隨著網際網路的快速發展，以主機為中心的IP 網路架構已經不能滿足當今對網路的需求。因此，以內容為中心的網路(CCN)出現進而取代傳統的IP 網路。因為未決興趣表(PIT)對於CCN 網路的效能具有重大的影響，我們的研究針對植基在細胞式網路的PIT 效能評估。在本篇研究中，我們分別考慮了四種PIT 佔用情境:只有一種新抵達到細胞中的興趣封包但不具重傳機制、只有一種新抵達到細胞中的興趣封包但具重傳機制、有新抵達或是交遞到細胞的興趣封包但不具重傳機制、有新抵達和交遞到細胞興趣封包但具重傳機制。在不論是否具有重傳機制但只有新抵達興趣封包的情境中，我們著重在研究只有一個單一細胞，或是所有節點皆是靜止的情形，且因此只有一種可能抵達的封包: 新抵達的興趣封包。而在不具重傳機制的情境下，如果PIT 中所有的條目都被佔用，新抵達到細胞的興趣封包會立刻被迫離開系統。然而在具重傳的機制情境下，新抵達的興趣封包可能會進入重傳佇列且稍後再嘗試尋找PIT 中空閒的條目。而在不論是否具有重傳機制但不只有新抵達的細胞還有交遞到此細胞的興趣封包的情境中，我們著重在研究有多個細胞且所有節點都是動態的情形，且因此有兩種可能抵達的封包:新抵達的興趣封包或是交遞到此細胞的興趣封包。首先，我們推導所考慮系統的解析模型。我們利用疊代演算法來求得穩態機率分布，且計算感興趣的效能指標。系統參數包含興趣抵達速率、興趣服務速率、興趣逾時時間、興趣聚合機率、興趣交遞速率、與興趣重傳速率。我們感興趣的效能指標是興趣阻塞機率、平均興趣系統延遲、平均興趣封包數、成功送達率、未完成率。第二，我們也比較了具有重傳機制與不具有重傳機制之間的差異性，還有在多個細胞中跟單一細胞之間的不同之處。第三，我們發現，在成功送達率與未完成率方面，具重傳機制的效能會勝過不具重傳機制的效能，但重傳機制會導致平均系統延遲及阻塞機率的增加。最後但非最不重要，在大部分情形下解析結果與模擬結果是很接近的。

With the rapid development of Internet, the host-to-host IP Internet architectures cannot satisfy the requirement of Internet. Therefore, the content-centric networking (CCN) emerges to replace the traditional IP networking. Because the pending interest table (PIT) has a significant effect on the performance of the CCN network, we focus on the research on performance evaluation of the PIT built on the cellular network. In this work, we study the four scenarios for PIT occupancy: new interest without retrial, new interest with retrial, new and handoff interest without retrial, new and handoff interest with retrial. In new interest without retrial or with retrial scenarios, we focus on the cases where there is a single cell or all nodes are stationary and thus there are only
one class of arrivals: new interest. In the scenarios without retrial, if all entries are
occupied, an arriving interest is cleared from the system immediately whereas in the scenarios with retrial, an arriving interest may enter into a retrial queue and retry to find an idle entry later. In new and handoff interest without retrial or with retrial scenarios, we focus on the cases where there are multiple cells and all nodes are mobile and thus there are two classes of arrivals: new interest and handoff interest. First, we derived the analytical models for the system considered. An iterative algorithm is developed to find the steady state probability distribution and the performance measures of interest. The system parameters include interest arrival rate, interest service rate, interest timeout time, interest aggregation probability, interest impatient rate, interest dwell rate, interest retrial rate, and interest retrial probability. The performance measures of interest are interest blocking probability, average number in service, average system delay,throughput, and incomplete rate. Second, for comparison, we study the performance with retrial and without retrial and the difference between the cases in a single cell or multiple cells. Third, it is shown that performance with retrial outperforms that without retrial in terms of the throughput and the incomplete rate at the expense of the average system delay and blocking probabilities. Last but not least, in most cases studied the analytical results are shown to be in good agreement with the simulation results.

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