300-420 Exam Dumps : Designing Cisco Enterprise Networks (ENSLD) v1.1

The primary capability of IaaS in this question is elastic scaling: the ability to increase or decrease infrastructure resources based on demand. In Infrastructure as a Service, the provider offers compute, storage, and network resources as an on-demand service, while the customer deploys operating systems and applications on top of that infrastructure. Cisco cloud material describes this model as providing scalable IT capacity without requiring the organization to own all physical assets. Option C is the best answer because dynamic capacity adjustment is a fundamental cloud capability and a major reason enterprises choose IaaS for variable workloads. Option B is a valid business benefit because consumption-based billing can reduce cost, but the question asks for a primary capability, not the pricing model. Option D describes automation and orchestration, which support cloud operations but are not the specific capability being tested. Option A is closer to hybrid-cloud workload mobility and is not guaranteed by IaaS alone. Reference topics: cloud service models, IaaS, elasticity, scalable compute, on-demand resource provisioning.

TLOC extension is the Cisco SD-WAN mechanism that allows a WAN Edge router without direct access to a transport to reach that transport through another WAN Edge router at the same site. Cisco describes TLOC extension as a redundancy feature in SD-WAN networks. In the question, the WAN Edge router is connected to an MPLS transport link, but Internet access is available through another WAN Edge device. With TLOC extension, the MPLS-only edge can extend traffic through the peer router toward the Internet transport, allowing the site to use multiple transports without requiring every edge router to have a physical connection to every circuit. OMP can advertise routes and TLOCs, but OMP alone does not create physical Internet access for a router attached only to MPLS. Requiring a local 4G/5G or Internet circuit on the same router is not necessary when TLOC extension is part of the design. An MPLS extranet is also not the normal SD-WAN solution for Internet transport reachability. Therefore, TLOC extension is the correct design method.

The correct BGP design is to attach the well-known No-Export community to the prefixes that should not be advertised beyond the service provider boundary. Cisco BGP communities are policy attributes that allow routes to carry instructions or classifications across BGP peers. The No-Export community tells a receiving BGP speaker not to advertise the route outside its confederation or autonomous system. That behavior is exactly what is needed when branch prefixes may be exchanged with the provider but must not be propagated to the public Internet. The No-Advertise community is stronger: it prevents the route from being advertised to any BGP peer, which may block reachability even where the provider still needs to know the route. NOPEER is used for route-server or peering policy control and is not the clean answer for excluding branch prefixes from Internet propagation. Setting a generic “Internet community” is not a standard solution by itself. The architect should also ensure that outbound prefix filters and provider-side community support are documented in the service agreement. Reference topics: BGP communities, No-Export, No-Advertise, provider edge filtering, Internet route policy.