We are evaluating a setup involving more than one STTP client connecting to the same openPDC instance using the default STTP port (7165), each client subscribing to different sets of PPAs for distinct purposes (e.g., full archival versus statistical processing).
Our current assumption is that openPDC publishes each measurement only once to the STTP endpoint (port 7165), and that any filtering or selection of PPAs is performed entirely by the client applications (such as OH2 ingestion or custom STTP consumers), rather than at the server level. – But we are not sure.
Based on this assumption, we would like to clarify the following points:
- Does openPDC internally replicate and dispatch the same measurement stream independently for each connected STTP client, or is there a single publication pipeline shared across all connections?
- For PPAs that are subscribed by more than one client, are the timestamps and delivery instants identical from the server’s perspective?
- Is there any internal sequencing, prioritization, or ordering effect between different STTP connections, or should all clients be treated as logically independent consumers of the same published measurements?
In summary, we are trying to understand whether multiple STTP clients connected to the same port should be considered concurrent consumers of a uniquely published measurement stream, or if there is any per-connection serialization that could affect timing or ordering.