问题 名词解释

《诸蕃志》

答案

参考答案:

宋代海外地理名著。作者赵汝适,成书于宋理宗宝庆元年(1225),分上、下两卷。记载了东自日本、西至东非索马里、北非摩洛哥及地中海东岸诸国的风土物产及自中国沿海至海外各国的航线里程及所达航期。其中虽然不免有错讹,但就全书史料价值来说,仍不失为记述古代中外交通的佳作,并经常为后来的史地学家所引用。原书久已佚亡。

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Typically, these are concern with the establishment of (66) the network and with the control of the flow of messages across this channel. The provision of such facilities is only part of the network requirements, however, since in many applications the communicating computers may be of different types. This means that they may use different programming languages and, more importantly, different forms of (67) interface between user(application)program, normally referred to, as application processes or APs, and the underlying communication services may be (68) For example, one computer may be a small single -user computer, while another may be a large (69) system. In the earlier days of computer communication, these issues meantthat only closed communities of computers ( that is, from the same manufacturer) could communicate with each other in a meaningful way. IBM’s Systems Network.
Architecture (SNA) and DEC’s Digital Network Architecture (DNA) are just two examples of Communication software packages produced by manufacturers to allow their systems to be int erconnected together. These proprietary packages, however, of which there am still many inexistence, do not address the problem of universal interconnect ability, or open systems interconnection. In an attempt to alleviate this problem, (70) , in the late 1970s, formulated a reference model to provide a common basis ( or the coordination of standards developments and to allow existing and evolving standards activities to beplaced into perspective with one another.

A. communication channel access B. protocols
C. data channel D. public communication