An Introduction to oneM2M's Architecture

This article presents a basic overview of the oneM2M Common Service Functions (CSF) and its architecture and main components. Also, some of the important abbreviations used in oneM2M are explained.

oneM2M Common Service Functions

The oneM2M architecture is based on the concept of Common Service Functions (CSF) for IoT applications that are provided by a Common Service Entity (CSE). A CSE can be implemented in many different ways, for example as a cloud service, on a gateway device, or on a capable IoT device.

Figure 1: oneM2M Common Service Functions¹

A CSE provides a set of common services for IoT applications. Examples for such services are:

Data management: A CSE provides a set of services for storing, retrieving, and managing IoT data. This includes services for storing, retrieving and managing IoT data.
Device management: Another common service function is the management of IoT devices. This includes services for registering IoT devices and managing IoT devices.
Security: An important part is the set of functionalities for securing IoT data and providing access control within a oneM2M system which is provided by a CSE.
Communication: A CSE provides a set of services for communicating within an oneM2M deployment and with IoT devices. This includes services for sending and receiving IoT data, for managing IoT device communication channels, and for managing IoT device communication protocols.
Discovery: oneM2M provides services for discovery services for IoT devices and IoT data within a oneM2M system. This includes also Semantic discovery services.

and many more.

oneM2M Architecture

The following figure shows the basic architecture of oneM2M.

The middle layer (in red) represents the Common Service Entities (CSE) and its Common Service Functions (CSF). The CSE provides the common services for IoT applications called Application Entities (AE, in blue).

At the bottom the Network Service Entity (NSE, in grey) provides network services for the CSEs. The details of the NSE are not part of the oneM2M standard, but it is an important part of the oneM2M architecture. The NSE provides the connectivity services for the CSEs. This includes services for connecting CSEs and IoT devices to each other, and also provides services to manage network resources and connected devices as well as to provide network security.

Figure 2: oneM2M Common Service Functions²

Entities

The following table lists the abbreviations used in the oneM2M architecture.

Entity	Abbreviation	Meaning
Application Entity	AE	Provides application logic for the end‐to‐end M2M solutions
Common Services Entity	CSE	Provides the set of “service functions" common to the M2M environments
Network Services Entity	NSE	Provides connectivity services to the CSEs besides the pure data transport
Node		Logical equivalent of a physical (or possibly virtualized) device

Reference Points

The oneM2M architecture defines a set of reference points that are used to describe the RESTful interfaces between the different components of a oneM2M system. Figure 2 shows the reference points of the oneM2M architecture. They start with the letters Mc and are followed by a letter that indicates the direction of the interface.

The following table lists the reference points and their meaning.

Reference Point	Meaning
Mca: CSE - AE	Interface between a CSE and an Application Entity
Mcn: CSE - NSE	Interface between a CSE and the Network Service Entity
Mcc: CSE – CSE	Interface between two CSEs
Mcc’	Interface between two service providers.

by Andreas Kraft, 2023-11-16

Source: oneM2M ↩
Source: oneM2M ↩