Implementing and Operating Cisco Enterprise Network Core Technologies (ENCOR) v1.2ArchitectureMedium
A network architect is evaluating different virtualization technologies for expanding a data center. The goal is to isolate applications and services from each other at the network layer, allowing them to run independently on shared physical infrastructure. This isolation should extend beyond simple VLANs to provide complete separation of routing tables and forwarding instances. Which network virtualization technology is best suited for this requirement?
- AVSANs (Virtual Storage Area Networks)
- BVLANs (Virtual Local Area Networks)
- CVRFs (Virtual Routing and Forwarding)
- DVXLAN (Virtual Extensible LAN)
Show answer & explanationAnswer & explanation
Correct answer: C. VRFs (Virtual Routing and Forwarding)
VRFs (Virtual Routing and Forwarding) enable multiple independent routing tables and forwarding instances to exist on a single router or switch. This provides complete network layer isolation between different applications or tenants, allowing them to share physical infrastructure while maintaining separate routing domains and avoiding IP address conflicts.
Why the other options are wrong
- A. VSANs are for storage network segmentation, not network layer isolation for applications.
- B. VLANs provide Layer 2 segmentation but share the same routing table at Layer 3; they do not offer complete routing table isolation.
- D. VXLAN extends Layer 2 segments over a Layer 3 network but doesn't inherently provide separate routing tables on a single device like VRFs.
Virtual Routing and Forwarding (VRF)
A network virtualization technology that creates multiple independent routing and forwarding tables within a single router or switch, enabling complete Layer 3 isolation.
- Each VRF acts as a separate virtual router.
- Provides complete isolation of routing tables and forwarding instances.
- Allows overlapping IP addresses between different VRFs.
Memory trick: VLANs divide LAN, VRFs divide Routers.