Layer-4 Structure Analysis

When studying the tcp ip protocol, we often confuse the concept of the tcp ip protocol stack with that of the tcp ip protocol. Of course, we should regard the protocol stack as a synthesis of the protocol, and how the protocol is a separate individual. Next, let's take a look at the layer model of the tcp ip protocol stack.

The TCP/IP protocol follows a four-layer model concept: application layer, transport layer, Interconnection layer, and network interface layer.

Tcp ip protocol stack: Network Interface Layer

The basic layer of the model is the network interface layer. Sends and receives data frames. frames are independent network information transmission units. The Network Interface Layer places frames on the Internet or retrieves frames from the Internet.

Tcp ip protocol stack: Interconnection layer

The Interconnection protocol encapsulates data packets into internet data packets and runs necessary routing algorithms. There are four interconnection protocols:

Internet Protocol IP Address: responsible for addressing and routing data packets between the host and the network.

Address Resolution Protocol ARP: Obtain the address of the hardware host in the same physical network.

Internet Control Message Protocol ICMP: sends messages and reports transmission errors of packets.

Internet Group Management Protocol (IGMP): IP host used to report group members to a local multicast router.

Tcp ip protocol stack: Transport Layer

The Transport Protocol provides communication sessions between computers. The selection of transmission protocols depends on the data transmission mode. Two transmission protocols:

Transmission Control Protocol TCP: provides reliable communication connections for applications. It is suitable for transmitting a large amount of data at a time. It is applicable to applications that require responses.

User Datagram Protocol (UDP): provides connectionless communication and does not guarantee reliable transfer packets. It is suitable for transmitting a small amount of data at a time, and the reliability is the responsibility of the application layer.

Tcp ip protocol stack: Application Layer

Applications access the network through this layer.

Network Interface Technology

The IP uses the network device interface specification (NDIS) to submit frames to the network interface layer. IP addresses Support WAN and domestic network interface technologies.

Serial Line Protocol

Generally, tcp ipg transmits data over the serial line protocol SLIP or Point-to-Point Protocol PPP over the serial line protocol.