VLANKonfiguration

VLANKonfiguration refers to configuring VLANs on network devices to create separate broadcast domains within a local area network. The goal is to control traffic, improve security, and optimize performance by isolating user groups, devices, or services into logical segments. It encompasses design, implementation, and ongoing management.

The de facto standard for VLAN tagging is IEEE 802.1Q, which inserts a VLAN identifier into Ethernet frames. VLAN IDs range from 1 to 4094; VLAN 0 is used for priority tagging, and 4095 is reserved. Native VLAN handling and untagged frames are important for trunk links.

Typical network devices involved are switches with VLAN-capable interfaces, and routers or layer-3 switches for inter-VLAN routing. Ports can be configured as access ports assigned to a single VLAN or trunk ports carrying multiple VLANs. Management VLANs separate administration traffic from user data.

Common steps include planning the VLAN taxonomy, mapping ports to VLANs, configuring switch trunks with allowed VLANs and native VLAN settings, and establishing inter-VLAN routing. Documentation and change control are essential; regular backups of device configurations should be maintained, and consistency across devices should be verified.

Security and operational considerations involve restricting trunk ports, applying access control lists where appropriate, monitoring VLAN health, and avoiding VLAN hopping attacks. Best practices emphasize minimal allowed VLANs per trunk, clear naming conventions, and periodic audits to ensure alignment with policy and growth plans.