HTTP报文的深层定位抽取在高速七层交换技术中的设计与实现
日期:2018年01月15日
编辑:
作者:无忧论文网
点击次数:1956
论文价格:150元/篇
论文编号:lw200705272139307710
论文字数:23257
所属栏目:计算机网络论文
论文地区:
论文语种:中文
论文用途:硕士毕业论文 Master Thesis
摘 要
随着网络带宽的进一步提高和网络技术的进一步发展,网络交换技术已经不仅仅局限于解决局域网和互联网络的带宽及容量问题,更需要提供更高的可用性、负载均衡以及智能化的服务,第七层交换技术由于能实现对所有传输流和内容的控制,因此可以提供大大优于第四层交换的智能性和可用性,因此在现在日益重视网络服务质量的环境中大有用武之地。在所有这些基于内容的服务中都需要在报文中寻找及抽取某些预先确定的字段,而基于软件算法的实现方案无法满足高速网络的速度需求,因此需要一种基于硬件实现并具有良好的可扩展性的解决方案。
本文首先介绍了七层交换的相关原理及关键技术,分析了数据报文深层定位与抽取技术的重要性,并详细讨论了软件实现的报文深层定位抽取实现方案,并分析了其在高速交换中的性能弱点,指出了硬件实现数据报文深层定位抽取的必要性和艰巨性。在此基础上,本文提出了一种基于ASIC实现的HTTP报文深层定位抽取引擎的解决方案,并详细讨论其中的URL解析抽取模块和基于矩阵开关设计的模式匹配模块的设计与实现。
本文最后给出了一种基于ATPG的ASIC前端验证解决方案,分析了这种方案的原理和流程,然后对这种方案在数据报文深层定位抽取引擎测试中的使用做了详细的讨论并给出了具体的测试方案。经过Verilog的RTL级实现,此方案达到了预期目标,并具有良好的可扩展性和很好的可配置性,同时其实现为可配置高速交换的硬件设计具有较大的参考和借鉴意义。
关键词: 七层交换,数据报文深层定位抽取,模式匹配,HTTP,URL,ASIC
Abstract
As the rapid development of communication techniques, the network needs to provide high usability, load-balancing and intelligibility functions such as content-based billing, layer-7 switching and Internet security services. Recent advances in network packet processing focus on payload inspection for applications. Most of these applications in this family need to search for predefined signatures in the packet payload. Hence an important building block of these processors is string matching infrastructure. Since conventional software-based algorithms for string matching have not kept pace with high network speeds, specialized high-speed, hardware-based solutions are needed.
The thesis firstly evaluates and analyzes the background of the high-level switching, the importance of deep packet parsing and extraction technique, the software design and implementation of content-based switching. Then bring out the essentiality of hardware-based solution. We bring forward a solution scheme for deep HTTP packets parsing and extractions, and provide the design and implementation of URL P&E module and the pattern match module.
Finally, the thesis brings forward a building scheme of atpg-based ASIC verification environment, provides the test scheme of this HTTP deep P&E engine. The design and implementation scheme is provided with advisable reference significance.
Key Words: layer-7 switching, Deep packet Parsing and Extraction,
Pattern match, HTTP, URL, ASIC