# Nodes and Connections ## Node Palette

Description	When to use	Example
Person Customers or stakeholders	You want to model people's actions, permissions, or decision points.	A person logging into an admin dashboard, approving a workflow, or sending a secure message.
Entity Business entities or AIs	You need access for AI agents, companies, tenants, departments, identity domains.	A healthcare provider, an insurance company, or a tenant account applying its own access rules.
Thing Physical or digital objects/devices	You’re modelling hardware, IoT devices, sensors, servers, or edge components.	A smart meter sending readings, a kiosk receiving updates, or a server reporting health status.
Process Business processes or Agentic workflows	You want to show business logic, transformations, or background tasks.	A data validation step, a policy enforcement engine, or a message-routing workflow.
API External systems or platform integrations	You’re integrating with third-party services or exposing functionality programmatically.	A payment processor API, mapping service, or internal microservice endpoint.
Other Custom node type for anything else	You need to include concepts like storage, policies, models, or abstract systems.	A policy store, encryption module, AI model, or logging system.

## Connection Types {% hint style="warning" icon="lightbulb" %} If you are unsure, you can use Data Stream. {% endhint %}


Async Comms	Asynchronous, non-blocking communication where the sender does not wait for a response and the receiver does not need to be online. Uses `Get/Put` semantics. Read more here.	Really handy if you cannot guarantee both the sender/ receiver will be online at the same time.	A device uploads data that is processed later, or a message is delivered when the recipient comes online.
Sync Comms	Synchronous communication where the sender waits for an immediate response. Uses `Notification` (Read more here) semantics and/or `Get/Put` (Read more here) semantics.	You need real-time interaction or confirmation.	A user request that must return a result immediately, like fetching account details_.
Notifications	One-way signals used to alert or inform. Uses `Notification` semantics Read more here.	You need to notify without requiring a response.	Push notifications, system alerts, or status updates sent to users or services.
RPC	Structured request/response interactions between systems. Ideal for complex operations where the other party may not be online at the time of execution (especially useful for policy-driven workflows). Supported in the `SDK` semantics. Read more here.	You want function-like calls across services with clear inputs and outputs.	Calling a billing service to calculate charges or a policy engine to validate access.
Data Stream	Ideal for long-running processes (such as LLM generation) where completion time is uncertain and results may need to stream incrementally. Uses the `stream` (Read more here) semantics or `notifications` (Read more here) semantics.	You’re handling live, ongoing data rather than discrete messages	Telemetry feeds, sensor data, logs, or real-time analytics pipelines.
TCP	Low-level, persistent network connections that enable lower latency communication (e.g., NoPorts SSH, MCP servers). Uses `Noports_Core` (Read more here) semantics.	You need a fast end-to-end encrypted TCP connection with raw network speed.	A custom protocol, legacy integration, or long-lived secure connection.

RPC