Unformatted text preview: ce source can select up to XLIDs to route I-message back to the sink based on QoS requirement The max value of x is the number of neighbor nodes Each DLID value corresponds to a DSP indicator In the T-tree, the leaf nodes has no ULID and NS indicator since sources are destination of S-message A source can receive xS-message since it has x neighbors Route associated with the first received S-message is considered shortest route Sources selects neighbor node to send I-message back to sink based on the QoS requirement of INS SER
2. Route Selection Once the sources receive the S-message, they determine the QoS requirement of task in the S-message There are four types of streams for communication between sources and sinks and each stream can either be level-1 or level-2: Type 1: Time Critical But Not Data Critical Type 2: Data Critical But Not Time Critical Type 3: Not Time and Data Critical Type 1: Data and Time Critical After the sources select the neighbor nodes, the sources broadcast an N-message to their neighbors indicating the level and size of the stream N-message contains the following fields: TID NAP LID SLID MES SLID: Selected ID MES: Message SER
2. Route Selection If stream is level-1, = 0 (width of the stream) At level-1, messages are routed back to the sink via hop-by-hop communication. Message are sent to only one node Level-2 stream cont...
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- Spring '08
- Sensor node, Packet forwarding, Sink