> This page is for version 1.4.0 (Latest) (default).
> For other versions, use one of these documentation indexes:
> - 1.4.0 (Latest) (default): https://docs.nvidia.com/halos/outside-in-safety/1.4.0/llms.txt

> For clean Markdown of any page, append .md to the page URL.
> For a complete documentation index, see https://docs.nvidia.com/halos/outside-in-safety/llms.txt.
> For AI client integration (Claude Code, Cursor, etc.), connect to the MCP server at https://docs.nvidia.com/halos/outside-in-safety/_mcp/server.

# Safety Core Components

> The components of the Safety Core, what each one does, and the page that describes it.

The Safety Core is the set of processes and libraries between the perception pipeline and the
machine controller. Each component page describes the component's role, configuration and
failure behaviour, and includes its architecture diagram where one applies. How the components
connect, where each one runs and how they talk to each other is described in the
[Integration Guide](/halos/outside-in-safety/integration).

## Components

| Component                               | Binary                                                       | Role                                                                                                                                                                 | Details                                                                                           |
| --------------------------------------- | ------------------------------------------------------------ | -------------------------------------------------------------------------------------------------------------------------------------------------------------------- | ------------------------------------------------------------------------------------------------- |
| Sensor Input Processing Pipeline (SIPP) | Not part of the Safety Core                                  | The perception stack, for example VSS. It publishes detections and alerts to Kafka.                                                                                  | [SIPP](/halos/outside-in-safety/integration/components/sensor-input-pipeline)                                             |
| MDX client                              | `mdx_client`                                                 | Reads perception messages from Kafka, maps them to safety events with an event-mapping file, and reports them to the SEI.                                            | [SIPP](/halos/outside-in-safety/integration/components/sensor-input-pipeline)                                             |
| Safety AI Monitor (SAIM)                | `safety_monitor`                                             | Watches each camera stream and reports `SENSOR_INVALID` or `SENSOR_VALID` per camera.                                                                                | [SAIM](/halos/outside-in-safety/integration/components/ai-monitor)                                                        |
| Perception Container Monitor (PCM)      | `nv_perception_monitor`                                      | Watches the perception containers and their output, and reports `AI_PIPELINE_INVALID` or `AI_PIPELINE_VALID`.                                                        | [PCM](/halos/outside-in-safety/integration/components/perception-monitor)                                                 |
| Safety Event Integrator (SEI)           | `nvpss_daemon`                                               | Validates every report, applies the trust verdicts, fuses events, supervises its sources, and produces decision requests.                                            | [SEI](/halos/outside-in-safety/integration/components/event-integrator)                                                   |
| NvPSD Gateway                           | `nvpsd_gateway`                                              | Admits decision makers, filters each request to what each one subscribed to, numbers the stream, and reports faults on its own link to the SEI.                      | [NvPSD Gateway](/halos/outside-in-safety/integration/components/gateway)                                                  |
| Safety Decision Maker (SDM)             | `atl_sdm`, `proximity_sdm`, `atl_proximity_sdm`, or your own | Decides what the machine may do, latches a safe state on any fault, and commands the PLC.                                                                            | [SDM](/halos/outside-in-safety/integration/components/decision-maker)                                                     |
| FSI bridge                              | `fsicom-agent`                                               | Connects an SDM running on the Functional Safety Island (FSI) of IGX Thor to the gateway and the PLC.                                                                | [Writing a decision maker](/halos/outside-in-safety/integration/writing-a-decision-maker#sdm-on-the-fsi)                  |
| Command receiver                        | `atl_sdm_cmd_receiver`, `proximity_sdm_cmd_receiver`         | Reference stand-in for the PLC.                                                                                                                                      | [Writing a decision maker](/halos/outside-in-safety/integration/writing-a-decision-maker#the-reference-command-receivers) |
| Safety Black Box (SBB)                  | `libnvpsb.so`                                                | The syslog-based record library used by the SEI daemon, the gateway, the MDX client and the SEI client library. The SDMs and the monitors write their own log files. | [SBB](/halos/outside-in-safety/integration/components/black-box)                                                          |
| Safety User Interface (SUI)             | —                                                            | Not implemented.                                                                                                                                                     | [SUI](/halos/outside-in-safety/integration/components/user-interface)                                                     |

SIPP and the SDM are specific to a use case. SAIM, PCM, the SEI, the gateway and the SBB are the
same for every use case.