2.
Explanation
Switching is a fundamental concept in data communication that involves the process of directing data from a source to a destination within a network. There are several switching techniques employed for data transmission, each with its own set of components. Here's an overview in 13 points:
1. Switching Definition:
◦ Switching is the mechanism that allows the connection of multiple devices in a network, enabling the exchange of data between them.
2. Circuit Switching:
◦ Components:
▪ Switches: Devices that establish a dedicated communication path between the source and destination for the entire duration of the conversation.
▪ Circuit: The dedicated path or connection between the communicating devices.
3. Packet Switching:
◦ Components:
▪ Packet Switches: Devices that break data into packets and send them independently to the destination.
▪ Packets: Small units of data containing both the actual information and control information.
4. Message Switching:
◦ Components:
▪ Message Switches: Devices that store entire messages before forwarding them to the next switch.
▪ Message: The complete data unit being transmitted.
5. Space Division Switching:
◦ Components:
▪ Crossbar Switches: Utilize a matrix of intersecting switches to establish direct paths between input and output ports.
▪ Control Unit: Manages the opening and closing of crosspoints in the matrix.
6. Time Division Switching:
◦ Components:
▪ Time Slots: Divisions of time during which a dedicated channel is established for communication.
▪ Time Division Switch: Coordinates the allocation of time slots.
7. Frequency Division Switching:
◦ Components:
▪ Frequency Bands: Different frequency bands are assigned to different communication channels.
▪ Frequency Division Switch: Controls the allocation of frequency bands.
8. Message Switching vs. Packet Switching:
◦ In message switching, the entire message is sent before it is forwarded, while packet switching divides data into packets, sending them individually.
9. Connection-Oriented vs. Connectionless Switching:
◦ Connection-Oriented: Establishes a dedicated path before data transfer (e.g., circuit switching).
◦ Connectionless: Does not establish a dedicated path; data is sent independently (e.g., packet switching).
10. Router in Packet Switching:
◦ In packet switching, routers play a crucial role, making decisions based on network protocols and forwarding data packets to their destination.
11. Virtual Circuit in Packet Switching:
◦ Components:
▪ Virtual Circuit: Logical connection established between devices for the duration of a session.
▪ Switching Nodes: Intermediate devices that participate in the establishment and maintenance of virtual circuits.
12. Cell Switching in ATM:
◦ Components:
▪ Cells: Fixed-size data units used in Asynchronous Transfer Mode (ATM).
▪ ATM Switch: Handles the routing and switching of ATM cells.
13. Advantages of Packet Switching:
◦ Efficiency: Efficient use of network resources.
◦ Robustness: Can handle various types of traffic.
◦ Scalability: Scales well with the growing network demands.
Switching techniques, whether circuit, packet, or message switching, involve a set of components that facilitate data transmission within a network. The choice of switching technique depends on factors like network requirements, efficiency, and the type of data being transmitted.