TCP splicing是一種不了解使用者請求內容的第四層交換器技術，也就是說，第四層交換器無法使用應用層的資訊做封包轉送。在本文中，我們提出一個TCP splicing的延伸技術，稱為FPS，FPS使得TCP splicing得以使用應用層的資訊做負載平衡。在FPS中，一個使用者的連線將在FPS交換器與所有的後端伺服器之間預先建立連線；除此之外，FPS利用在核心層中擷取應用層的資訊以減少資料在使用者層與核心層之間的複製時間。我們從LVS中取得TCPSP並且修改TCPSP以實作FPS，而LVS則是利用Linux Netfilter實作。在叢集式的環境中，實驗存取動態網頁的結果顯示：FPS在產能與延遲時間方面分別比TCPSP優良四倍與五倍。

　　TCP splicing is a content-blind layer-4 switch technique that prevents the switches from using the application layer information for forwarding decisions. In this paper, we proposed a new technique called fully pre-splicing (FPS) which is an extension of TCP splicing. FPS extends TCP splicing to support content-aware load balancing algorithms. In FPS, one connection is pre-established between the FPS switch and each back-end server. In addition, FPS extracts the application information in kernel space for eliminating the cost of moving data between user and kernel spaces. We implemented the proposed FPS by modifying the TCPSP project of LVS using Linux Netfilter. The performance results show that the throughput and latency of accessing dynamic web pages in clustered web servers using FPS switch is four times and five times better than that using TCPSP, respectively.

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