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products:ict:communications:courses:cisco:ccna:verifying_inter_vlan_routing_configurations

Inter-VLAN routing configurations. This process enables communication between different VLANs within a network. I'll provide an overview of the three common methods for implementing inter-VLAN routing:

1. Traditional Inter-VLAN Routing:

  1. In this method, a router with multiple physical interfaces connects to a switch. Each interface corresponds to a VLAN.
  2. The switch ports connected to the router are set to access mode, and each router interface becomes the default gateway for hosts in its associated VLAN.
  3. When hosts from one VLAN need to communicate with hosts in another VLAN, the traffic is routed through the router.
  4. Example: If Host A (VLAN 10) wants to send a message to Host B (VLAN 20):

1. Host A checks if the destination IP address is within its VLAN.

   2. If not, the traffic is forwarded to the router's default gateway (interface Fa0/0).
   3. Host A sends an ARP request to the switch to find the router's MAC address.
   4. The frame is unicast to the router, which then forwards it to the trunk interface.
   5. The router determines the destination IP address and interface from its routing table¹.

2. Router-on-a-Stick Inter-VLAN Routing:

  1. In this method, a single physical interface on the router connects to the switch.
  2. The router creates subinterfaces for each VLAN, and each subinterface corresponds to a VLAN.
  3. The router-on-a-stick approach allows multiple VLANs to share the same physical link.
  4. Example: The router processes VLAN traffic based on the subinterface configuration¹.

3. Multilayer Switch Inter-VLAN Routing:

  1. Multilayer switches (Layer 3 switches) can perform inter-VLAN routing without an external router.
  2. These switches have VLAN interfaces (SVIs) for each VLAN, acting as virtual router interfaces.
  3. They route traffic between VLANs directly within the switch.
  4. Example: The multilayer switch routes traffic between VLANs using its SVIs¹.
products/ict/communications/courses/cisco/ccna/verifying_inter_vlan_routing_configurations.txt · Last modified: 2024/04/01 03:08 by wikiadmin