基于SDRAM的精確查找方法研究與設(shè)計
發(fā)布時間：2019-05-17 23:19
【摘要】：隨著網(wǎng)絡(luò)技術(shù)的高速發(fā)展,互聯(lián)網(wǎng)已經(jīng)成為人們生活中不可或缺的部分。網(wǎng)絡(luò)業(yè)務(wù)流量呈每六個月倍增的趨勢。隨著光通信技術(shù)的發(fā)展,鏈路傳輸速率已不再是網(wǎng)絡(luò)技術(shù)的性能瓶頸,而網(wǎng)絡(luò)查找轉(zhuǎn)發(fā)處理則成了制約互聯(lián)網(wǎng)發(fā)展的關(guān)鍵因素之一。針對現(xiàn)有網(wǎng)絡(luò)管理不靈活、流量調(diào)度不均勻的問題,軟件定義網(wǎng)絡(luò)(Soft-Defined Network,SDN)的概念被提出來。在SDN的核心協(xié)議OpenFlow中,查找以流表的形式存在。本文利用片外存儲器設(shè)計查找表,重點研究了適合OpenFlow交換機的精確查找方法。 本論文首先對現(xiàn)有的高速查找方法進(jìn)行了調(diào)研和分析。結(jié)合基于前綴的路由查找方法和OpenFlow交換機中流表的形式,提出了一種基于SDRAM(Synchronous Dynamic Random Access Memory)的精確查找方法。該方法主要包括硬件預(yù)處理和片外查找表兩個方面。在硬件預(yù)處理方面,提出了基于并行布隆過濾器的硬件預(yù)處理方法,用于減少一次成功查找所需要片外存儲器的訪問次數(shù)。經(jīng)過片內(nèi)資源的合理分配和布隆過濾器的改進(jìn),最終一次成功查找所需要的片外訪問的次數(shù)近似為一次。然后,結(jié)合OpenFlow中流表需要具備可擴展性和并行查找的需求,論文提出了一種容量可配置的并行布隆過濾器,最后為了降低片內(nèi)處理的功耗,提出了一種兩級流水線型的布隆過濾器,當(dāng)配置合適時,最多可以節(jié)省80%的功耗。在片外查找表方面,本文研究了片外存儲器SDRAM指令重排機制,以提高片外緩存的總線利用率。本文提出的基于突發(fā)交錯的指令重排機制與現(xiàn)有的突發(fā)調(diào)度重排機制相比總線利用率提高了25%。然后本文根據(jù)OpenFlow流表的形式和SDRAM器件特性設(shè)計了適合流表查找的SDRAM地址分配方案。最后本文研究了SDRAM的控制原理和SDRAM控制器的設(shè)計方法,并利用FPGA實現(xiàn)了SDRAM控制器 OpenFlow交換機中流表的查找形式有利于更靈活地控制網(wǎng)絡(luò),但是多流表查找也對高速查找算法提出了更高的要求,所以對適用于OpenFLow流表查找算法的研究具有重要的意義。
[Abstract]:With the rapid development of network technology, the Internet has become an indispensable part of people's lives. Network traffic shows a trend of doubling every six months. With the development of optical communication technology, link transmission rate is no longer the performance bottleneck of network technology, and network search and forwarding processing has become one of the key factors restricting the development of the Internet. In order to solve the problems of inflexible network management and uneven traffic scheduling, the concept of software defined network (Soft-Defined Network,SDN) is put forward. In OpenFlow, the core protocol of SDN, search exists in the form of flow table. In this paper, the off-chip memory is used to design the lookup table, and the accurate search method suitable for OpenFlow switch is studied. In this paper, the existing high-speed search methods are investigated and analyzed. Based on the prefix based routing lookup method and the form of flow table in OpenFlow switch, an accurate search method based on SDRAM (Synchronous Dynamic Random Access Memory) is proposed. This method mainly includes two aspects: hardware preprocessing and off-chip look-up table. In the aspect of hardware preprocessing, a hardware preprocessing method based on parallel Bron filter is proposed to reduce the number of visits to the off-chip memory needed for a successful search. After the reasonable allocation of on-chip resources and the improvement of Bron filter, the number of off-chip visits required for a successful search is approximately one. Then, in order to reduce the power consumption of on-chip processing, a parallel Bron filter with configurable capacity is proposed to meet the needs of scalability and parallel search of flow table in OpenFlow. A two-stage streamline Bron filter is proposed, which can save up to 80% power consumption when it is properly configured. In the aspect of off-chip look-up table, this paper studies the SDRAM instruction rearrangement mechanism of off-chip memory in order to improve the bus utilization of off-chip cache. Compared with the existing burst scheduling rearrangement mechanism, the bus utilization of the instruction rearrangement mechanism based on burst interleaving proposed in this paper is 25% higher than that of the existing burst scheduling rearrangement mechanism. Then, according to the form of OpenFlow flow table and the characteristics of SDRAM device, a SDRAM address assignment scheme suitable for stream table search is designed in this paper. Finally, this paper studies the control principle of SDRAM and the design method of SDRAM controller, and uses FPGA to realize the look-up form of flow table in SDRAM controller OpenFlow switch, which is beneficial to more flexible control network. However, multi-stream table search also puts forward higher requirements for high-speed search algorithm, so it is of great significance to study the algorithm suitable for OpenFLow flow table search.
【學(xué)位授予單位】：北京郵電大學(xué)
【學(xué)位級別】：碩士
【學(xué)位授予年份】：2014
【分類號】：TP393.07
本文編號：2479485
[Abstract]:With the rapid development of network technology, the Internet has become an indispensable part of people's lives. Network traffic shows a trend of doubling every six months. With the development of optical communication technology, link transmission rate is no longer the performance bottleneck of network technology, and network search and forwarding processing has become one of the key factors restricting the development of the Internet. In order to solve the problems of inflexible network management and uneven traffic scheduling, the concept of software defined network (Soft-Defined Network,SDN) is put forward. In OpenFlow, the core protocol of SDN, search exists in the form of flow table. In this paper, the off-chip memory is used to design the lookup table, and the accurate search method suitable for OpenFlow switch is studied. In this paper, the existing high-speed search methods are investigated and analyzed. Based on the prefix based routing lookup method and the form of flow table in OpenFlow switch, an accurate search method based on SDRAM (Synchronous Dynamic Random Access Memory) is proposed. This method mainly includes two aspects: hardware preprocessing and off-chip look-up table. In the aspect of hardware preprocessing, a hardware preprocessing method based on parallel Bron filter is proposed to reduce the number of visits to the off-chip memory needed for a successful search. After the reasonable allocation of on-chip resources and the improvement of Bron filter, the number of off-chip visits required for a successful search is approximately one. Then, in order to reduce the power consumption of on-chip processing, a parallel Bron filter with configurable capacity is proposed to meet the needs of scalability and parallel search of flow table in OpenFlow. A two-stage streamline Bron filter is proposed, which can save up to 80% power consumption when it is properly configured. In the aspect of off-chip look-up table, this paper studies the SDRAM instruction rearrangement mechanism of off-chip memory in order to improve the bus utilization of off-chip cache. Compared with the existing burst scheduling rearrangement mechanism, the bus utilization of the instruction rearrangement mechanism based on burst interleaving proposed in this paper is 25% higher than that of the existing burst scheduling rearrangement mechanism. Then, according to the form of OpenFlow flow table and the characteristics of SDRAM device, a SDRAM address assignment scheme suitable for stream table search is designed in this paper. Finally, this paper studies the control principle of SDRAM and the design method of SDRAM controller, and uses FPGA to realize the look-up form of flow table in SDRAM controller OpenFlow switch, which is beneficial to more flexible control network. However, multi-stream table search also puts forward higher requirements for high-speed search algorithm, so it is of great significance to study the algorithm suitable for OpenFLow flow table search.
【學(xué)位授予單位】：北京郵電大學(xué)
【學(xué)位級別】：碩士
【學(xué)位授予年份】：2014
【分類號】：TP393.07
【參考文獻(xiàn)】
相關(guān)期刊論文 前3條
1 李振強;鄭東去;馬嚴(yán);;TSB:一種多階段IPv6路由表查找算法[J];電子學(xué)報;2007年10期
2 胥小波;鄭康鋒;李丹;楊義先;鈕心忻;;基于并行BP神經(jīng)網(wǎng)絡(luò)的路由查找算法[J];通信學(xué)報;2012年02期
3 崔宇;田志宏;張宏莉;方濱興;;基于前綴區(qū)間集合的IPv6路由查找算法[J];通信學(xué)報;2013年06期
相關(guān)博士學(xué)位論文 前1條
1 孫瓊;下一代互聯(lián)網(wǎng)的報文標(biāo)識與查找技術(shù)的研究[D];北京郵電大學(xué);2010年
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