in our current fiware setup (only Orion) we would like to store the history of contexts. I know QuantumLeap and Cygnus and unsure know which one is designed for that.
My current understanding:
QuantumLeap: store time-series data which can be queried by time - and optional some more data
Cygnus: write history of specific contexts (i.e. a parking spot) and fetch the history of that parking spot
Could someone help me there?
Both are valid.
Cygnus persists the information into several databases (for NGSIv2 e.g.m HDFS, MySQL, MongoDB, DynamoDB, PostgreSQL, or Elasticsearch among others; for NGSI-LD e.g., PostgreSQL and PostGIS).
QuantumLeap persists the historical information into CartoDB using NGSIv2. NGSI-LD is currently experimental choice.
Therefore, the selection is usually conditional on which database and which version of the NGSI API you want to use in your concrete case.