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Dual DMVPN with EIGRP routing is the correct solution because the requirements call for secure public-internet connectivity, redundant paths, automatic path selection, multicast support, and minimal remote-site configuration. DMVPN builds dynamic multipoint GRE tunnels protected by IPsec, allowing spoke sites to communicate securely through the public internet while supporting routing protocols and multicast over GRE. A dual DMVPN design provides redundancy through separate hubs, transports, or tunnel clouds, so a spoke can continue operating if one path fails. EIGRP can calculate alternate paths and react to metric changes, supporting automatic path selection based on failure and quality when engineered correctly. MPLS with BGP does not meet the public-internet and encryption requirements by itself. A full mesh of IPsec tunnels with OSPF or IS-IS would increase configuration complexity at every remote site and does not scale as well. DMVPN is specifically built to simplify deployment of secure, scalable, multipoint branch VPNs. Reference topics: DMVPN, IPsec, mGRE, EIGRP over DMVPN, WAN redundancy, multicast over GRE.

The SD-Access control-plane node performs the LISP Map-Server and Map-Resolver functions. Cisco SD-Access uses LISP in the control plane to maintain mappings between endpoint identifiers and routing locators. Fabric edge nodes discover local endpoints and register them with the control-plane node. When a destination endpoint is not known locally, a fabric node queries the control-plane node, which resolves the endpoint location and returns the locator information needed for VXLAN forwarding through the fabric. This is why the control-plane node is the correct answer. A fabric edge node connects endpoints, provides the anycast gateway, encapsulates and decapsulates user traffic, and registers endpoints. A border node connects the fabric to external networks. An intermediate node simply transports routed underlay traffic between fabric nodes and does not hold endpoint mappings. In design terms, control-plane placement and redundancy are critical because endpoint mobility, fabric forwarding lookup, and location resolution depend on stable Map-Server and Map-Resolver services. Reference topics: Cisco SD-Access control plane, LISP Map-Server, LISP Map-Resolver, EID-to-RLOC mapping, fabric edge registration.

This YANG mapping is based on how IETF, OpenConfig, and Cisco native models differ in portability and schema organization. IETF models are produced through the standards process and are appropriate when the same management structure is expected across vendors for common protocols. OpenConfig models are also vendor-neutral, but they are built around a consistent operational model used heavily for streaming telemetry and multivendor automation. Cisco native models mirror Cisco platform configuration more closely and expose device-specific capabilities that may not exist in common models. The selected answers keep those boundaries clear. This matters because a NETCONF or RESTCONF payload is validated against the YANG schema; a payload written for one model family cannot be assumed to work against another. In design terms, the model family should be selected after confirming device software release support, feature coverage, operational-state requirements, and vendor diversity. Open models give portability; native models give feature completeness. Reference topics: IETF YANG, OpenConfig YANG, Cisco native YANG, schema validation, automation model selection.

IntServ with RSVP is the correct model when an application must request a specific service level and receive guaranteed bandwidth or delay treatment. Cisco describes the Integrated Services model as a flow-based QoS architecture in which applications signal their resource requirements to the network. RSVP is the signaling protocol used to reserve resources along the path. This differs from DiffServ, which marks packets and applies per-hop behavior without creating per-flow reservations. The question states that the application can request a particular type of service to support its delay requirements and that bandwidth must be guaranteed. Those are classic IntServ and RSVP characteristics. DiffServ with DSCP is scalable and widely used in enterprise networks, but it cannot guarantee resources end to end unless every hop is engineered and provisioned accordingly. IntServ with DSCP is not the standard model because RSVP is the reservation mechanism. Reference topics: Integrated Services, RSVP, resource reservation, guaranteed service, QoS architecture, delay-sensitive applications.