Networking Switch Ports Explained

Networking Switch Selector

Devices are connected to networking switches through ports, however, different devices are supported by different ports and cabling. When choosing the right switch for you and your business it is important to assess what devices need to be connected and the ports that will support them, as well as the speed that each port will need to be capable of supporting. Cables that support this speed will also be needed to create a networking system that is fully compatible and that works to its full potential.

What You'll learn:

  • Definitions of key networking ports. 
  • The functions of different networking switches and why you may want to consider them. 
  • Cables that can be used to connect into network ports and their pros and cons. 


Networking switches are able to identify connected devices by the port they are connected to and can transfer data to specific devices as a result. By using a MAC address table, switches store information on connected hardware, including which port each is connected to. With Multiport switches, this is essential for the efficient running of the network as it allows data transfer to as many devices as required without sending information to all connected equipment as standard.

Network switch ports

These devices also feature a collision domain using CSMA/CD (Carrier Sense Multiple Access with Collision Detect) software, that allows every single port to operate in full duplex (send and receive data at the same time) without collisions occurring. This software enhances device efficiency and helps the switch function well under heavy traffic.


Switches can feature a single port for small, individual networks or they can support multiport technology. Multiport switches can offer a variety of port counts depending on the size of your business and network; small businesses may require switches with 8-10 ports; however, a large enterprise-grade switch may include 48. However, as different devices are supported by different cables and ports, multiport switches may contain a variation of port types to support a range of devices, as well as a faster data transfer rate.


What is RJ45

RJ45 stands for registered jack 45 and is often mistaken for Ethernet or CAT6. CAT6 cables have an RJ45 connector on each end and these two features, as well as RJ45 ports, make up an Ethernet connection. RJ45 refers to both the male (connector) and the female (port) aspects of an ethernet network and it is the most common method for data transfer between devices. Because of this, most switches will feature an RJ45 port, or multiple, as standard as most devices will be compatible with your switch through this connection.


In terms of speed, different ethernet cables can provide a range of speeds and data transfer rates depending on your network requirements; ensuring that your cables and connected devices support a shared maximum speed and transfer rate is essential for allowing your network to work at its full potential.



What is a Transceiver?

A transceiver is a module that is both a combination of transmitter and receiver in one device. Most transceivers are wireless, but in the case of networking switch ports, they deal with cable and fibre optic solutions.


What is SFP?

SFP stands for small form-factor pluggable and refers to a port or transceiver module found in some networking switches. SFP ports provide a high-speed and reliable connection option between devices through copper or fibre optic cables. They are a great option for many large networking solutions due to the secure and exceptionally fast connections they provide.


What is SFP+?

SFP+ looks and acts identically to an SFP module, however, it is capable of supporting up to 10Gbps. SFP+ is recommended for larger networks with many connected devices to avoid bottlenecks and keep information moving between devices efficiently. SFP+ allows your network to make use of faster cabling and device options, such as single or multi-mode fibre.


Choosing between SFP and SFP+ is a case of assessing how much demand will be on your network system and deciding on the best port option to support your business's needs. For small to medium networks, SFP is a good choice and provides high-speed, reliable connections. For larger networks, higher speeds and transfer rates will prevent bottlenecking and ensure network efficiency.



GBIC is another hot-swappable transceiver. It stands for Gigabit Interface Converter and it is generally used to convert between the optical and electrical signal. SFP is seen as an upgraded GBIC module and the only real difference between the two is size, with SFP being a much smaller choice.




QSFP stands for quad small form-factor pluggable and this module works in the same way as an SFP or SFP+ transceiver. QSFP supports ethernet, fibre channel, InfiniBand and SONET/SDH with varying options on data transfer rate. This transceiver provides 4 transmit and 4 receiver channels to support higher data transfer rates for your network solution. QFSP supports a 4x1Gbps or 40Gbps, transfer rate making it a faster option than SFP or SFP+ modules.


QSFP+ is an even faster option, offering 4x10Gbps, or 40Gbps, data transfer rate for large networking solutions. When deciding on the transceiver for your network it is worth considering the applications of your business and the number of connected devices to assess the speed and transfer rate that your network will need.


What is CX4?

CX4 ports are capable of supporting a 10-Gigabit Ethernet connection, making this port a good choice when installing hardware for a 10GBoE network system. By combining low-latency, low cost and reduced power consumption, CX4 ports offer a great choice for demanding applications and networks with heavy levels of traffic whilst ensuring high levels of efficiency and productivity for your network.


CX4 ports provide a reliable and exceptionally fast networking option to support a 10GbE IT system. Find out more about 10GbE networking solutions in our blog on switch speeds.


Which Port do I need?

Look at the workings of your business and your IT needs when thinking about which ports would work best for your business. Choosing or upgrading a switch's ports is dependent on the devices in your network, as well as the cables you are using and the capabilities of the switch itself.


The number of connected devices, as well as the demand of the applications you are running, should be determined to help decide which port is best for your business in terms of speed, data transfer rate and the number of ports available. Our team is available to offer any advice, recommendations or industry-leading support on this decision. Get in touch here.


Want to browse your switch options? Our networking configurator tool helps you identify your perfect networking device by allowing you to select options that best fit your IT needs and narrowing down the selection of devices on offer to those that will work best for you. Head to our networking configurator to select a device that works for you and your business here.


Accompanying Cables

The most common cabling for your networking switch is UTP, or Unshielded Twisted Pair. This cabling is basic in design and consists of two copper wires twisted together with no shielding. The twisted pair affect performance characteristics such as crosstalk and attenuation.

Twisted pair cables come in a range of categories:



Max cable length

Cat 5

100Mbps at 100MHz


Cat 5e

1,000Mbps at 100MHz



1,000Mbps at 250MHz



Straight Through vs Crossover Cables

Straight through cables are the most common as they are used to connect non-similar devices, such as a computer to a switch. Crossovers, in comparison, are used to connect devices that are similar to one another, such as computer to computer, or switch to switch. However, even if the wrong cable is used, switches are now capable of correcting the signals.


Single Mode vs Multimode

Fibre cables generally come in either sm- single mode and mm- multimode. Single mode is generally more expensive as it allows a faster transmission rate between connected devices. They are also able to transfer data over much larger distances, (even up to 70 miles!) than multi-mode without hurting the signal.

Multimode on the other hand, is cheaper and easier to establish. Multimode has a much shorter maximum distance of 7 miles due to the fact that the core is a lot thicker than a single mode cable and there are multiple light waves being transmitted at once. Multimode is a good choice for lower speed networks or systems where distance is not an issue. For a more complex and high speed option, it is worth considering single-mode cables.

Networking Switch Selector