Overlay Versus Underlay Networks JN0-281 Practice Questions (Page 5)

Questions 21–25

1. 21foundation · easy

   Which benefit does an overlay network provide in a multi-tenant data center?

   • AIt removes the need for IP addressing on the underlay.
   • BIt guarantees higher bandwidth than the underlay can provide.
   • CIt allows multiple tenants to share the same physical network while keeping their traffic isolated.
   • DIt eliminates the need for physical switches entirely.
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2. 22expert · hard

   A network architect is designing the underlay for a large data center that will host a VXLAN overlay. The design must support both east-west and north-south traffic efficiently. The architect is considering a spine-and-leaf topology. What is the primary advantage of this topology for the underlay?

   • AIt simplifies the underlay by requiring only a single path between any two leaf switches.
   • BIt eliminates the need for IP routing in the underlay by providing Layer 2 connectivity between all switches.
   • CIt provides a low-latency, high-bandwidth, non-blocking fabric with multiple equal-cost paths for east-west traffic.
   • DIt reduces the number of switches required compared to a traditional three-tier design.
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4. 23application · medium

   A university is setting up a research cluster for high-performance computing (HPC). The applications require low latency and high throughput, and the workloads are not virtualized. The network team is deciding between an overlay and an underlay approach. Which approach is most appropriate for this use case?

   • AUse a VXLAN overlay to provide flexibility and scalability for the HPC workloads.
   • BUse a mix of overlay and underlay to provide both performance and flexibility.
   • CUse a traditional three-tier network with VLANs to segment the HPC traffic.
   • DUse a dedicated underlay network with high-bandwidth, low-latency physical connections.
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5. 24application · medium

   A data center is deploying a VXLAN overlay. The underlay uses OSPF as the routing protocol. The network team is concerned about the convergence time of the underlay in the event of a link failure. Which underlay characteristic is most important to ensure fast convergence?

   • AThe underlay must be a Layer 2 network to avoid routing convergence delays.
   • BThe underlay must have redundant paths and fast failover mechanisms, such as BFD, to minimize convergence time.
   • CThe underlay must use static routes to avoid the overhead of dynamic routing protocols.
   • DThe underlay must be configured with a single path to simplify routing and reduce convergence time.
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6. 25application · medium

   A service provider is evaluating network architectures for a new cloud platform. The goal is to support a large number of tenants with isolated virtual networks while minimizing the complexity of physical network changes when tenants are added or moved. Which architectural approach best meets this goal?

   • ABuild a flat Layer 2 network using VLANs to provide tenant isolation across the entire data center.
   • BUse a single routed network with tenant isolation provided by access control lists on each router.
   • CDeploy an overlay network using VXLAN to create logical tenant segments that are independent of the physical topology.
   • DImplement a dedicated physical network per tenant to ensure complete isolation.
   Reveal Solution Discussion Select an answer first