@@ -188,8 +188,13 @@ The IPE shall map the 'result' attribute of an OGC/STA 'Observation' to the 'con
## 6.2 Communication Schema
In order to transfer data from a oneM2M sensor to OGC/STA the IPE creates a <subscription> to the <container> resource with the desired data and when a new <contentInstance> is added it gets a <notification> message containing the <contentInstance> resource.
Figure 6.2-1 shows the oneM2M-to-OGC/STA direction. Based upon the creation of the <contentInstance> in the hosting CSE, the IPE gets a <notification>> message including the <contentInstance>. The IPE constructs an "Observation" creation request and copies the 'content' attribute of the <contentInstance> to the 'result' attribute of the "Observation" shown in Figure 6.2.2.0-2 and sends it to the OGC/STA server.
Figure 6.2-1 shows the oneM2M-to-OGC/STA direction. Based upon the creation of the <contentInstance> in the hosting CSE, the IPE gets a <notification> message including the <contentInstance>. The IPE constructs an "Observation" creation request and copies the 'content' attribute of the <contentInstance> to the 'result' attribute of the "Observation" shown in Figure 6.1-1 and sends it to the OGC/STA server.
Figure 6.2-2 shows the OGC/STA-to-oneM2M direction. OGC/STA does not provide a publish/subscribe mechanism on HTTP protocol level, but OGC allows an optional MQTT extension for STA services <ahref="#_ref_i.1">[i.1]</a>. The IPE subscribes to the MQTT-Broker of the OGC/STA server. The OGC/STA server publishes its new "Observation" via the MQTT broker. The IPE creates a <contentInstance> using a HTTP request and copies the 'result' attribute of the "Observation" to the 'content' attribute of the <contentInstance>. The <container> may be created beforehand at the hosting CSE where the IPE <contentInstance> resources are stored. All interested applications may subscribe to this <container> resource.
