An engineer has been asked to purpose a solution for a campus network that offers the capability to create multiple Layer 3 virtual networks. Each network must have its own addressing structure and routing table for data forwarding. The proposed design must be scalable to support a high number of virtual networks allowing simple configuration and management with minimal administrative overhead.
Which technology does the engineer recommend?
A . hop-by-hop VRF-Lite
B . multihop IPsec tunneling
C . multihop MPLS core
D . hop-by-hop easy virtual network
Answer: D
Explanation:
Hop-by-hop easy virtual network (EVN) based: Hop-by-hop VRF-lite is manageable for networks with fewer numbers of virtual networks and fewer numbers of hops in a virtual network path.
However, when the number of logical networks (virtual/tenants) increases, there will be a high degree of operational complexity to create and configure the interface or subinterface per VN.
EVN provides the same benefits for guaranteeing traffic separation with more simplified operations. In other words, EVN builds on VRF-Lite concepts and capabilities and provides additional benefits, including the following:
EVN offers better end-to-end VN scalability compared to the classic hop-by-hop 802.1Q-based solution.
EVN offers simplified configuration and management.
EVN offers the capability to provision shared services among different logical groups.
As illustrated in Figure 1-15, with the EVN path, you can achieve isolation by using a unique tag for each VN. This tag is referred to as VNET tag. Each VN carries over a virtual network the same tag value that was assigned by a network administrator.
Based on that, EVN-capable devices along the path will use these tags to ensure endto- end traffic isolation among different VNs. With this approach, the dependency on the classical (802.1Q based) physical or logical interfaces to provide traffic separation is eliminated.
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