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# 数学代写|密码学代写Cryptography代考|COMSW4261 Herbert O. Yardley

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## 数学代写|密码学代写CRYPTOGRAPHY代考|Herbert O. Yardley

We now come to perhaps the most colorful figure in the cryptologic world. Herbert $\mathrm{O}$. Yardley (Figure 5.4) could be called the Han Solo of cryptology. He’s often described as a gambler, a drinker, and a womanizer, and debate is still ongoing concerning his loyalty to the United States. Although both did important cryptanalytic work for the United States, Yardley and Friedman strike a strong contrast in almost every category. Friedman was very neat, dapper even. Yardley was often scruffy and would sometimes water the lawn in his underwear. At the time of his death he didn’t own a tie; one was given to his widow for Yardley to be buried in. ${ }^{18}$ Yardley was anti-Semitic, whereas Friedman was Jewish. ${ }^{19}$ Friedman had a long, apparently happy marriage, but one gets the impression that he didn’t have a great deal of confidence with women. Yardley, on the other hand, was not at all shy. He even bragged about knowing his way around a Chinese whorehouse and hosted orgies for visiting journalists and diplomats while he was in China. ${ }^{20}$ Although it’s not often a good indicator, even their handwriting represents their distinct personalities (Figures $5.5$ and 5.6).

Yardley started out in a noncryptographic position at the State Department; he was just a telegraph operator and code clerk, but having access to coded messages, including ones addressed to President Wilson, he made attempts to break them. He eventually produced a report “Solution of American Diplomatic Codes” for his boss. His successes made a strong case for the need for an improved American cryptographic bureau, or black chamber, and his skills at self-promotion catapulted him into a new position as chief of this new organization under the War Department, formally called the Cipher Bureau, in 1917. Black chambers had played an important role in European history, but such cryptanalytic units were new in the United States. In 18 months, Yardley’s team (Military Intelligence Section 8 , or MI-8) had read almost 11,000 messages in 579 cryptographic systems. This is even more amazing when one considers that the team initially consisted of only Yardley himself and two clerks. At its peak in November 1918, the team consisted of 18 officers, 24 civilians, and 109 typists. ${ }^{21}$

Of course, protecting America’s messages was also an important aspect of Yardley’s organization. Messages traveling to and from Europe via the transatlantic cable could be obtained by the Germans by having their submarines place long cables (bundreds of feet long) next to the transatlantic cable to pick up the messages by induction. Yardley’s team overhauled our codes and ciphers so that such interceptions wouldn’t matter. Yardley lamented the results of the Germans reading our World War I communications prior to this overhaul:
The American offensive of September 12, 1918, was considered a triumph, but it represents only a small part of what might have been a tremendous story in the annals of warfare, had the Germans not been forewarned. The stubborn trust placed in inadequate code and cipher systems had taken its toll at the Front. ${ }^{22}$

## 数学代写|密码学代写CRYPTOGRAPHY代考|Peacetime Victory and a Tell-All Book

Yardley’s peacetime Cipher Bureau relocated to New York. ${ }^{27}$ His first mission was to break the ciphers of the Japanese, even though he didn’t know Japanese. Despite this obstacle, the mission was successful. Yardley labeled the first Japanese code he broke in 1919 as Ja. J stood for Japan and the a acted like a subscript. As new Japanese codes came into being, and were broken, Yardley named them Jb, Jc, etc.

On November 12, 1921, the Washington Disarmament Conference began with the aim of settling disputes in the Far East. One issue was the tonnage ratios for the American, British, and Japanese navies. The United States favored a ratio of 10:10:6 for The United States, Britain, and Japan, respectively. That is, the Americans and Brits could have equal tonnage, but the Japanese Navy could not exceed 60\% of that figure. The Japanese favored a 10:10:7 ratio. The messages between the negotiators and their bosses were encoded with what Yardley termed Jp. The most important message sent in this system is reproduced below, as Yardley’s team decoded it. ${ }^{28}$
From Tokio
To Washington.
Conference No. 13. November 28, 1921 .
SECRET.
Referring to your conference cablegram No. 74, we are of your opinion that it is necessary to avoid any clash with Great Britain and America, particularly America, in regard to the armament limitation question. You will to the utmost maintain a middle attitude and redouble your efforts to carry out our policy. In case of inevitable necessity you will work to establish your second proposal of 10 to $6.5$. If, in spite of your utmost efforts, back on your proposal No. 3, you will endeavor to limit the power of concentration and maneuver of the Pacific by a guarantee to reduce or at least to maintain the status quo of Pacific defenses and to make an adequate reservation which will make clear that [this is] our intention in agreeing to a 10 to 6 ratio.
No. 4 is to be avoided as far as possible.

. byley

## 数学代写|密码学代写CRYPTOGRAPHY代考|和平时期的胜利和一本坦白一切的书

1921年11月12日，华盛顿裁军会议开始，目的是解决远东地区的争端。一个问题是美国、英国和日本海军的吨位比率。美国赞成美国、英国、日本的比率分别为10:10:6。也就是说，美国和英国可以拥有同等的吨位，但日本海军不能超过这个数字的60％。日本人喜欢10:10:7的比例。谈判代表和老板之间的信息用亚德利称之为Jp的编码。这个系统发送的最重要的信息如下所示，亚德利的团队对其进行了解码。${ }^{28}$

## MATLAB代写

MATLAB 是一种用于技术计算的高性能语言。它将计算、可视化和编程集成在一个易于使用的环境中，其中问题和解决方案以熟悉的数学符号表示。典型用途包括：数学和计算算法开发建模、仿真和原型制作数据分析、探索和可视化科学和工程图形应用程序开发，包括图形用户界面构建MATLAB 是一个交互式系统，其基本数据元素是一个不需要维度的数组。这使您可以解决许多技术计算问题，尤其是那些具有矩阵和向量公式的问题，而只需用 C 或 Fortran 等标量非交互式语言编写程序所需的时间的一小部分。MATLAB 名称代表矩阵实验室。MATLAB 最初的编写目的是提供对由 LINPACK 和 EISPACK 项目开发的矩阵软件的轻松访问，这两个项目共同代表了矩阵计算软件的最新技术。MATLAB 经过多年的发展，得到了许多用户的投入。在大学环境中，它是数学、工程和科学入门和高级课程的标准教学工具。在工业领域，MATLAB 是高效研究、开发和分析的首选工具。MATLAB 具有一系列称为工具箱的特定于应用程序的解决方案。对于大多数 MATLAB 用户来说非常重要，工具箱允许您学习应用专业技术。工具箱是 MATLAB 函数（M 文件）的综合集合，可扩展 MATLAB 环境以解决特定类别的问题。可用工具箱的领域包括信号处理、控制系统、神经网络、模糊逻辑、小波、仿真等。