在無線機會網路下，網絡中的節點具有移動性並且透過無線感應來傳輸訊息，因此節點與節點之間並不存在一條始終保持連線的通道，進而形成破碎的網路拓樸。然而在這類的耐延遲網路中已有許多相關研究，其特殊的傳遞訊息方式— store-carry-and-forward，藉由節點機會性的相遇方式來傳遞訊息，因此對傳輸效能有極大的限制與影響。為了改善現有方法的傳輸效能，在這篇論文中，我們提出一個新的路由策略— 基於時間週期性之訊息傳送機制(TPMD)。TPMD 是一個基於週期特性所設計之路由策略，主要著重在節點的移動週期之紀錄、與過去不同的週期定義以及量化週期特性。後續的模擬中證明了TPMD 對於傳送效能有顯著的改善，即使是在條件較差的網路環境：節點的暫存空間小、訊息存活時間長。

Wireless opportunistic networks represent mobile wireless networks that are generally characterized by broken topology, no end-to-end paths from a source to a destination. Although routing algorithms in this kind of Delay-tolerant networks (DTNs) are being increasingly designed, the network performance associated with store-carryand-forward is still limited because of opportunistic contacts. In this thesis, we propose a routing scheme in DTNs, named Temporal Periodicity for Message Delivery method (TPMD), for achieving greater performance than exist routing protocols. TPMD is a periodic routing, which focus on the characteristic of periodicity about movement, adjustment of common period definition and period quantification procedure, as a result of significance of temporal periodicity in DTNs. Finally, substantial simulations show that the TPMD can effectively improve network performance under a constrained environment with limited buffer size and prolonged TTL of messages in a network.

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