Switching in Computer Network
Switching is the process of using specialized devices called switches to move data packets between devices in a network or between networks. Switching is a constant process for a computer user.
In the OSI Model, switching occurs at the Data Link layer. This indicates that switching is the first step in data communication after data packets are generated in the Physical Layer.
Full-duplex mode on switches reduces the possibility of packet collisions by enabling simultaneous communication between devices. Because switches target specific destinations, they use bandwidth more efficiently than traditional hubs, which broadcast messages to all connected devices.
Types of Switching in Computer Networks
Three categories of switching techniques exist:
- Message Switching
- Circuit Switching
- Packet Switching
1. Message Switching
An older switching method that is no longer in use is message switching. The message switching technique is extremely wasteful because it forwards the whole data block or message over the network.
The complete message is received by intermediate nodes, which store it before sending it on to the following node in the path. Dynamic routing and effective resource use are made possible by this "store and forward" strategy, but it can also cause delays and necessitate significant storage at each node.
Benefits of Message switching:
- By buffer communications in the event that resources are unavailable, the store and forward technique can aid in reducing network congestion.
- Efficiency can be increased by transferring numerous messages at once over a single channel.
- Because message switching enables dynamic routing, a message's path can be modified in response to network conditions.
- Message switching is less appropriate for applications that need quick response times because of the delays involved.
- The cost of store and forward devices can be high, which raises the system's overall cost.
- Before forwarding the message, intermediate nodes must hold the complete message, which necessitates a large amount of storage space.
2. Circuit Switching
For the duration of a communication session, circuit switching creates a dedicated, fixed-bandwidth link between two endpoints.Although this approach can be ineffective and expensive, it ensures a steady, dependable connection with consistent performance.
Benefits of Circuit switching:
- It is appropriate for applications needing consistent performance and quality since a dedicated path guarantees an ongoing, unbroken connection.
- Only the connected parties have access to the secure communication line provided by the dedicated channel.
- Data transfer happens with little delay once the circuit is set up, which makes it appropriate for real-time applications.
Drawbacks of circuit switching include:
- Even when no data is being sent, the dedicated channel is still reserved, wasting bandwidth and using resources inefficiently.
- Only circuit-switched network traffic may use the dedicated channel; other kinds of data cannot be sent over the same channel.
- It can be costly to set up and maintain a separate circuit for every connection, particularly for sporadic or low-volume data transfer.
3. Packet Switching
The data must be divided into smaller parts, known as data frames or packets, in order to use this technique. Following that, these data frames are sent to their destinations based on the network's resources at that specific moment.
Modern computers and even the Internet use this kind of switching. Each data frame in this case includes extra destination information as well as other information needed for a successful transmission across network components.
Benefits of Packet switching:
- By enabling several users to share a channel and dynamically routing packets, packet switching maximizes the usage of network resources.
- Growing network demands can be readily accommodated by packet switching networks without requiring major changes to the infrastructure.
- Voice, video, and text are just a few of the data kinds that packet switching can handle.
- Packet switching needs extra security measures to safeguard data in the absence of dedicated channels.
- Managing network congestion and dynamic packet routing can be challenging.
- Longer pathways taken by packets can result in delays and higher latency.
