Using VLANs for Network Security and Performance
Virtual Networks (VLANs) allow you to segment a physical network into separate logical networks, or broadcast domains, without needing additional hardware. This segmentation not only enhances network performance but also strengthens security and optimizes traffic management.
Why Use VLANs?
VLANs are beneficial in various scenarios:
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Performance: VLANs help manage broadcast traffic, such as DHCP requests or mDNS, which can overwhelm large networks with thousands of clients. By segmenting networks, you can ensure smoother operations and avoid network congestion.
- Example: The port used to connect a PC or workstation can be configured as an Access Port (i.e., it restricts all other VLANs besides the Native VLAN) to avoid congestion from traffic being broadcasted on other VLANs. Learn more about this setup here.
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Security: VLANs operate at Layer 2, meaning that communication between multiple VLANs requires Layer 3 routing at the gateway. This provides an opportunity to implement robust firewall rules and isolation policies.
- Example: Isolate a public guest WiFi from all other VLANs on the network. Read more about isolation strategies here.
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QoS and Policy-Based Routing: By grouping devices and services by functionality—such as "Guest Network," "Employees," or "VoIP"—you can apply the appropriate Quality of Service (QoS) rules or routing policies to meet your organization's business needs.
- Example: Assign high-priority VoIP traffic to a dedicated internet circuit. Find out how to configure this here.
How to Use VLANs
To get started with VLANs, follow these steps:
- Create VLANs based on your network’s structure and needs. See Creating Virtual Networks for a step-by-step guide.
- Assign VLANs to your WiFi SSIDs so clients will be properly segmented when the connect. See Creating WiFi and Broadcasting VLANs for more details.
- Configure switch ports to allow or restrict certain VLANs. See Switch Port VLAN Assignment (Trunk & Access Ports) for more information.
- Configure Firewall Rules to segment your network and isolate VLANs appropriately. See Traffic and Firewall Rules to learn more about implementing security policies.
- Add Policy-Based Routes for enhanced traffic orchestration and QoS. See Policy-Based Routing for more information.