tailieunhanh - Networking and Network Programming 2 TCP/IP phần 2

Nó viết một bài luận nói cho bạn có lẽ với một chút giọng Thụy Điển-những gì đang xảy ra như truy vấn được xử lý. Dưới đây là một số biểu thức thông thường nó có thể sử dụng:Ngay sau khi một cuộc gọi WinSock API không, bạn nên gọi Khái niệm cơ bản của WinSock lập trình | Chapter 2 TCP IP Overview simplest being a plain ASCII file where each line of the file has the IP address in dotted decimal notation to the left and the textual name to the right. This file is customarily named hosts and is referred to as the host file. The host file implementation is fine for a small network with relatively few computers but the management of such a file becomes unwieldy or impossible as the network grows to thousands of hosts as in the Internet or any large corporate network. In this environment a name server is utilized. A name server is a computer that provides a name to IP address resolution. When a request to translate a certain name to its IP address arrives at the name server it does a database lookup to see if it has this information. If not the request is passed on to an authoritative server. Authoritative servers are maintained with official data provided by the group responsible for the assignment of IP addresses. Subnetting Subnetting is a method of locally modifying the use of the network and hosts bits. By moving the dividing line that separates the host id part from the network id part more networks can be created at the same time the maximum number of hosts on each network is reduced. A subnet mask is used to define the new dividing line. It s represented in dotted decimal notation in much the same way as an IP address is. The bits that are set to one represent the network portion the remaining bits that are set to zero represent the host portion. Earlier I determined that the IP address of my computer resided on network and had a host id of . Officially speaking this is correct. But as it turns out the network administrators at my site have decided to use a network mask of to logically partition the address space into more networks. Looking at the logical view my network id is and my host id is 139. Another way of saying this is my computer is host 139 on subnet . Notice that the low .