diff --git a/TS-0041-oneM2M-SensorThings_interworking.md b/TS-0041-oneM2M-SensorThings_interworking.md index 1c1e46fbb6fd976fe6a3d9205aa401e8ca4fb529..5dad3a28920b0720cc33ed0bd383afb5a2977d08 100644 --- a/TS-0041-oneM2M-SensorThings_interworking.md +++ b/TS-0041-oneM2M-SensorThings_interworking.md @@ -61,6 +61,7 @@ References are either specific (identified by date of publication and/or edition - <a name="_ref_1">[1]</a> OGC SensorThings API "Part 1: Sensing Version 1.1" (http://www.opengis.net/doc/is/sensorthings/1.1) - <a name="_ref_2">[2]</a> oneM2M TS-0033 (V3.0.0): "Interworking Framework" +- <a name="_ref_3">[3]</a> oneM2M TS-0001 (V4.23.0): "Functional Architecture" ## 2.2 Informative references @@ -163,11 +164,11 @@ The Sensing Entities data model and the purpose of data within the data model di # 6 Architecture Model of OGC/STA to oneM2M interworking -## 6.0 Introduction +## 6.0 Overview Figure 6.0-1 shows an architecture approach for an Interworking Proxy Entity (IPE) between oneM2M and the OGC SensorThings API. The IPE is located between a oneM2M CSE and an OGC/SensorThings API (STA)-Server. -The basic interworking enables applications that are connected to an oneM2M-based system to get data from sensors that are connected to an OGC/STA server. Furthermore, an application that is connected to an OGC/STA server will be able to get data from sensors that are connected to an oneM2M-based system. +The basic interworking enables applications that are connected to an oneM2M-based system to get data from sensors that are connected to an OGC/STA server. Furthermore, an application that is connected to an OGC/STA server will be able to get data from sensors that are connected to an oneM2M-based system. The communication flow of the IPE shall rely on HTTP and MQTT. The MQTT protocol enables publish-subscribe functionality for the OGC side, as specified in the MQTT extension of the SensorThings API <a href="#_ref_i.1">[i.1]</a>.  @@ -179,12 +180,28 @@ According to oneM2M TS-0033 <a href="#_ref_2">[2]</a> a representation of a non- - sensor (IoT-data); and - administrative data (like historic locations or historic products IDs). -The IPE shall map the 'result' attribute of an OGC/STA 'Observation' to the 'content' attribute of a oneM2M <contentInstance>, and vice versa as shown in Figure 6.1-1. +The IPE shall map the 'result' attribute of an OGC/STA 'Observation' to the 'content' attribute of a oneM2M `<contentInstance>`, and vice versa as shown in Figure 6.1-1. The data type of the 'result' field of an "Observation" is according to SensorThings API <a href="#_ref_i.1">[i.1]</a> 'any' and depends on the 'observationType' defined in the associated "Datastream". The 'content' attribute of an oneM2M instance may be stringified data <a href="#_ref_3">[3]</a> understandable with the help of the 'contentInfo' attribute. The 'contentInfo' attribute on the oneM2M side may be added by the IPE. The original timestamps, present in the "Observation" as 'phenomenonTime' and in the `<contentInstance>` as "creationTime," shall be discarded. These timestamps are to be reset by the OGC /STA server and the CSE. They may be transmitted for informational purposes as part of the 'result' or the 'content' fields.  **Figure 6.1-1: OGC / STA-to-oneM2M data model mapping** +## 6.2 Communication Flow + +Figure 6.2-1 shows the oneM2M-to-OGC/STA direction. In order to transfer data from a oneM2M sensor to the OGC/STA server the IPE creates a `<subscription>` to the `<container>` resource in the CSE containing the desired data. Triggered by a sensor event a new `<contentInstance>` is added to the `<container>` by the `<AE>`. The IPE gets a `<notification>` containing the `<contentInstance>` resource. +The IPE constructs an "Observation" creation request and copies the 'content' attribute of the `<contentInstance>` to the 'result' attribute of the "Observation" and sends it to a "Datastream" to be created as detailed in Section 6.3.1 at the OGC/STA server. The OGC/STA applcation gets the sensor data either by polling the OGC/STA server or subscribing to the corresponding "Datastream" at the MQTT broker of the OGC/STA server. + + + +**Figure 6.2-1: Communication oneM2M-to-OGC/STA direction** + +Figure 6.2-2 shows the OGC/STA-to-oneM2M direction. The IPE subscribes to the desired "Datastream" of the MQTT-Broker at the OGC/STA server. The OGC/STA server publishes a new "Observation" via the MQTT broker triggered by a OGC/STA sensor. The IPE creates a `<contentInstance>` in a container, to be created as detailed in Section 6.3.2 in the CSE and copies the 'result' attribute of the "Observation" to the 'content' attribute of the `<contentInstance>`. The oneM2M applcation gets the sensor data either by polling the CSE or subscribing to the desired `<container>` at the CSE. + + + +**Figure 6.2-2: Communication OGC/STA-to-oneM2M direction** + + <mark>The following text is to be used when appropriate:</mark> diff --git a/media/com_flow_1.png b/media/com_flow_1.png new file mode 100644 index 0000000000000000000000000000000000000000..45d6f7b2ff7cff3b79a7c7e1665476bcef07302a Binary files /dev/null and b/media/com_flow_1.png differ diff --git a/media/com_flow_2.png b/media/com_flow_2.png new file mode 100644 index 0000000000000000000000000000000000000000..71ce16d3fc670dcc43e7782c3a58098ecf8bf0b4 Binary files /dev/null and b/media/com_flow_2.png differ diff --git a/media/config.png b/media/config.png new file mode 100644 index 0000000000000000000000000000000000000000..b74bfd68183b936fe76b5fa4fe5d994b424dc793 Binary files /dev/null and b/media/config.png differ diff --git a/media/config_ogc.png b/media/config_ogc.png new file mode 100644 index 0000000000000000000000000000000000000000..8c12246ccc79e918bb313447cc8eba244ce52b97 Binary files /dev/null and b/media/config_ogc.png differ