本文針對低功耗有損網路的網路壽命及延展性問題,提出一個可應變式路由 機制,考量三種網路情況(Network Condition),包括電量等級(Energy Level)、網 路收斂(Network Convergence)及傳輸流量(Traffic Load)情況,進行 Trickle Timer 參數的動態調整。(1)電量等級分成節點剩餘電量低於門檻值時,代表網路壽命時 間即將萎縮,為了延長低功耗有損網路壽命,本方法會進行參數的動態調整,讓 控制訊息發送的速度減緩,達到延展網路壽命的效果;(2)當網路收斂時,代表節 點已經找到路徑後網路拓樸已經呈現穩定狀況,為了減少不必要的控制訊息的浪 費,本系統會進行參數的動態調整,讓控制訊息發送的速度減緩,達到省電的效 果;(3)最後考量的網路情況為傳輸流量時,當傳輸流量(Traffic Load)為重負載
(Heavy)時,本機制會進行參數的動態調整,讓傳輸流量大的來源節點控制訊息發 送的速度減緩,達到延長網路壽命的效果。經由模擬實驗證明,本論文提出的可 應變式路由機制確實可以延長網路壽命及提供較佳的可延展性。
低功耗有損網路仍存在其他網路情況影響系統效能,未來將考量更多的網路 情況及應用需求,更進一步改善可應變式路由機制的效能。
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