當今使用者處於一個充滿了各種變數、可能會跨越過不同型態的網路環境下，要如何確保一個端點對端點間的服務品質是一個很大的議題，尤其特別是使用者在無線網路上執行換手動作時，必須花費時間重新建立或協商，而網路所提供使用者的資源更可能產生變動，對於要繼續維持使用者原本服務品質需求的服務是一大問題。
當使用者在透過接取網路連上IMS使用服務而需要換手時，在連結上新的接取網路而認證授權後，使用者還無法直接繼續使用IMS上的服務，還需經過IMS的認證授權和QoS保留資源後，才可以繼續先前的服務，因而等待過久的時間，對於IMS大多都是及時的服務影響很大，所以我提出一個作法，是藉由MIH的MIIS Server先得到PDF與P-CSCF的位址，提前傳送IMS所需的授權和QoS資訊，與接取網路的認證授權同時處理，減少換手所需等待的時間。
本文所提出來的方法較傳統的換手方式，不管是在換手次數、被dropping的機率，都有較佳的結果。

How to maintain an end-to-end QoS is a critical issue when the user is in the heterogeneous network environment. It needs time to rebuild or re-negotiate the user QoS profile when the mobile user hands over in the wireless networks. Because network resources may change by time, it’s hard to maintain users’ QoS demands.
As user being through IMS using IMS Services and need to handover service network. After authentication and authorization success, user connect with new access network but still unable to continue using the service on IMS. It needs to delay the authentication and authorization of IMS and keeps resource reservation with QoS. They can just continue the previous service. Therefore they has waited for long time. It’so influential that IMS is mostly all prompt services. So we propose an adaptive end-to-end QoS procedure where the address getting PDF & P-CSCF first with MIIS Server of MIH. Advance finishes inserting IMS authorization and QoS procedure of IMS, which can deal with accessing the authentication and authorization network at the same time, reducing the handover waiting time.
The results of our simulation show that the proposed mechanism is better both in handover times and dropping rate than old handover procedure.

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