
At this time, it is not possible to create new passive observation modules
as plugins unless they are part of an active measurement plugin.

A number of modules ship with the PATHspider distribution. You can find their
documentation here:

.. toctree::
   :glob:
   :titlesonly:

   chains/*
