隨著社群多媒體以及行動裝置 (智慧型手機、平板) 的迅速發展，一般性行動社群網路 (GMSNs) 已經發展為兩層的社群網路。在短暫性社群網路 (Delay-Tolerant Networks 容遲網路) 中已經有許多有效率的資料轉發方法，但在雙層的GMSNs上只有少數方法。在這篇論文中，我們提出了一個結合短暫性社群(Delay-Tolerant Networks)以及社會關係(Online Social Networks)的資料轉發方式稱作Double Bubble。和其他文獻不同的是，Double Bubble 不僅在雙層之間做資料傳送也在兩層間做資訊交換。在雙層社群網路下的社群資訊交換對於資料轉發造成加乘的效果。除此之外，我們更提出了第二種用來幫助離群者接收到訊息的附加方法。在此，我們利用四個真實世界行走軌跡搭配四種不同的資料轉發方法進行模擬。在一般的資料轉發效能評估外，我們也對資訊量的交換成本做了測量。

By the rapidly increasing of social media and mobile devices (smart phone, tablet), the Generalized Mobile Social Network is extended to two-tier social networks. There are many efficient data forwarding schemes in transient community networks (Delay-Tolerant Networks), but there aren't many data forwarding schemes in two-tier GMSNs. In this paper, we proposed a two-tier GMSNs data forwarding scheme which combined Transient Community (Delay-Tolerant Networks) and Social Relationship (Online Social Networks), called Double Bubble. Different from other literature, Double Bubble does data transmission and information exchange in both two tiers. The two-tier social information exchange makes the synergy effect on data forwarding. Moreover, our second method is affiliated with a new idea which helps lonely people receiving messages.
In this paper, we do the simulation on four real-world traces with four data forwarding strategy, and we also do signal exchange measurement in addition to typical performance metrics in data forwarding.

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