N10-009 Question 124
Single answerA retail company is replacing traditional branch routers with an SD-WAN solution across 60 stores. Each store has a broadband Internet circuit and either LTE or MPLS as a secondary WAN link. The network team wants new appliances shipped directly to stores, where nontechnical staff can plug them in and have them automatically receive the correct configuration. The company also wants voice and payment traffic to prefer the best-performing path at any given time, regardless of whether that path is broadband, LTE, or MPLS. Finally, security and traffic rules must be created once and enforced consistently across all branches from a single interface. Which combination of SD-WAN capabilities best meets these requirements?
- A
Zero-touch provisioning, application-aware routing, transport-agnostic connectivity, and central policy management
- B
Static route redistribution, VLAN trunking, and local device-by-device ACL configuration
- C
Port mirroring, link aggregation, and out-of-band management
- D
Quality of Service only, with manual branch staging before shipment
Show answer and explanation
Correct answer: A
Explanation
The best answer is the combination of zero-touch provisioning, application-aware routing, transport-agnostic connectivity, and central policy management. These are core SD-WAN characteristics used in real deployments to simplify branch rollout and improve application performance. Zero-touch provisioning is a standard SD-WAN operational model in which an edge device contacts an orchestrator or controller after basic network access is available, authenticates, and downloads its configuration automatically. Application-aware capabilities allow traffic to be classified and forwarded according to business policy and measured link health, which is especially important for delay-sensitive applications such as voice and transactional payment systems. Transport agnostic means the SD-WAN overlay can run across diverse underlay networks, including broadband Internet, MPLS, and cellular, while applying the same higher-level policy logic. Central policy management aligns with industry best practice by reducing configuration drift and enabling consistent security and traffic handling across all branches. These concepts are broadly reflected in vendor SD-WAN architectures and in common networking guidance that emphasizes centralized orchestration, intent-based policy, and dynamic path selection for branch WAN modernization.
- A. Correct.
Correct. Zero-touch provisioning allows branch appliances to be sent directly to stores and automatically onboard to the controller with minimal local effort. Application-aware routing enables the SD-WAN to identify traffic such as voice or payment applications and steer it based on business intent and real-time link conditions like latency, loss, and jitter. Transport-agnostic connectivity means the overlay can use different underlay links, such as broadband, LTE, and MPLS, without requiring the policy design to depend on a single carrier type. Central policy management lets administrators define security and traffic policies once in a controller or orchestrator and push them consistently to all branch sites.
- B. Incorrect.
Incorrect. Static route redistribution and VLAN trunking are traditional networking functions, but they do not address automatic branch onboarding, dynamic path selection based on applications, or centralized SD-WAN policy control. Local device-by-device ACL configuration is the opposite of central policy management and creates operational inconsistency across many sites.
- C. Incorrect.
Incorrect. Port mirroring is used for traffic analysis, link aggregation combines interfaces for bandwidth or redundancy, and out-of-band management provides separate management access. These features may be useful in some environments, but they do not solve the stated branch deployment, application-aware path selection, or centralized SD-WAN policy requirements.
- D. Incorrect.
Incorrect. QoS can prioritize traffic classes, but by itself it does not provide application-aware path steering across multiple WAN transports based on changing circuit performance. Manual branch staging also conflicts with the requirement to ship devices directly to stores for nontechnical staff to install. This option addresses only a small portion of the scenario and misses key SD-WAN capabilities.