A network switch sits at the centre of many wired networks. Choosing one should start with the devices it needs to connect and the requirements of the network around it.
Practical example: segmenting a 45-user office
Select network equipment from traffic, management and growth requirements.
Scenario: One managed switching environment carries servers, staff devices, VoIP, CCTV and guest WiFi.
| Example VLAN | Purpose | Example policy |
|---|---|---|
| 10 | Servers | Accessible only from authorised business networks |
| 20 | Staff | Access to approved internal services and Internet |
| 30 | Voice | Restricted to required voice and management services |
| 40 | CCTV | Camera traffic restricted to required recording and management systems |
| 50 | Guest WiFi | Internet access, blocked from internal business networks |
Decision: VLANs provide the logical separation. The router, firewall or Layer 3 policy determines which networks may communicate.
Common mistakes and selection checklist
Common mistakes
- Creating VLANs but allowing unrestricted routing between them.
- Using VLAN IDs without documenting IP subnets, DHCP, gateways and access policy.
- Configuring trunk and access ports inconsistently across switches and access points.
What happens if you get it wrong?
The network can look segmented while providing little security benefit, or devices can lose connectivity because tagged and untagged traffic is handled differently at each hop.
Selection checklist
- Define the purpose and subnet of every VLAN.
- Document which VLANs may communicate and on which services.
- Configure gateway or Layer 3 firewall policy explicitly.
- Verify access ports, trunks and native or untagged VLAN behaviour end to end.
- Test DHCP, DNS, Internet access and blocked inter-VLAN paths after deployment.
Start with the connected devices
Make a list of the equipment that will connect to the switch. This can include servers, workstations, access points, printers, storage systems, cameras and other network devices.
Count the ports
Choose enough ports for the current installation while allowing sensible room for expansion. Port count is not the only consideration, but running out of ports shortly after installation is an avoidable problem.
Consider network speed
Check the required speed of the connected devices and the links between switches. A network may contain a mixture of connection speeds, so the switch should support the required combination.
Managed or unmanaged?
An unmanaged switch is designed for straightforward connectivity. A managed switch provides configuration and monitoring capabilities that can be important in larger or more controlled networks.
Read Managed vs Unmanaged Switches
Do you need PoE?
Power over Ethernet can deliver power and network connectivity over Ethernet cabling to compatible devices such as wireless access points, IP cameras and some other network equipment.
Check uplinks
If the switch connects to another switch, server, storage system or network core, check the available uplink speeds and interfaces. The uplink can be important to the overall design.
Plan for growth
Consider whether additional users, access points, cameras, servers or other devices are likely to be added. Network equipment can remain in service for years, so the initial design should not be based only on today's port count.
- Number of connected devices
- Required port speeds
- Port count and expansion
- Managed or unmanaged operation
- PoE requirement and power budget
- Uplink speed and interface
- Rack or desktop installation
- Expected future growth
Port count alone does not define a suitable switch. Speed, management, PoE and uplinks all form part of the decision.
Confirm the exact product specification, supported configuration and compatibility before ordering. Platform generation, firmware, licences and optional components can change what a product supports.