One-Arm Routing Technology Overview | Generated by AI
Question: What technology enables inter-VLAN communication using a single physical router interface?
Answer:
The correct answer is B) One-arm routing.
One-arm routing (also known as router-on-a-stick) allows a router to handle communication between multiple VLANs using only a single physical interface. The interface is configured as an 802.1Q trunk, with logical subinterfaces created for each VLAN. Each subinterface is assigned an IP address in the corresponding VLAN’s subnet, and the router performs inter-VLAN routing by forwarding traffic received on one subinterface to another.
- A) Link aggregation is incorrect—it bundles multiple physical links for increased bandwidth and redundancy but does not enable inter-VLAN routing.
- C) Spanning Tree Protocol is incorrect—it prevents Layer 2 loops in switched networks but has no role in inter-VLAN routing.
- D) VRRP is incorrect—it provides gateway redundancy (virtual IP failover) but does not facilitate routing between VLANs on a single interface.
This configuration is commonly used in smaller networks where dedicating multiple physical router interfaces to VLANs is impractical.