What is the relationship between the seven layers of the network and the physical hardware and softw

Interdependence and mutual service are indispensable.

The software runs on the appropriate hardware.

Hardware and software are two interdependent parts of a complete computer system, and their relationship is mainly reflected in the following aspects.

Hardware and software are interdependent.

Hardware is the material basis for software to work, and the normal operation of software is the only way for hardware to play its role. A computer system must be equipped with a well-developed software system in order to function properly and give full play to the various functions of its hardware.

There are no strict boundaries between hardware and software.

With the development of computer technology, in many cases, some functions of a computer can be implemented by both hardware and software. Therefore, there is no absolutely strict interface between hardware and software in a sense.

Hardware and software develop in tandem.

Computer software develops with the rapid development of hardware technology, and the continuous development and improvement of software promotes the updating of hardware, and the two are closely intertwined and developed, and both are indispensable.

The first layer is the physical layer.

The "toiling masses" at the bottom of the OSI model. It transparently transmits the bitstream, which is the transmitted signal. Devices on this layer include hubs, transmitters, receivers, cables, connectors, and repeaters.

The second layer is the data link layer.

This layer is the peacemaker who deals with package structures and fields. On the one hand, it receives data frames from the network layer (layer 3) and encapsulates them at the physical layer; On the other hand, the data link layer encapsulates the raw data bits from the physical layer into frames at the network layer. It plays an important intermediary role.

The data link layer was improved by the IEEE802 plan to include two sub-layers: Media Access Control (MAC) and Logical Link Control (LLC).

Smart hubs, bridges, and network interface cards (NICs) reside at this layer. However, the network interface card also has some coding functions of the physical layer, etc.

The third layer is the network layer.

There's a lot more to do at this level. It works with objects, in a nutshell: circuits, packets, and information exchange.

The network layer determines the path that delivers a packet to its destination. It is to convert a logical network address into a physical address. If packets are too large to reach their destination through one link in the path, the task of the network layer is to divide those packets into smaller packets.

These honorable tasks are assigned to routers, bridge routers, and gateways.

The latter layers are higher layers and usually reside in computers that communicate with each other across the network, unlike the above layers, which can work on their own. Only the gateway in the device can span all layers.

The fourth layer is the transport layer.

Ensure that packets are sent in an error-free order. The transport layer divides a large number of messages from the session layer into manageable packets to be sent to the network.

The fifth layer is the session layer.

A virtual link is established between two applications on separate computers, called a session. The session layer keeps applications in sync by setting checkpoints in the data flow. The session layer does the job of name recognition and security that allows applications to communicate.

The sixth layer, which represents the layer.

Defines the format used by the application to exchange data. In this sense, the presentation layer is also known as a translator. This layer is responsible for protocol conversion, data encoding, and data compression. Programs perform service operations at this layer.

The seventh layer, the application layer, is the highest layer of the OSI model. The application layer presents all network services to the application process. When an application process accesses the network, it performs all actions through this layer.

Throughout the seven floors, from low to high. To make a figurative analogy, from assembly to basic, the higher you go, the weaker the connection with the hardware.

Network cards, network cables, are physical devices.

The data link layer, the switch, the hub, is a little unclear.

In fact, the most important thing is to learn the TIP IP protocol well.

The physical layer, or physical layer, is the lowest layer in the computer network OSI model. The physical layer regulates the creation, maintenance, and dismantling of the physical links required to transmit data, and provides mechanical, electronic, functional, and regulatory characteristics.

Put simply, the physical layer ensures that the raw data can be transmitted over a variety of physical platforms. Both LAN and WAN are Layer 1.

The physical layer is the first layer of OSI, and although it is at the lowest level, it is the foundation of the entire open system. The physical layer provides the transmission** and interconnection of devices for data communication between devices, providing a reliable environment for data transmission. If you want to remember this first layer in as few words as possible, it's "signal and medium."

Count the network cable. Computers don't count. There is also the data transmitted by the network cable.

Layers 1 to 7 are: physical layer, data link layer, network layer, transport layer, session layer, presentation layer, and application layer.

Application layer. Represents the layer.

Session layer. Transport layer (transport layer).

Network layer. Data link layer.

Physical layer. This is the theoretical model of OSI that no one uses

Now the five floors of teaching are:

Messages --- the application layer.

Transport Layer (Transport Layer) - Packets.

Network layer - grouping or datagram.

The data link layer --- frames.

The physical layer --- bits.