Circuit switching is a type of network configuration in which a physical path is acquired and set aside specifically for the purpose of connecting two endpoints in a network for the duration of a dedicated connection. Circuit switching is employed by typical voice phone services.
Using different network devices, Packet switching divides data into smaller units called packets or blocks and transmits them across digital networks.
What is Circuit Switching?
In circuit switching, a dedicated communication channel is set up between the sender and the receiver. Due to the dedicated circuit, there is extremely little chance of data loss or error but a lot of bandwidth is lost because other senders cannot utilize the same channel when a transmission is going on.
Advantages of Circuit Switching
Let’s look at the advantages offered by circuit switching:
- Since a dedicated channel is used, the quality of data transfer is great and the connection is reliable.
- The data transmission rate is fixed.
- Data is delivered in the correct sequence.
- Reduces the amount of waiting time a user spends before and during transmission.
- It is preferable when the communication is long and constant.
Disadvantages of Circuit Switching
And, there also are a few disadvantages. They are as follows:
- The main disadvantage is that since it uses a dedicated channel, it remains occupied and can’t be used for other uses.
- This results in a wastage of bandwidth, and resources can’t be completely utilized.
- It’s costly as dedicated channels are set up for each transmission.
- Establishment of the dedicated channels between the sender and receiver takes additional time.
Example of Circuit Switching
Here are two examples of circuit switching networks:
- Analog telephone networks
- Public Switched Telephone Network or PSTN
What is Packet Switching?
In packet switching, the message is first divided into data packets and then transmitted. It is connectionless, as it doesn’t require a dedicated communication channel. These data packets are then grouped at the receiver’s end to obtain the actual data or message.
Advantages of Packet switching
Some of the advantages offered by packet switching are as follows:
- The packets are dispatched to the destination as soon as they are available. Thus there is no delay in delivery.
- Packet switching can be accomplished without the use of a dedicated connection.
- While transferring packets, many users can share the same channel. Hence, resources are utilized effectively.
- Bandwidth utilization is better.
- It is cost-effective, as no dedicated channels are required to be created.
Disadvantages of Packet Switching
- Data packets can often be lost. Hence, packet switching is not reliable.
- It is not preferred for transmissions with constant usage, such as voice calls.
- As data packets travel through multiple channels, this causes long delays in the transmission of data.
- At times, data packets can arrive in the wrong sequence.
- Due to the utilization of shared physical links, there is the possibility of network security vulnerabilities.
Example of Packet Switching
Packet switching is more useful in the case of data transfer. Thus, a good example of packet switching is ethernet.
Difference between Circuit Switching and Packet Switching
Now, we will look at some points which differentiate circuit switching from packet switching:
| Basis | Circuit Switching | Packet Switching |
|---|---|---|
| Path | To ensure that data transfer occurs, a physical channel is created. | Data is divided into data packets which are sent to the receiver through multiple routes. |
| Bandwidth Reservation | It pre-reserves all of the bandwidth that will be required during the transmission. | It doesn’t reserve any bandwidth. |
| Bandwidth Wastage | A lot of bandwidth is wasted in circuit-switched networks. | No bandwidth is wasted in packet-switched networks. |
| Reliability | Circuit switching is reliable. | Packet switching is not reliable. |
| Layer of OSI model | Physical layer | Network Layer |
| Delay | It’s good for voice transmission since it maintains a consistent latency. | Because the delay is not uniform, it is mostly used for data transfer. |
| Store and forward | There is no concept of the store and forward transmission in circuit switching. | Each node in a packet-switched network can store incoming packets and forward them after they’ve been used. |
How to Choose between Circuit Switching and Packet Switching?
We discussed earlier that packet switching allows users to share bandwidth resources evenly, but it does not guarantee quality or delay. This is useful for data transfer that does not necessitate a real-time response.
Thus, to conclude, in comparison to circuit switching, packet switching is more efficient. Circuit switching, on the other hand, is more efficient than packet switching for voice transmission.
Conclusion
- Switching in computer networks is of three types: circuit, message, and Packet switching.
- In circuit switching, a dedicated communication channel is used between the sender and receiver.
- There is little chance of data loss or error in circuit switching. However, a lot of bandwidth is lost because other senders cannot utilize the same channel when a transmission is going on – this results in a wastage of bandwidth.
- In Packet switching, the message is first divided into data packets and then transmitted.
- Packet switching is connectionless, as it doesn’t require a dedicated communication channel. Packet switching is more useful in case of data transfer than for voice calls or other non-data transmissions.
- Packet Switching is more efficient comparatively than Circuit Switching. However, for voice transmission, the circuit switching technique is more efficient than Packet switching.
FAQs
Q: Is the bandwidth of circuit switching fixed or variable?
A: The bandwidth in circuit switching is fixed and pre-reserved.
Q: In a classic telephone system, what form of switching is used?
A: Circuit Switching.
Q: What kind of switching is used to transfer data?
A: Packet switching.
Q: Which switching mechanism is used to control traffic congestion?
A: Packet switching. Because it ensures that all cable bandwidth is fully utilized.
