Internetworking with TCP/IP I-II. [antikvár]

Foreword This second edition of Professor Douglas Comer's book provides an up-to-date overview and introduction to TCP/IP. There have been many requests for the article, report, or book to read to get started on understanding the TCP/IP protocols. This book satisfies those requests. Writing an introduction to TCP/IP for the uninitiated is a very difficult task. While combining the explanation of the general principles of computer communication with the specific examples from the TCP/IP protocol suite, Doug Comer has provided a very readable book. While this book is specifically about the TCP/IP protocol suite, it is a good book for learning about computer communications protocols in general. The principles of architecture, layering, multiplexing, encapsulation, addressing and address mapping, routing, and naming are quite similar in any protocol suite, though, of course, different in detail (See Chapters 3, 10, 18, 20, and 26). Computer communication protocols do not do anything themselves. Like operating systems, they are in the service of application processes. Processes are the active elements that request communication and are the ultimate senders and receivers of the data transmitted. The various layers of protocols are like the various layers in a computer operating system, especially the file system. Understanding protocol architecture is like understanding operating system architecture. In this book Doug Comer has taken the "bottom up" approach - starting with the physical networks and moving up in levels of abstraction to the applications. Since application processes are the active elements using the communication supported by the protocols, TCP/IP is an "interprocess communication" (IPC) mechanism. While there are several experiments in progress with operating system style message passing and procedure call types of IPC based on IP, the focus in this book is on more traditional applications that use the UDP datagram or TCP logical connection forms of IPC (See Chapters 11, 12, 18, 20, and 22-25). Typically in operating systems there is a set of functions provided by the operating system to the application processes. This system call interface usually includes calls for opening, reading, writing, and closing files, among other things. In many systems there are similar system calls for IPC functions including network communication. As an example of such an interface Doug Comer presents an overview of the socket interface (See Chapter 21). One of the key ideas inherent in TCP/IP and in the title of this book is "internetworking." The power of a communication system is directly related to the number of entities in that system. The telephone network is very useful because (nearly) all the telephones are in one network (as it appears to the users). Computer communication