A network switch is a common device in most local area networks (LANs). Its primary job is to connect multiple devices, like computers, printers, and servers, within a network, allowing them to communicate with each other efficiently.
Network Switch’s come in a range of sizes as small as 5 ports, to 48 ports, sometimes even larger in enterprise network. Most consumer switches operate at either 100mb/s, 1gb/s (1000mb/s), or 10gb/s.
How Does a Network Switch Work?
Network switches operate at Layer 2 of the OSI model, also known as the Data Link layer. Unlike routers, which use IP addresses to route packets, switches use MAC addresses to switch frames between devices on the same network. Each device connected to a switch has a unique MAC address, which the switch uses to direct network traffic precisely where it needs to go.
When a switch receives a frame, it checks the destination MAC address and refers to its MAC address table to determine which port to send the frame to. This process ensures that data is delivered only to the intended device, minimizing unnecessary network traffic and collisions. ‘Switching’ is often incredibly fast and done using specialized hardware chips within the device instead of a more traditional CPU.
Unmanaged vs. Managed Switches
Network switches come in two main types: unmanaged and managed.
- Unmanaged Switches: These are simple, plug-and-play devices that require no configuration. They are ideal for small networks or home use where basic connectivity is all that’s needed. Unmanaged switches handle all network traffic automatically, without user intervention, and typically offer basic connectivity without advanced features. They do not have a web-interface however typically offer the same performance as a more expensive managed switch.
- Managed Switches: Managed switches provide greater control and visibility over the network. They come with a variety of advanced features that allow network administrators to configure, monitor, and manage the network. Some of the key features include:
- VLANs (Virtual Local Area Networks): VLANs allow the network to be broken up into different logical groups and smaller networks, even if the devices are physically connected to the same switch. This can improve security and performance by isolating certain types of traffic.
- Spanning Tree Protocol (STP): This feature prevents network loops, which can occur when there are multiple paths between switches. Loops can cause serious network issues, such as broadcast storm and is crucial in larger networks.
- Link aggregation: A method of combing multiple physical network connections into a single logical link. This increases bandwidth, improves redundancy, and provides better fault tolerance. An example of this is joining 2x1gbs ports together to make a single 1gb/s link
- Quality of Service (QoS): Ability for the switch to inspect the frame for a prioritise certain types of traffic over another by inspecting the frames for specific tags that indicate priority levels, for example a voice traffic may be prioritised over a congested uplink instead of a print job to improve call quality.
- Simple Network Management Protocol (SNMP): A feature on many networked devices that allows administrators to monitor, manage, and configure network devices remotely. An example of this is an alert sent to a monitoring program every time a network port became active or inactive.
Modernization Over Network Hubs
Network switches have largely replaced older devices known as network hubs. Hubs were basic devices that broadcasted data to all devices in a network, regardless of the destination. This often led to network congestion, inefficiency and presented security risks. Switches are a modern improvement over hubs which instead of broadcasting the same traffic out of every port, only sends the traffic to the port the receiving device is connected to.
Other Types of Switches
Beyond standard unmanaged and managed switches, there are specialized features that
- PoE (Power over Ethernet) Switches: These switches provide both power and data through the single Ethernet cable, this is useful for devices like IP cameras, wireless access points, and VoIP phones as it eliminates the need for separate power supplies for each device. PoE switch’s tend to be considerably more expensive than regular switches, use more power and contain cooling fans within them.
Do you have questions on Network Switch’s? Let us know in the comments below
