Circuit Switching and Packet Switching in Computer Networks

Afzal Badshah, PhD
3 min readMay 2, 2024

Circuit switching and packet switching represent two distinct paradigms in data communication. Circuit switching creates a dedicated communication path for the entire duration of a conversation, ensuring a continuous link between devices. In contrast, packet switching involves breaking data into independent packets, allowing for flexible routing and efficient resource utilization across the network. You can also visit detailed tutorials on Data Communication and Computer Networks here.

What is Circuit Switching?

Circuit switching is a communication method where a dedicated communication path or circuit is established between two devices for the duration of their conversation. This path remains open for the entire conversation, ensuring a continuous and dedicated connection.

Traditional telephone networks use circuit switching. When you make a phone call, a dedicated circuit is established between the caller and the receiver for the duration of the call.

Circuit switching

Key Features

  1. Dedicated Path: A dedicated communication path is reserved for the duration of the communication.
  2. Resource Reservation: Resources are allocated in advance, ensuring a constant bandwidth for the entire conversation.
  3. Low Latency: Once the circuit is established, data can be transmitted with minimal delay.

Advantages

  1. Consistent Quality: Since the entire bandwidth is reserved, there is a consistent and predictable quality of service.
  2. Low Latency: Real-time communication is possible with low latency.

Disadvantages

  1. Inefficient Use of Resources: The dedicated circuit remains reserved even during periods of silence, leading to inefficient use of resources.
  2. Limited Scalability: It can be challenging to scale the network to accommodate a large number of users.

What is Packet Switching?

Packet switching involves breaking data into small packets that are transmitted independently over the network. Each packet may take a different route to reach its destination, where they are reassembled to reconstruct the original message.

The Internet primarily relies on packet switching. When you send data over the internet, it is broken into packets, and each packet can take a different route to reach the destination.

Packet switching

Key Features

  1. Packetization: Data is divided into small packets for transmission.
  2. Routing: Each packet can take a different route to reach the destination.
  3. Dynamic Allocation: Resources are allocated on-demand, allowing for more efficient use of network capacity.

Advantages

  1. Efficient Use of Resources: Network resources are utilized more efficiently as they are not reserved exclusively for one conversation.
  2. Scalability: Packet switching is more scalable, making it suitable for large networks with varying traffic.

Disadvantages

  1. Variable Latency: Since packets may take different routes, there can be variable delays in packet delivery.
  2. Potential for Congestion: High network traffic can lead to congestion and packet loss.

Therefore, circuit switching offers a dedicated and predictable connection but can be inefficient, especially for intermittent communication. Packet switching, on the other hand, is more flexible and efficient but may result in variable latency and congestion under heavy loads. The choice between them depends on the specific requirements and characteristics of the communication network.

Activity:
Please, draw a comparison table of circut switching and packet switching.

Material

You can download the presentation here.

Self Assessment Questions

  • What is the primary characteristic of circuit switching, and how does it differ from packet switching in terms of resource allocation?
  • Provide an example of a real-world application that extensively uses circuit switching. What are the advantages and disadvantages of this approach?
  • Explain the concept of packet switching and its role in modern communication networks like the Internet.
  • How does packet switching contribute to efficient resource utilization, and what challenges may arise, particularly under high network traffic conditions?

--

--

Afzal Badshah, PhD

Dr Afzal Badshah focuses on academic skills, pedagogy (teaching skills) and life skills.