為了確立伺服器和客戶端之間的角色,因此我們提出集中式的最小 k-支配集 合的自我穩定演算法。進一步為了讓每個節點有自己不同的支配需求,而延伸出 最小多支配集合的問題,而提出使用集中式模型的最小多支配集合自我穩定演算 法。如此一來只要由集合中的支配節點負責扮演伺服器的角色,不僅可以節省成 本,並且可增加整體網路的可靠度。
在實驗部份,我們模擬出傳統找最小支配集合的演算法及我們所提出的自我 穩定演算法、先前賽局的方法實作[17],並且實作出了四種拓樸邏輯(UDG、ER model、BA model、WS model),當作執行時的拓樸邏輯,如此一來即可在不同 方法之間做效能比較。實驗結果顯示,無論在何種拓樸邏輯中,k 為 1~5 時,我 們的方法所需的平均支配者個數都是最少的,代表我們的方法效能最好,但如果 k 再繼續增加,我們的方法的效果顯然較不明顯,而且要到達穩定的時間會更長,
是以時間來換取效能的方法。而其它方法在不同拓樸邏輯下,效果各有優缺點,
因此每個演算法其實會有較適合自己運作的拓樸邏輯。
未來可以把最小支配集合問題延伸為探討最大獨立集合的問題,來和[4],
[7],[8],[25] 做比較,差別在於希望集合中的節點越多越好。再來若能在網路 中找一條路徑把支配集合中的節點相連,形成網路的骨幹,即為連通的支配集合 (connected dominating set)[26],[27],[28],如此一來,若想把資料傳給網路中的 節點,我們只要傳給骨幹中的任一節點,它再廣播出去,其它接收到資料的支配 節點再廣播,就能確保網路中所有節點都能收到資料。最後若給予每個節點一個 權重值,之後找出支配集合,使得支配集合內的節點權重值總合越大或越小越 好,依不同需求來設計。由於還沒有人提出針對找最小多支配集合的方法,往後 若有人提出即可參考我們的方法做比較。
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