近年來，在無線通訊中的無線感測網路(wireless sensor networks)快速崛起，無線感測網路是由一大群分散的感測節點(sensor node)所組成，這些感測節點透過資料收集和彙整，提供給使用者取得許多有效得資訊。在已經部署好的感測節點中，架構起網路組織，使得感測節點收集到的資訊能以消耗最少的感測器能量的方式，自感測節點回傳到使用者，是一項相當重要的研究議題之一。

在這篇論文中，我們提出一個階層式傳輸架構，以群體架構(group-based)為基礎來組織感測節點，藉由兩階段選舉來選出群體領導人(group-leader)，各群以此群體領導人當成代表來傳送資料。每當感測節點定期產生資料時，在這份資料從感測節點傳送到使用者的過程中，會透過一個分散式資料叢集模型來處理資料。資料處理的過程中，並不會影響這份資料對於使用者的可讀性。如此一來，除了可以達到一定程度負載平衡，在資料傳輸上也比較有效率，無線感測網路的生命週期也可因此而延長。

Sensor　network　is　an　emerging　area　of　wireless　networking　where　hundreds　or　even　thousands　of　unattended　sensors　runs　as　data　generator.　Sensor　nodes　can　coordinate　to　perform　distributed　sensing　of　environmental　phenomena.　Disseminating　data　generated　by　sensors　to　sinks　at　different　location　is　one　of　useful　function　of　wireless　sensor　networks　(WSN).　Recent　research　focus　much　on　how　does　a　source　forward　sensor　directly　to　the　sink.　As　sensors　have　limited　resource,　energy　consuming　in　interest　propagation　or　in　grid　maintenance　or　in　dissemination　tree　is　larger　than　that　in　sensor　data　transmission.　In　this　paper,　we　propose　novel　data　dissemination　architecture　with　hierarchical　data　aggregation　and　group　management.　Nodes　are　divided　into　logical　groups　by　holding　a　two-phase　leader　election.　All　nodes　can　complete　for　being　the　candidates　for　another　contest.　Leader　will　be　elected　among　these　candidates.　During　the　sensing　task,　sensor　nodes　periodically　generate　sensory　data,　and　these　data　will　be　processed　through　a　distributed　aggregation　way.　The　processed　data　is　sent　from　nodes　to　sinks　through　a　four-tier　data　forwarding　model.　This　architecture　can　be　generally　applied　to　other　sensor　systems,　where　communication　efficiency　is　a　paramount　concern　and　networking　resource　are　limited.

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