What are the different types of network switches?

Nowadays a switch is a switch, right? Well, not necessarily. While all network switches move data from point A to point B, many enterprise switches have important hardware and software differences that are considered in any IT infrastructure deployment. Let’s take a look at the different types of network switches available in the market today.

1. Unmanaged, intelligent and managed switches

Understanding the level of management and configurability of a network switch is one of the most important purchasing decisions a network architect must make. For small branch offices or work-from-home offices, an unmanaged switch can do the trick. These switches are essentially plug-and-play units that allow multiple devices to communicate over a single broadcast domain. Due to their limited capabilities, unmanaged switches are considerably less expensive than smart and managed switch alternatives.

When comparing the differences between smart and managed switches, things start to get a bit murky. Both devices are technically handy devices. However, in most cases, network equipment vendors that sell smart switches tend to remove many of the more advanced features and only include the basics, such as virtual LAN (VLAN) creation, basic QoS settings, port trunking, and some tree protocol options. Smart switches are typically configured through a web-based graphical interface, as opposed to a command line interface (CLI).

Managed switches, on the other hand, are at the top of the switch food chain. These switches offer hundreds to thousands of configuration options, many of which are very useful for medium to large enterprise LANs. Additionally, the management of these devices may include a graphical interface, but more often than not they are managed through the command line interface for speed and ease of use by trained network professionals.

2. Layer 2 and Layer 3 switches

With a continued focus on managed switches, these can be further segmented into two distinct types of functionality. They are generally referred to as Layer 2 and Layer 3 switches depending on where they operate on the OSI model. Layer 2 switches are also called multiport bridge switches, while Layer 3 switches are sometimes referred to as multilayer switches.

Layer 2 switches can intelligently move data frames from one port to another on the same VLAN. However, the data that needs to be moved between VLANs, also known as inter-VLAN routing – needs a device that can route IP packets. When using Layer 2 switches, this step is often done with an external router using a one-arm architecture.

For large networks with multiple VLANs and a lot of routing between them, it is often easier and more efficient to combine the capabilities of a Layer 2 switch and a router into a single hardware and software device. This is precisely what a Layer 3 switch does.

Instead of relying on an external device to route traffic between VLANs, a Layer 3 switch can be configured to do so through its own internal switching. backplane. So, for LANs that require a routing component, a Layer 3 switch reduces the network equipment footprint and increases performance over single-arm designs that rely on an external routing component.

3. Power over Ethernet switches

Power over Ethernet (PoE) is the ability to send low voltage electricity over the same twisted pair copper cable that is used to transmit and receive data. This feature is used to power wireless access points (APs), IP phones, and many IoT devices.

If PoE is not required in any capacity, non-PoE switches are a cheaper option. However, for those who need PoE, a few more steps are needed to ensure that the PoE endpoints are receiving sufficient power.

PoE standards, as dictated by the IEEE, specify the maximum power that can be transmitted through copper cabling. Depending on the termination point, more or less power may be required. For example, a typical IP phone can be powered via PoE using a PoE port that can transmit up to 15.4 watts (W) of power. On the other hand, modern Wi-Fi 6 and Wi-Fi 6E hotspots can require significantly more power to operate. Thus, a PoE switch only capable of delivering the IEEE 802.3af standards will not suffice.

Below is a list of PoE standards and the maximum power that can be delivered in the recommended category of twisted pair cables:

PoE standard IEEE 802.3af IEEE 802.3at IEEE 802.3bt (Type 3) IEEE 802.3bt (Type 4)
Maximum power 15.4 W 30 W 60W 90 W
Recommended wiring Cat3 and Cat5 Cat5 or better Cat5 or better Cat5 or better

4. Fixed, modular and stackable switches

From a physical standpoint, network switches come in three different types of hardware configuration:

  1. Fixed switches. With fixed switches, ports, interfaces, power supplies, and cooling fans are defined and cannot be changed, added, or changed. Additionally, fixed switches cannot be stacked on top of other switches to create a single logical switch to manage from.
  2. Stackable switches. Stackable switches are fixed switches that include a backplane cable interface to connect multiple switches together to create a single logical switch made up of two or more physical switches. This can increase switch-to-switch data transport speed, as well as simplify stack management because multiple physical switches are managed as if they were. one switch. Some stackable switches can also share power between each stack. Thus, if a switch in the stack has experienced a power failure, it can continue to operate by taking unused power capacity from other switches in the stack.
  3. Modular switches. Modular or chassis-based switches provide the ability to fit switch cards into a large, fixed-form-factor chassis that can support two or more cards. This type of switch offers the most flexibility and scalability as the switch interfaces can be swapped out as needed. Additionally, if a card fails on a modular switch, a field technician can hot swap the faulty card without turning off the switch assembly. Finally, it’s common for modular switches to be able to swap out power supplies and cooling fans when upgrades are needed or outages occur.