CCDE: Cisco Certified Design Expert (Practical) — Question 69

Sometimes SDN leverages various overlay networking technologies to create layer(s) of network abstraction. What describes an overlay network?

Answer options

• A. It transmits packets that traverse over network devices like switches and routers
• B. It encapsulates packets at source and destination, which incurs additional overhead
• C. Packet delivery and reliability occurs at Layer 3 and Layer 4
• D. It is responsible for the delivery of packets; NAT- or VRF-based segregation is required

Correct answer: B

Explanation

The correct answer is B because an overlay network encapsulates packets, which adds some overhead due to the extra headers involved. Option A is incorrect as it describes basic packet transmission without the encapsulation aspect of overlay networks. Option C is not accurate because it does not specifically address the unique attributes of overlay networks. Option D misrepresents the role of an overlay network, which does not inherently require NAT or VRF for packet delivery.