Communication layer

Quatm’s services communicate over ZeroMQ. The design keeps the timing path independent of rendering, and makes local and remote clients interchangeable.

Hubs and streams

Each data type has a Hub that collects and redistributes messages:

• scalar data streams;
• image streams;
• command channels;
• property updates;
• messages and logs.

Clients connect to the Hubs they need. A client process does not need to know which other clients exist, and a Hub failure is visible and restartable.

Client types

Properties

The property tree is the shared configuration and state model. Properties are read and written by name through a filesystem-like path; the Property Logger persists the tree and applies the persistence policy. GUI panels, web dashboards and experiment code all read the same values.

Remote property writes use a persistent publisher and explicit acknowledgement, so a remote action is not silently lost when a connection is slow.

Transport choices

• IPC for processes on the same machine (lowest latency).
• TCP for split control/analysis machines and remote clients.

Curve encryption is available for local and network channels. The transport layer also handles multipart framing, malformed-frame recovery and request timeouts.

Configuration

Endpoints, project root and service selection are read from the project’s configuration/ directory. A service can be launched by the Operations Console, by a project launcher, or directly as a Python module for debugging.