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Implement InterVLAN Routing

LAN Switching and Wireless – Chapter 6

Version 4.0

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Objectives
 Explain to the satisfaction of a qualified instructor how network traffic is routed between VLANs in a converged network.
Configure inter-VLAN routing on a router to enable communications between end-user devices on separate VLANs Troubleshoot common inter-VLAN connectivity issues.

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Explain How Network Traffic is Routed Between VLANs in a Converged Network
 Describe the routing options between VLANs

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Inter-VLAN routing is a process of forwarding network traffic from one VLAN to another VLAN using a router. VLANs are associated with unique IP subnets on the network. (Each VLAN equals 1 subnet!) This subnet configuration facilitates the routing process in a multi-VLAN environment.

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Explain How Network Traffic is Routed Between VLANs in a Converged Network
 Describe the role of interfaces and subinterfaces in supporting inter-VLAN routing
Traditional interVLAN routing requires multiple physical interfaces on both the router and the switch. Some router software permits configuring router interfaces as trunk links.

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Explain How Network Traffic is Routed Between VLANs in a Converged Network
 Describe the role of interfaces and subinterfaces in supporting inter-VLAN routing
The router interface is configured to operate as a trunk link and is connected to a switch port configured in trunk mode.
The router performs the inter-VLAN routing by routing between the VLANs using subinterfaces.

Subinterfaces are multiple virtual interfaces, associated with one physical interface..
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Configure Inter-VLAN Routing
 Describe the steps to configure inter-VLAN routing

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Configure Inter-VLAN Routing
 Describe the steps to configure interVLAN routing 

Each subinterface is assigned an IP address specific to the subnet that it will be part of and configured to VLAN tag frames for the VLAN that the interface is to interact with.

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Configure Inter-VLAN Routing

Subinterfaces allow a router to scale to accommodate more VLANs than the physical interfaces permit.

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Troubleshoot Common Inter-VLAN Connectivity Issues
 Describe the common switch configuration Issues

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Troubleshoot Common Inter-VLAN Connectivity Issues
 Describe the common router configuration issues

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Troubleshoot Common Inter-VLAN Connectivity Issues
 Describe the common IP Addressing Issues

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Summary
 Inter-VLAN routing is the process of routing information between VLANs
 Inter-VLAN routing requires the use of a router or a layer 3 switch  Traditional inter-VLAN routing
Requires multiple router interfaces that are each connected to separate VLANs

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Summary
 Router on a stick
this is an inter-VLAN routing topology that uses router sub interfaces connected to a layer 2 switch. Each Subinterface must be configured with: An IP address Associated VLAN number

 Configuration of inter VLAN routing
–Configure switch ports connected to router with correct VLAN
–Configure each router subinterface with the correct IP address & VLAN ID

 Verify configuration on switch and router

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