An apparatus may contain an embedded controller or agent software to monitor and control its operation. Any type of apparatus may have an embedded controller or agent including, but not limited to, home appliances, office equipment, medical devices, and industrial tools. Other examples include robots, blood analyzers, multifunction copiers, and air conditioners.
Embedded devices are often connected to an internal network, such as a local area network (LAN), with an interface to the Internet. Other devices on the internal network may communicate with an embedded device over the internal network. However, the embedded device is not generally addressable from the Internet. To address this problem, the embedded device may initiate communications with an addressable external device. That is, the embedded device may access the external device (e.g., a server) periodically to obtain necessary data.
SOAP is a standard for encoding function calls, such as remote procedure calls (RPCs), in XML. SOAP defines rules, i.e., a syntax, for encoding the function calls in XML. The body of a SOAP command is defined, at its start, by <SOAP-ENV:BODY> and, at its end, by </SOAP-ENV:BODY>. Code in between these two commands includes the function to be performed by the SOAP command. A SOAP command may include other data as well, such as header information.