TCP/IP addressing

TCP/IP addressing 1. Each computer must have an IP address to connect to the Internet. Each IP package must have one address before it can be sent to another computer. 2. The IP address contains four numbers: 219.136.30. *** TCP/IP uses four numbers to address the computer. Each computer must have a unique 4-digit address. Numbers are between 0 and 255 and are separated by dots. For example, 192.168.1.60 3. TCP uses a fixed connection TCP for communications between applications. When an application wants to communicate with another application over TCP, it sends a Communication Request. This request must be sent to an exact address. After both parties "Shake hands", TCP will establish a full-duplex communication between the two applications. This full-duplex communication will occupy the communication line between two computers until it is closed by either or both parties. UDP is similar to TCP, but it is simpler, and the reliability is lower than TCP. 4. 32 bits = 4-byte TCP/IP uses 32 bits for addressing. The size of a computer is 8 bits. Therefore, TCP/IP uses 4 bytes. A computer byte can contain 256 different values: 00000000, 00000001, 00000010, 00000011, 00000100, 00000101, 00000110, 00000111 until 00001000. Now you know why the TCP/IP address is 4 numbers between 0 and 255. 5. The domain name contains 12 Arabic numerals which are hard to remember. It is easier to use a name. The TCP/IP address is called a domain name. W3school.com.cn is a domain name. When you type a domain name like a http://www.w3school.com.cn, the domain name is translated as a number by a DNS program. In the world, a large number of DNS servers are connected to the Internet. The DNS server is responsible for translating domain names into TCP/IP addresses and updating systems with new domain name information. When a new domain name is registered with its TCP/IP address, DNS servers around the world update this information.