Switch classificationcomprehensive analysis of switch types and characteristics-Bek Industrial Communications

I. Classification according to the working level of switches

In computer networks, a switch is an important network device used to realize data transmission between computers in a local area network. According to the working level of switches, switches can be classified into the following categories:

1.1 Physical layer switch

The physical layer switch operates at the lowest level of the computer network and is mainly responsible for forwarding network data to the target device. It transmits data from one port to another through a physical interface to realize the connection of computers in a local area network. The characteristics of a physical layer switch include:

Operating at the physical layer, with high speed and low latency;
Unable to recognize the content of data packets and can only forward them according to physical addresses;
Does not have the functions of the network layer and transport layer.

1.2 Data link layer switch

The data link layer switch operates on the second layer of the computer network and is mainly responsible for forwarding data according to MAC addresses. It can recognize the source MAC address and target MAC address of data packets and forward the packets to the target device. The characteristics of a data link layer switch include:

Operating at the data link layer, enabling direct communication between computers in a local area network;
Realizing rapid forwarding of data packets by learning and establishing a MAC address table;
Usually having functions such as VLAN and STP to provide reliability and security of the network.

1.3 Network layer switch

The network layer switch operates on the third layer of the computer network and is mainly responsible for forwarding data according to IP addresses. It can recognize the source IP address and target IP address of data packets and forward the packets to the target device. The characteristics of a network layer switch include:

Operating at the network layer, enabling communication between different subnets;
Forwarding data packets through routing tables and supporting multiple routing protocols;
Usually having functions such as ACL and QoS to provide security and quality of service of the network.

1.4 Transport layer switch

The transport layer switch operates on the fourth layer of the computer network and is mainly responsible for forwarding data according to port numbers. It can recognize the source port number and target port number of data packets and forward the packets to the target device. The characteristics of a transport layer switch include:

Operating at the transport layer, enabling end-to-end communication;
Realizing flexible forwarding of data packets through port mapping and forwarding strategies;
Usually having functions such as load balancing and traffic control to provide reliability and performance of the network.

II. Classification according to the usage scope of switches

In addition to classification according to the working level, switches can also be classified according to their usage scope. According to the usage scope, switches can be classified into the following categories:

2.1 Enterprise switch

An enterprise switch refers to a switch used in the internal local area network of an enterprise. It usually has a large number of ports and high-performance forwarding capabilities, which can meet the data transmission needs of a large number of computers within an enterprise. The characteristics of an enterprise switch include:

Multiple ports, supporting the connection of multiple computers;
High-speed forwarding capability to ensure the efficiency of data transmission;
Supporting functions such as VLAN and QoS to provide security and quality of service of the network.

2.2 Home switch

A home switch refers to a switch used in a home local area network. It usually has a small number of ports and a simple configuration method, suitable for home users. The characteristics of a home switch include:

A small number of ports, meeting the connection needs of a small number of computers within the home;
Simple configuration, convenient for home users to use;
Usually does not support advanced functions such as VLAN and QoS.

2.3 Data center switch

A data center switch refers to a switch used in a data center. It usually has a large number of ports and a high-density port layout, which can meet the connection needs of a large number of servers in a data center. The characteristics of a data center switch include:

A large number of ports, supporting the connection of a large number of servers;
High-density port layout, saving cabinet space;
Supporting advanced functions such as VLAN, QoS, and load balancing.

III. Classification according to the working mode of switches

In addition, switches can also be classified according to their working mode. According to the working mode, switches can be classified into the following categories:

3.1 Store-and-forward switch

A store-and-forward switch refers to a switch that makes forwarding decisions after receiving a complete data packet. It first stores the received data packet in a buffer, then parses and processes the data packet, and finally forwards it. The characteristics of a store-and-forward switch include:

High forwarding accuracy, able to check the integrity and validity of data packets;
Low forwarding latency, suitable for scenarios with high latency requirements;
Suitable for processing various types of data packets.

3.2 Cut-through switch

A cut-through switch refers to a switch that makes forwarding decisions while receiving a data packet. It does not need to store the data packet in a buffer but directly parses and processes the data packet and forwards it immediately. The characteristics of a cut-through switch include:

Low forwarding latency, suitable for scenarios with extremely high latency requirements;
Does not support checking the integrity and validity of data packets;
Suitable for processing applications with high latency requirements such as real-time streaming media.

3.3 Adaptive switch

An adaptive switch refers to a switch that automatically adjusts the forwarding mode according to network traffic and load conditions. It can select the most appropriate forwarding mode according to the actual situation of the network to provide the best performance and quality of service. The characteristics of an adaptive switch include:

Automatically select store-and-forward or cut-through forwarding mode according to network load conditions;
Support dynamic adjustment of forwarding strategies to provide flexible performance optimization;
Suitable for scenarios with large changes in network traffic.

Conclusion

Through a comprehensive analysis of the classification and characteristics of switches, we can better understand the working principle and application scenarios of switches. Different types of switches have their own advantages and application values in different network environments. When choosing and deploying switches, we should consider actual needs and budgets and choose the most suitable switch type to provide stable and efficient network services.