超级能吃的兔兔
是FTP 吧 什么是FTP呢?FTP 是 TCP/IP 协议组中的协议之一,是英文File Transfer Protocol的缩写。该协议是Internet文件传送的基础,它由一系列规格说明文档组成,目标是提高文件的共享性,提供非直接使用远程计算机,使存储介质对用户透明和可靠高效地传送数据。简单的说,FTP就是完成两台计算机之间的拷贝,从远程计算机拷贝文件至自己的计算机上,称之为“下载(download)”文件。若将文件从自己计算机中拷贝至远程计算机上,则称之为“上载(upload)”文件。在TCP/IP协议中,FTP标准命令TCP端口号为21,Port方式数据端口为20。FTP协议的任务是从一台计算机将文件传送到另一台计算机,它与这两台计算机所处的位置、联接的方式、甚至是是否使用相同的操作系统无关。假设两台计算机通过ftp协议对话,并且能访问Internet, 你可以用ftp命令来传输文件。每种操作系统使用上有某一些细微差别,但是每种协议基本的命令结构是相同的。 FTP的传输有两种方式:ASCII传输模式和二进制数据传输模式。 1.ASCII传输方式:假定用户正在拷贝的文件包含的简单ASCII码文本,如果在远程机器上运行的不是UNIX,当文件传输时ftp通常会自动地调整文件的内容以便于把文件解释成另外那台计算机存储文本文件的格式。 但是常常有这样的情况,用户正在传输的文件包含的不是文本文件,它们可能是程序,数据库,字处理文件或者压缩文件(尽管字处理文件包含的大部分是文本,其中也包含有指示页尺寸,字库等信息的非打印字符)。在拷贝任何非文本文件之前,用binary 命令告诉ftp逐字拷贝,不要对这些文件进行处理,这也是下面要讲的二进制传输。 2.二进制传输模式:在二进制传输中,保存文件的位序,以便原始和拷贝的是逐位一一对应的。即使目的地机器上包含位序列的文件是没意义的。例如,macintosh以二进制方式传送可执行文件到Windows系统,在对方系统上,此文件不能执行。 如果你在ASCII方式下传输二进制文件,即使不需要也仍会转译。这会使传输稍微变慢 ,也会损坏数据,使文件变得不能用。(在大多数计算机上,ASCII方式一般假设每一字符的第一有效位无意义,因为ASCII字符组合不使用它。如果你传输二进制文件,所有的位都是重要的。)如果你知道这两台机器是同样的,则二进制方式对文本文件和数据文件都是有效的。 5. FTP的工作方式 FTP支持两种模式,一种方式叫做Standard (也就是 PORT方式,主动方式),一种是 Passive (也就是PASV,被动方式)。 Standard模式 FTP的客户端发送 PORT 命令到FTP服务器。Passive模式FTP的客户端发送 PASV命令到 FTP Server。 下面介绍一个这两种方式的工作原理: Port模式FTP 客户端首先和FTP服务器的TCP 21端口建立连接,通过这个通道发送命令,客户端需要接收数据的时候在这个通道上发送PORT命令。 PORT命令包含了客户端用什么端口接收数据。在传送数据的时候,服务器端通过自己的TCP 20端口连接至客户端的指定端口发送数据。 FTP server必须和客户端建立一个新的连接用来传送数据。 Passive模式在建立控制通道的时候和Standard模式类似,但建立连接后发送的不是Port命令,而是Pasv命令。FTP服务器收到Pasv命令后,随机打开一个高端端口(端口号大于1024)并且通知客户端在这个端口上传送数据的请求,客户端连接FTP服务器此端口,然后FTP服务器将通过这个端口进行数据的传送,这个时候FTP server不再需要建立一个新的和客户端之间的连接。 很多防火墙在设置的时候都是不允许接受外部发起的连接的,所以许多位于防火墙后或内网的FTP服务器不支持PASV模式,因为客户端无法穿过防火墙打开FTP服务器的高端端口;而许多内网的客户端不能用PORT模式登陆FTP服务器,因为从服务器的TCP 20无法和内部网络的客户端建立一个新的连接,造成无法工作。
紫色super
1, on the economic growth essential for the accumulation of physical capital.2、 引进国外的先进设备和技术诀窍。 2, the introduction of foreign advanced equipment and technical know-how.3、 占世界技术贸易总量90%的许可证贸易。 3, accounting for 90% of total world trade, technology licensing trade.4、 经济发展中所反映出来的人力资本的匮乏。 4, economic development is reflected in the lack of human capital.5、 高科技对产业调整的重大影响。 5, high-tech major impact on industrial restructuring.6、 推动经济增长的关键因素。 6, a key factor in promoting economic growth.7、 从一个农业国向工业国的转型。 7, from an agricultural country to industrial countries in transition.8、 构成全要素生产率增长的有形和无形因素。 8, constitute the total factor productivity growth of tangible and intangible factors.9、 隐藏在技术进步之后的教育系统的改善。 9, after hiding in the technological progress to improve the education system.10、 该产业中资本与劳动力的比率。 10, the industry's ratio of capital and labor.11、 增长劳动力数量并提高其教育培训程度。 11, an increase of labor force and increase their level of education and training.12、 研发部门在跨国公司经营中的作用。 12, R & D departments in multinational companies operating in the role.13、 一份对多国技术进步情况进行分析的报告。 13, a multi-country situation analysis of technical progress report.14、 把计量和模型结合引入经济分析。 14, the combined measurement and model into economic analysis.15、 发达国家和发展中国家在收入上的巨大差距。 15 developed and developing countries the huge gap in income.二1、 不少经济学家认为,像香港、新加坡这样土地稀少的地区,其经济的快速发展应该主要归功于教育程度的提高。 2 1, many economists believe that, like Hong Kong, Singapore, this land is scarce in the region, its rapid economic development should be mainly attributed to the improvement of education. 在此基础上,经济学家们得出了结论:知识是这些国家或地区经济发展的主要因素。 On this basis, economists came to the conclusion: knowledge of these countries or regional economic development factors.2、 60年代,日本在从发达国家大量引进尖端技术和技术诀窍的基础上,进行了大规模的经济扩张活动,使日本的经济在短短的20年间迅速赶上了世界先进水平。 2, 60's, Japan imported from the developed countries, a large number of cutting-edge technology and technical know-how based on the economic expansion on a large scale activities, so that the Japanese economy in the short span of 20 years to catch up with the world advanced level quickly.3、 新经济理论的发展给统计学提出了许多课题,例如,高就学率并不意味着经济的高增长率,如果教育质量很差,或受过教育的人们在一个扭曲的劳动力市场上不能人尽其用的话。 3, the development of new economic theory to the statistics put forward a number of issues, such as high school attendance does not mean that high economic growth rate, if the quality of education is poor, or educated people in a distorted labor market, not people make the best use of it.4、 1944年,在经过长期研究之后,著名经济学家克鲁格曼发表了一份对多国技术进步情况调查的报告。 4, 1944, after long study, the well-known economist Paul Krugman published a multi-country survey of technological progress report. 他指出,亚洲的经济不是建立在技术进步的基础上,所以含有很多泡沫。 He pointed out that Asia's economy is not built on the basis of technological progress, it contains a lot of foam. 3年后爆发的东南亚经济危机证实了他的猜想。 3 years after the outbreak of the Southeast Asian economic crisis confirmed his guess.5、 由于科学技术在一定程度上是无形的,所以,到目前为止,人间还未想出确定其价值大小的理想方法 5, due to a certain extent, science and technology is invisible, so far, has not come up with to determine the value of human ideal way to size
xyrlovecat
1, on the economic growth essential for the accumulation of physical capital.2, the introduction of foreign advanced equipment and technical know-how.3, accounting for 90% of total world trade, technology licensing trade.4, economic development is reflected in the lack of human capital.5, high-tech major impact on industrial restructuring.6, a key factor in promoting economic growth.7, from an agricultural country to industrial countries in transition.8, constitute the total factor productivity growth of tangible and intangible factors.9, after hiding in the technological progress to improve the education system.10, the industry's ratio of capital and labor.11, an increase of labor force and increase their level of education and training.12, R & D departments in multinational companies operating in the role.13, a multi-country situation analysis of technical progress report.14, the combined measurement and model into economic analysis.15 developed and developing countries the huge gap in income.Two1, many economists believe that, like Hong Kong, land-scarce regions like Singapore, its rapid economic development should be mainly attributed to higher level of education. On this basis, economists came to the conclusion: knowledge of these countries or regional economic development factors.2, 60's, Japan imported from the developed countries, a large number of cutting-edge technology and technical know-how based on the economic expansion on a large scale activities, so that the Japanese economy in the short span of 20 years to catch up with the world advanced level quickly.3, the new economic theory of development has made many significant issues, for example, high student ratio does not mean that economic growth rates, if Jiaoyuzhiliang poor, or educated people in a Niuqu labor market can not Ren make the best use of it.4, 1944, after long study, the well-known economist Paul Krugman published a multi-country survey of technological progress report. He pointed out that Asia's economy is not built on the basis of technological progress, it contains a lot of foam. 3 years after the outbreak of the Southeast Asian economic crisis confirmed his guess.5, due to science and technology is invisible to some extent, so far, has not come up with to determine the value of human size ideal way
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