# IoT OS Platform: Software Infrastructure for Next-Gen Industrial IoT
## 3 Theoretical Framework of the IoT OS Platform
### Core Design of the IoT Operating System Platform
#### 3.2.1 Connectivity  
Based on the direction of data flow, we categorize heterogeneous devices in the IoT into sensors and actuators. Sensors are devices that sense data and send it to the platform, while actuators respond to platform data. The ability to connect sensors and actuators is a foundational capability of the IoT OS platform. This requires the platform to have the capability of pluggable custom protocol parsing methods and adaptive matching communication methods, to access the devices of different communication methods, protocols, and brands. Supporting different protocols is a prerequisite for managing heterogeneous devices and is also one of the foundational capabilities of the IoT OS platform. This capability can improve device compatibility, reduce development difficulty, simplify management operations, and enhance communication efficiency and reliability, thereby achieving interoperability between devices. However, the IoT features a variety of transmission protocols and protocol carriers. Unlike internet transmission protocols, which focus on standardization and high speed, IoT applications prioritize transmission stability, reliability, and real-time performance [17], requiring transmission can still operate normally in relatively harsh environments. Additionally, IoT devices often lack computing resources and have limited transmission capabilities. In addition to resource-rich devices that support TCP/IP-based network protocols, many IoT devices only support field protocols [17]. The connectivity capability of the IoT operating system platform parallels the device management capability of traditional operating systems. In traditional operating systems, device management is used to uniformly manage and control external I/O devices. Considering the diversity and differentiation in IIoT scenarios, in the theoretical framework of the IoT OS platform, we generalize the definition of I/O devices to physical entities capable of data reading and writing (such as sensors and actuators) or abstract informatized entities representing physical entities (such as external systems or databases). In traditional IoT system construction, there is a lack of unified, standardized devices and they usually cannot integrate with existing informatization systems. This prevents the reuse of previous digital achievements when advancing industrial digital construction, and newly constructed IoT systems cannot retain forward compatibility for future new demands [47]. Inspired by the architecture of traditional operating systems, the theoretical framework of the IoT OS platform constructs connectivity capabilities, shielding the heterogeneity and differentiation of lower-layer entities from upper-layer applications. Through differentiated analysis and unified management, we achieve entity management with forward compatibility, as illustrated in Figure 2.  
**Differentiated Analysis. ** In traditional operating systems, to achieve complete interaction with external I/O devices, it is necessary to build device drivers targeting differentiated external I/O devices, acting as a bridge between the operating system and hardware devices, converting communications between the operating system and hardware devices into control signals required by the devices [48]. Similarly, in the IoT OS platform, interacting with differentiated external entities also requires building specific data parsing functions. Although IIoT entities lack a unified standard, they all fundamentally involve data I/O based on bits or bytes [49]. Currently, entities involved in IIoT scenarios have two characteristics: the enumerability of network connection protocols and the inenumer  
Figure 1: Theoretical architecture of IoT OS platform. ability of specific semantics. Considering that communication is composed of composite network protocol stacks, most protocols can be pre-integrated through open standards at the technical level.