There are four basic ways in which your device may communicate with another computer on the Web:
Device is the client, pushing data to a server
Device is the client, pulling data from a server
Device is the server, providing data to clients
Device is the server, accepting data from clients
These patterns can be visualized as shown in Figure 4-5. A black arrow indicates the direction of a request message and a dotted arrow indicates the direction in which data flows, i.e., in which direction a resource representation is sent.
Figure 4-5. Four basic web interaction patterns
In monitoring applications, a device produces data, i.e., measurements ...