Concepts
########

Components
==========

Proto
-----

* https://github.com/open-telemetry/opentelemetry-proto


Specification
-------------

Beyond definition of terms, the specification defines the following::

    1. API: 
      Used to generate telemetry data. 
      Defined per data source as well as for other aspects including baggage and propagators.
    2. SDK: 
      Implementation of the API with processing and exporting capabilities. 
      Defined per data source as well as for other aspects including resources and configuration.
    3. Data: 
      Defines semantic conventions to provide vendor-agnostic implementations 
        as well as the OpenTelemetry protocol (OTLP).

Collector
---------

The OpenTelemetry Collector offers a vendor-agnostic implementation on how to receive, process, and export telemetry data.


Components
^^^^^^^^^^

The Collector is made up of the following components::

    1. receivers: How to get data into the Collector; these can be push or pull based
    2. processors: What to do with received data
    3. exporters: Where to send received data; these can be push or pull based

.. note:: These components are enabled through pipelines. Multiple instances of components as well as pipelines can be defined via YAML configuration.


Deployment
^^^^^^^^^^

two primary deployment methods::

    1. Agent
        A Collector instance running with the application 
          or on the same host as the application (e.g. binary, sidecar, or daemonset).
    2. Gateway
        One or more Collector instances running as a standalone service (e.g. container or deployment) 
          typically per cluster, datacenter or region.





Instrumentation Libraries
-------------------------

The inspiration of the OpenTelemetry project is to make every library and application observable out of the box by having them call the OpenTelemetry API directly.