Professional_VLAN_Presentation what are

Professional_VLAN_Presentation what are

• 1.
  VLAN: From Basicsto Advanced Concepts A professional guide covering beginner to expert level VLAN concepts
• 2.
  Introduction to VLANs •Definition: VLAN (Virtual Local Area Network) logically segments a LAN. • Purpose: Improve security, reduce broadcast traffic, and simplify management. • Analogy: Dividing one large office into multiple departments.
• 3.
  LAN vs VLAN •Traditional LAN: Single broadcast domain, all devices connected together. • VLAN: Segmented logical networks, independent of physical topology. • Benefits: Security, performance, and easier management.
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  VLAN Types • DefaultVLAN – VLAN 1, present on all ports by default. • Data VLAN – For user-generated traffic. • Voice VLAN – Dedicated to IP phones. • Management VLAN – For switch management traffic. • Native VLAN – Carries untagged traffic on trunk ports.
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  VLAN Benefits • Enhancedsecurity and isolation • Reduced broadcast domains • Simplified network management • Better performance and scalability
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  VLAN Tagging (802.1Q) •Diagram: Ethernet frame with 4-byte VLAN tag • TPID | TCI | VLAN ID • Used on trunk links to identify VLANs
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  Access vs TrunkPorts • Access port: Connects end devices, carries single VLAN. • Trunk port: Connects switches/routers, carries multiple VLANs. • Trunk uses 802.1Q tagging to distinguish VLANs.
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  Cisco VLAN ConfigurationExamples • Access Port: • Switch(config)# interface fa0/1 • Switch(config-if)# switchport mode access • Switch(config-if)# switchport access vlan 10 • Trunk Port: • Switch(config)# interface fa0/24 • Switch(config-if)# switchport mode trunk • Switch(config-if)# switchport trunk allowed
• 9.
  Inter-VLAN Routing • Router-on-a-stick:Single router interface with subinterfaces for each VLAN. • Layer 3 Switch: Uses SVIs (Switch Virtual Interfaces) for inter-VLAN routing. • Allows communication between different VLANs.
• 10.
  Advanced VLAN Topics •Private VLANs (Primary, Isolated, Community) • Dynamic VLAN assignment (VMPS or RADIUS) • Voice VLAN QoS considerations • VLAN hopping attack and prevention
• 11.
  VLAN Troubleshooting • CheckVLAN and trunk configuration. • Common issues: VLAN mismatch, native VLAN misconfiguration. • Useful commands: show vlan brief, show interfaces trunk, show vtp status
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  Best Practices • Avoidusing VLAN 1 • Use unique native VLANs • Disable unused ports and assign to unused VLAN • Use ACLs for inter-VLAN security • Plan VLAN IDs logically by department or function
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  Summary • VLANs providelogical segmentation within LANs. • Enhance security, performance, and manageability. • Essential for modern enterprise networks.