The Design of the BSN Gateway for Gumstix
This page illustrates the high level configuration of the IEEE 802.15.4 gateway and the temperature sensor. The IEEE 802.15.4 gateway translates serial messages from the policy service, i.e., the gumstix to IEEE 802.15.4 packets and then sends them off. Additionally, it receives IEEE 802.15.4 messages from other BSNs and translates them into serial messages.
serial messages IEEE 802.15.4 packets SMC (gumstix) <-------------------> IEEE 802.15.4 gateway <-------------------------> temperature sensor (BSN)
The following figure shows the configuration of the IEEE 802.15.4. It uses the GenericComm component to send, receive serial and IEEE 802.15.4 packets.
http://www.doc.ic.ac.uk/~slk/images/uart.jpg
The configuration of the temperature is slightly more complicated as it uses more components. The core components for a managed resource include, discovery, event service and sense components. The discovery component is responsible to respond to the discovery messages broadcast by the SMC and periodically sending a HELLO message to the SMC in order to maintain its membership. The event service generates events whenever the sense component observes that the temperature has exceeded certain threshold. The TemperatureSensorM component coordinates the interactions among the discovery, event service and the sense components. Broadcast and unicast messages are received via the GenericComm component and based on the packet type, they are forwarded to the appropriate component for further processing.
http://www.doc.ic.ac.uk/~slk/images/temperatureSensor.jpg
