DevNet Associate (DEVASC) v1.0Network FundamentalsMedium
A network architect is designing a new campus network. The design requires a Layer 3 protocol that can efficiently handle traffic for multiple VLANs, provide redundancy, and support the rapid forwarding of frames without re-encapsulation between subnets on the same device. Which technology meets these requirements?
- ADHCP Relay
- BInter-VLAN Routing with Layer 3 Switch
- CRouter-on-a-Stick
- DNAT (Network Address Translation)
Show answer & explanationAnswer & explanation
Correct answer: B. Inter-VLAN Routing with Layer 3 Switch
Inter-VLAN routing using a Layer 3 switch (also known as a multilayer switch) provides efficient routing between VLANs directly on the switch hardware. This avoids the 'router-on-a-stick' bottleneck and allows for rapid forwarding of frames without re-encapsulation, while offering redundancy capabilities.
Why the other options are wrong
- A. DHCP Relay is used to forward DHCP requests across subnets, not for inter-VLAN routing itself.
- C. Router-on-a-Stick uses a single router interface for multiple VLANs, creating a potential bottleneck due to software forwarding and single point of failure.
- D. NAT translates IP addresses but does not provide inter-VLAN routing or improve forwarding efficiency within a campus network.
Inter-VLAN Routing (Layer 3 Switch)
The process of routing network traffic between different VLANs using a Layer 3 switch, leveraging specialized hardware for high-speed forwarding.
- Uses Switch Virtual Interfaces (SVIs) as default gateways for VLANs.
- Performs routing in hardware (ASICs) for speed.
- More scalable and efficient than 'router-on-a-stick' for campus networks.
Memory trick: Layer 3 Switch: Lightning-fast, Luxurious, Logical routing.