Shulou(Shulou.com)06/02 Report--

This article is about several layers of hierarchical structure adopted by the tcp/ip protocol. The editor thinks it is very practical, so share it with you as a reference and follow the editor to have a look.

Tcp/ip protocol adopts a four-layer hierarchical structure: 1, network interface layer (host-network layer); 2, internetwork layer, providing simple, flexible, connectionless, best-effort Datagram services; 3, transport layer, providing end-to-end logical communication between application processes; 4, application layer, providing applications for users.

The operating environment of this tutorial: windows7 system, Dell G3 computer.

1. Network interface layer

In the TCP/IP protocol, the network interface layer is located in layer 4. Because the network interface layer merges the physical layer and the data link layer, the network interface layer is not only the physical medium for transmitting data, but also provides an accurate line for the network layer.

The physical layer defines some characteristics related to the interface of the transmission media, namely, mechanical properties, electrical characteristics, functional characteristics, and process characteristics, and needs to complete the conversion between parallel transmission and serial transmission.

The data link layer provides transparent and reliable data transmission services to users in this layer. Transparency means that there is no restriction on the content, format and coding of the data transmitted on this layer, and there is no need to explain the meaning of the information structure; reliability refers to transforming the error-free physical connection provided by the physical layer into a logically error-free data link in the process of transmission, and its specific methods include frame synchronization, error control, flow control and link management.

The main broadband access technologies in the physical layer are xdsl, hybrid fiber coaxial network (HFC) and FTTx technology.

The main protocols in the data link layer are point-to-point protocol PPP,CSMA/CD, Ethernet 802.3.

2. Internet layer

The Internet layer provides simple, flexible, connectionless, best-effort Datagram services up the value. The Internet layer does not provide the promise of quality of service, that is, the transmitted packets may be error, loss, repetition and disorder, and certainly does not guarantee the time limit for packet delivery.

The main protocols in the Internet layer are IP protocol, address resolution protocol ARP and inverse address resolution protocol RARP, and Internet control message protocol ICMP.

IP protocol is the core of the Internet layer. Through routing, the next hop IP is encapsulated and handed over to the network interface layer. IP Datagram is a connectionless service.

ICMP is a supplement to the Internet layer and can send back messages. Used to detect whether the network is open (using the ping command).

ARP looks for the MAC address of the host through a known IP.

RARP determines the IP address by the MAC address.

3. Transport layer

The transport layer provides end-to-end logical communication between application processes, and has the function of multiplexing and demultiplexing, that is, different application processes of the sender can use a transport layer protocol to transmit data; the transport layer of the receiver can correctly deliver the data to the destination application process after peeling off the header of the message. The transport layer will also carry out error control of messages to improve reliable transmission.

The main protocols in the transport layer are user Datagram protocol UDP and transmission control protocol TCP.

4. Application layer

The application layer provides applications for users.

The main protocols in the application layer are domain name system DNS, file transfer protocol FTP, remote terminal protocol TELNET, hypertext transfer protocol HTTP, simple mail transfer protocol SMTP, mail reading protocol POP3 and IMAP, dynamic host configuration protocol DHCP, simple network management protocol SNMP.

DNS: provide domain name resolution service, provide domain name to IP address translation, using port 53

FTP: transfer files between any computer in a heterogeneous network, using port 21

TELNET: provide users with remote login service, using port 23, using clear code transmission, poor confidentiality, simple and convenient

HTTP: used to implement various links on the World wide Web, that is, the connection between the World wide Web client and the World wide Web server, using port 80

SMTP/POP3, IMAP: provides the transmission of mail, which is used to control the sending, transfer / reading of mail from the mail server.

DHCP: automatically assigns IP addresses to new computers on the network.

SNMP: managing the software and hardware platforms produced by many manufacturers on the Internet Internet

Thank you for reading! This is the end of the article on "several layers of hierarchical structure adopted by the tcp/ip protocol". I hope the above content can be of some help to you, so that you can learn more knowledge. if you think the article is good, you can share it for more people to see!

Welcome to subscribe "Shulou Technology Information " to get latest news, interesting things and hot topics in the IT industry, and controls the hottest and latest Internet news, technology news and IT industry trends.