Circuit switchingprinciples, advantages and disadvantages, and applications-Bek Industrial Communications

一、What is Circuit Switching Technology?

Circuit switching technology is a communication technology based on circuits, one of the foundations of modern communication systems. In circuit switching, communication signals are transmitted over a dedicated communication line between the communicating parties after a connection is established, and this line is exclusively occupied by both parties until the communication ends. Circuit switching can achieve high-quality communication but has been gradually replaced by more advanced packet-switched technology due to its high resource consumption.

二、Principle of Circuit Switching Technology

The principle of circuit switching technology involves three main steps: establishing a connection, transmitting data, and releasing the connection.

1.Establishing a Connection

In circuit switching, communication parties must first establish a connection before communication can occur. The process of establishing a connection includes the following steps:

Initiating a Call: The calling party sends a call request signal to the switch.
Addressing and Routing: The switch performs addressing based on the call request signal and selects an appropriate route.
Call Signal Transmission: The switch transmits the call request signal to the switch at the target address.
Call Confirmation: The switch at the target address receives the call request signal and sends a call confirmation signal back to the calling party.

2.Transmitting Data

After the connection is established, data transmission can begin. In circuit switching, data transmission occurs over a dedicated communication line that is exclusively occupied by both parties throughout the communication. The communication signal passes through a series of switches for relay until it reaches the target address.

3.Releasing the Connection

Once communication is complete, the parties need to release the connection. The process of releasing the connection includes the following steps:

Initiating Release: One of the communicating parties sends a release request signal to the switch.
Release Signal Transmission: The switch transmits the release request signal to the other switch.
Release Confirmation: The other switch receives the release request signal and sends a release confirmation signal back to the initiating party.

三、Advantages and Disadvantages of Circuit Switching Technology

Circuit switching technology has several advantages:

High Communication Quality: Due to the use of a dedicated communication line, the quality of communication is high, and it is stable and reliable.
Suitable for Real-Time Communication: Circuit switching technology is suitable for applications that require high real-time communication, such as telephone communication and video conferencing.
High Transmission Efficiency: Since the communication line is exclusively occupied, the transmission efficiency is high.

However, circuit switching technology also has some disadvantages:

High Resource Consumption: In circuit switching, the communication line is exclusively occupied, leading to resource wastage, especially when the communicating parties do not continuously communicate.
Poor Flexibility: Once the connection is established, the communication line is occupied by both parties, which cannot accommodate the needs of multiplexing.
High Maintenance Cost: Circuit switching technology requires the establishment and maintenance of a large number of communication lines, so the maintenance cost is high.

四、Applications of Circuit Switching Technology

Circuit switching technology has wide applications in the communication field, including:

1.Telephone Communication

Circuit switching technology is the foundation of traditional telephone communication, allowing telephone users to communicate vocally after establishing a connection.

2.Fax Communication

Fax communication is a method of transmitting documents as images, and fax machines use circuit switching technology to transmit documents to the receiving fax machine.

3.Leased Line Communication

Circuit switching technology can provide stable communication quality, suitable for applications that require stable communication, such as railway communication and power communication.

4.Video Conferencing

Video conferencing is a way of conducting remote meetings over the network, and circuit switching technology can provide high-quality video transmission to ensure the smooth progress of the meeting.

Five: Summary

As one of the fundamental technologies in communication, circuit-switched technology has been widely used in traditional communication fields. It enables communication by establishing a connection, transmitting data, and releasing the connection, offering advantages such as high communication quality, suitability for real-time communication, and high transmission efficiency. However, circuit-switched technology also has drawbacks, including high resource occupation, poor flexibility, and high maintenance costs. With the development of packet-switched technology, circuit-switched technology has been gradually replaced. Nonetheless, in certain specific application scenarios, circuit-switched technology still plays a vital role.