This page compares micro-ROS to a few alternative approaches.

In ROS1, small embedded devices are brought into the system using `rosserial`.

Differences are:

| | rosserial | micro-ROS |

|-------|-----------|-----------|

| OS | bare-metal | POSIX (currently NuttX) |

| Communications architecture | Bridged | Bridged |

| Message format | ROS1 | CDR (from DDS) |

| Communication links | UART | UART, SPI, IP (UDP), 6LowPAN, ... |

| Communication protocol | Custom | XRCE-DDS (or any rmw implementation) |

| Code Base | Independent implementation | Standard ROS2 stack up to RCL (RCLCPP coming) |

| Node API | Custom rosserial API | RCL (soon RCLCPP) |

| Callback execution | Sequential, in order of messages | Choice of ROS2 executors or MCU optimized executors |

| Timers | Not included | Normal ROS2 timers |

| Time sync to host | Custom | NTP/PTP |

| Lifecycle | Not supported | Partial, full coming |