Implementing and Operating Cisco Enterprise Network Core Technologies (ENCOR) v1.2VirtualizationMedium
A cloud provider offers multi-tenant services where each tenant requires a dedicated virtual routing instance that is entirely isolated from other tenants, including separate routing tables, interfaces, and forwarding information bases. The provider uses Cisco IOS XE routers. Which feature should be configured to achieve this level of isolation?
- AVRF-Lite
- BPBR (Policy-Based Routing)
- CNAT (Network Address Translation)
- DEEM (Embedded Event Manager)
Show answer & explanationAnswer & explanation
Correct answer: A. VRF-Lite
VRF-Lite (Virtual Routing and Forwarding Lite) on Cisco IOS XE routers allows the creation of multiple independent routing and forwarding instances within a single physical router. Each VRF instance has its own routing table, forwarding information base (FIB), and can be associated with specific interfaces, providing complete Layer 3 isolation for multi-tenant environments.
Why the other options are wrong
- B. PBR modifies forwarding decisions based on policies but does not create separate routing instances or provide multi-tenant isolation.
- C. NAT translates IP addresses but does not provide routing isolation between tenants.
- D. EEM is for automating tasks and responding to network events, not for network virtualization.
VRF-Lite for Multi-tenancy
A feature on Cisco routers that enables logical separation of routing and forwarding functions, allowing multiple independent routing instances to coexist on one physical device.
- Each VRF maintains its own routing table, FIB, and connected interfaces.
- Provides Layer 3 isolation for multi-tenant environments.
- Does not require MPLS, making it 'Lite'.
Memory trick: VRF-Lite: Virtual Routes for isolated tenants without MPLS.