Switch

• A switch is a computer network device that electrically and logically connects together other devices.
• It can receive, process and forward data to the destination device.
• Multiple data cables are plugged into a switch to enable communication between different networked devices.
• When a switch receives a packet of data, it determines what computer or device the packet is intended for and sends it to that computer only.
• It works on network layer of OSI model.

Types

Unmanaged switches

• Unmanaged network switches are frequently used in home networks and small companies and businesses.
• It permits devices on the network to connect with each other, such as computer to computer or printer to computer in one location.
• An unmanaged switch does not necessarily need to be configured or watched.
• They are simple and easy to set up and needs only small cable connections.

Managed switches

• Managed switches can be customized to enhance the functionality of a certain network.
• They are achieved by setting a simple network management protocol.

Smart switches

• Basically the smart network switches are the important types of managed switches.
• Smart switches have a limited set of management features which provide a web interface and accept configuration of basic settings.
• Typically these switches reused for the networking devices such as LAN, port bandwidth and duplex.

Enterprise switches

• Enterprise managed switches are also known as fully managed switches.
• These have capability to fix, copy, transform and display different network configurations.
• These are used in large companies which contained of a large number of connections and nodes, switches and ports.

Advantages

• Packet handling
  These have ability to route packet to the destination.
• Collision management
  Network switches eliminate collisions by creating a direct on-the-fly connection between the sending and receiving devices or computers. This improves performance and efficiency across the network, allowing for complete bandwidth availability.
• Bandwidth utilisation
  Network switches are able to send and receive data at the same time, unlike hubs.
• Problem isolation
  Each device operates on its own wire within a network switch. This makes it easier to pinpoint the area of concern if a problem arises on a given switch port. It also allows other devices to continue to function normally without disruption.

Disadvantages

• Network switches tend to be difficult to install and use.
• While limiting broadcasts switches are not good.
• These have security risks.
• Configuration is necessary when handling multicast packets, which can be complicated.