Earth Notes: OpenTRV Protocol Discussions Part 1 (2014-11)

Updated 2019-07-11 07:56 GMT.
OpenTRV archival data format, radio/wire comms format, and other issues.
data
Discussions and decisions on IRC, including that TinyHAN MAC should be preferred local RF MAC layer, we will use it to support JSON-/Mike-/binary- format frames, all full timestamps at and beyond the concentrator to be in unambiguous ISO-8601 UTC with variable precision from just years down to many decimals of seconds as appropriate to the data.

Some items up for discussion:

See the IRC transcript for the session of the evening of 2014-11-13.

Some decisions from the IRC chat:

  1. [Decision] TinyHAN MAC should be preferred local RF MAC layer for OpenTRV and the generic sensor platform ...
  2. ... and we will use it to support JSON-/Mike-/binary- format frames (Mike format draft spec: Mike's copy and local copy filed 2014-11-13).
  3. [Decision] All full timestamps at and beyond the concentrator (leaf nodes need not timestamp their messages at all) in sensible unambiguous ISO-8601 UTC showing the 'Z' timezone to be clear not local time (Can be displayed in local timezone as required)
  4. ... and with variable precision from just years down to many decimals of seconds as appropriate to the data, ie truncated on the right, with years always 4-digit; week notation also allowed.

Some issues touched on and/or to be discussed next time:

Postscript

As of 2018 we're fairly content with our use of JSON and something close to UCUM for over-the-air real-time data and long-term storage, and secure enough (AES-GCM protected) frames to be safely tunnelable through a data relay and across the Internet, at least for now!