WiFi卸載(WiFi offloading)技術透過將部分資料流量交給WiFi網路處理，以減輕基地台的負擔，其中IETF在2013年提出透過MPTCP協定，讓我們可以同時透過行動網路與WiFi兩種網路介面收送資料。然而，有些連上WiFi的User Equipment(UE)並不總是需要這麼多的頻寬，因此有了WiFi連線後，他們的部分行動網路頻寬是可以拿出來分享的，本篇論文探討如何分配這些頻寬以提升使用者的總體滿足度，進而提升Operator的獲利。本篇論文提出了SDBR與SDBR-R兩種機制。SDBR專注於降低Blocking Probability，進而提升總體的滿足度(Sum Satisfaction)。SDBR-R則提供了頻寬還回的機制，希望能在提升總體滿足度的同時，也提升個別滿足度(Per User Satisfaction)。我們使用檔案下載來對兩個演算法進行模擬，並與其他現有的演算法做比較。模擬的結果顯示SDBR降低了Blocking probability，並提高了總體Satisfaction。而SDBR-R的總體滿足度雖然比SDBR低，但個人滿足度卻比SDBR還要高。

IETF have proposed a Multipath TCP (MPTCP) standard at 2013, which allows User Equipment(UE) connect to several network interface simultaneously. However, not all of the user with WiFi connection exactly need so much bandwidth. So we can share some of cellular bandwidth form the UE with WiFi connection to another. In this paper, we proposed SDBR and SDBR-R mechanism to utilize the sharing bandwidth. Aiming to enhance total satisfaction from all user, which is correlate to operator’s total revenue. SDBR aim to serve more user by reducing blocking probability. While SDBR-R aim to provide good per-user satisfaction while improving total satisfaction. In the numerical result, SDBR successfully improve the total user satisfaction, and its blocking probability is reduced. Sum satisfaction of SDBR-R is the second, but its per user satisfaction is better than SDBR.

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