Cisco 300-420 Bundle

That change concerns qos classification encrypted traffic, where Encryption hides much application payload from intermediate classifiers, so deep packet inspection may not see per-app content inside the tunnel. The reported issue instead stems from: Trusting unvalidated endpoint DSCP markings allows unauthorized traffic to consume preferential network resources.

That change concerns qos policing versus buffering behavior, where Policing enforces a rate by dropping or remarking excess packets, whereas shaping ordinarily smooths outbound bursts using buffers. In this question the necessary remedy is “Define an appropriate trust boundary and classify or remark traffic at access based on authenticated application and endpoint context”, which this alternative does not provide.

That change concerns diffserv versus intserv service model, where Per-flow IntServ state scales differently from aggregated DiffServ classes and can become operationally expensive for large multi-site deployments. The observed condition is a user-controlled workstation marks all outbound bulk backup packets as expedited forwarding, causing voice queues to saturate during office hours; this mechanism addresses another problem.

Bandwidth alone does not determine application suitability when propagation delay and jitter exceed interactive service limits. “Choose appropriate low-latency WAN transport and QoS treatment, evaluating cost, resilience and route diversity” would remedy that alternative situation, but it would not correct the present issue: multihoming and address translation must account for both directions; outbound route changes alone may not preserve return paths.

“Size redundant WAN capacity for failure-state critical loads or design explicit congestion and traffic-class degradation policy” is the supported response when n-minus-one operation cannot carry combined load if each remaining link lacks spare capacity or business traffic prioritization. Here the decisive response is “Design consistent BGP advertisement, NAT and routing failover so return flows follow the reachable secondary path”, so that different intervention does not meet the stated requirement.

The orchestration function helps WAN edges discover and authenticate to the fabric but should not be placed in the regular data forwarding path. “Design supported Catalyst SD-WAN orchestrator reachability and certificate trust separately from data-plane transport tunnels” applies to that other condition. The reported evidence is an enterprise tests its secondary Internet link and sees outbound connectivity, but return traffic continues toward a withdrawn primary public prefix; this alternative would address the wrong dependency.

A per-VLAN spanning-tree model scales protocol state with VLAN count and may become less efficient than suitable aggregated instances. “Assess MST or Layer 3 access boundaries against actual traffic steering and availability requirements” would remedy that alternative situation, but it would not correct the present issue: MST region membership requires consistent region identifier, revision and VLAN mapping rather than matching only some VLAN names.

“Enable Root Guard on appropriate downstream designated ports and keep intended root roles explicit” is the supported response when superior BPDUs on an untrusted downstream link can alter STP root selection unless the boundary is protected. Here the decisive response is “Align approved MST region configuration and verify boundary ports and per-instance root placement”, so that different intervention does not meet the stated requirement.

A non-designated STP port losing expected control messages can create a loop if it incorrectly assumes the superior path vanished. “Use Loop Guard on appropriate non-edge STP links and deploy complementary unidirectional link detection where supported” applies to that other condition. The reported evidence is two campus buildings should share one MST region but have different region names or VLAN-to-instance maps, unexpectedly changing STP behavior at the boundary; this alternative would address the wrong dependency.

That change concerns wan circuit oversubscription under failover, where N-minus-one operation cannot carry combined load if each remaining link lacks spare capacity or business traffic prioritization. The reported issue instead stems from: The orchestration function helps WAN edges discover and authenticate to the fabric but should not be placed in the regular data forwarding path.

That change concerns hybrid wan internet mpls policy separation, where A hybrid WAN needs explicit route and security decisions because reachability alone does not guarantee sensitive traffic uses approved paths. In this question the necessary remedy is “Design supported Catalyst SD-WAN orchestrator reachability and certificate trust separately from data-plane transport tunnels”, which this alternative does not provide.

That change concerns wan path latency versus bandwidth choice, where Bandwidth alone does not determine application suitability when propagation delay and jitter exceed interactive service limits. The observed condition is a design document treats Cisco SD-WAN orchestration as the same component that carries every branch's user payload rather than enabling secure device discovery; this mechanism addresses another problem.

A totally stubby or regular stub area cannot originate external LSAs through an internal ASBR in the required manner. “Design a supported NSSA with correct Type 7 origination and ABR translation handling where needed” would remedy that alternative situation, but it would not correct the present issue: a fragmented area-address plan and missing ABR inter-area summarization cause avoidable detailed LSAs to propagate.

“Select E1 or E2 route treatment to reflect the required exit preference, testing both external and internal metrics” is the supported response when external Type 2 cost behavior does not account for internal cost in the same way as Type 1 when external metrics differ. Here the decisive response is “Allocate summarizable ranges and apply appropriate ABR area range configuration with complete component-route validation”, so that different intervention does not meet the stated requirement.

OSPF hierarchical inter-area connectivity depends on a stable backbone design and resilient area border connectivity. “Design redundant ABRs with valid backbone area connectivity and deterministic cost preferences for inter-area paths” applies to that other condition. The reported evidence is dozens of contiguous branch prefixes are flooded individually into the OSPF backbone after a regional restructuring, increasing LSDB churn; this alternative would address the wrong dependency.

Logical dual-circuit contracts may share a physical access path and suffer a common-cause outage. “Request physical route-diversity evidence and test failover rather than counting only interface numbers” would remedy that alternative situation, but it would not correct the present issue: GRE provides encapsulation for multiple protocols but does not itself encrypt or authenticate payload confidentiality.

“Document cloud provider port limits, routing policies and redundancy across independent interconnect facilities” is the supported response when an encrypted Internet overlay does not provide the same private carrier connectivity, SLA and traffic-engineering options as a qualified dedicated cloud circuit. Here the decisive response is “Separate tunnel encapsulation requirements from cryptographic protection during design reviews”, so that different intervention does not meet the stated requirement.

Dynamic spoke resolution needs correct NHRP network ID, authentication, hub mapping and reachable tunnel source rather than only a live Internet connection. “Check dynamic public IP and NAT dependencies during DMVPN branch modem replacements” applies to that other condition. The reported evidence is an architect proposes plain GRE between remote branches to carry multicast routing updates and claims GRE alone satisfies corporate confidentiality requirements; this alternative would address the wrong dependency.

That change concerns BGP route reflector cluster design, where Conventional iBGP full mesh grows quadratically and becomes costly to configure, observe and recover. The reported issue instead stems from: Unbounded EIGRP query scope and nontransit spokes can prolong active route computation across a large topology.

That change concerns is-is adjacency authentication design, where An unprotected adjacency trust boundary can admit unauthorized IS-IS control messages into a routing domain. In this question the necessary remedy is “Declare eligible nontransit branches as EIGRP stubs and summarize at appropriate aggregation points with verified alternate paths”, which this alternative does not provide.

That change concerns is-is dual-stack address-family strategy, where Protocol adjacency and IPv4 routes do not alone establish correct IPv6 reachability, interface addressing or address-family support. The observed condition is a large hub-and-spoke EIGRP deployment sends queries into hundreds of branch routers during a core route failure, increasing convergence delay; this mechanism addresses another problem.

Fabric overlay encapsulation adds overhead beyond ordinary IP reachability and depends on a healthy L3 underlay. “Provide resilient IP underlay reachability and adequate end-to-end MTU for supported fabric encapsulation” would remedy that alternative situation, but it would not correct the present issue: fabric control-plane endpoint-to-location mapping must reflect movement and be consistent with current host registration.

“Design overlay forwarding paths with validated VXLAN reachability, fabric edge encapsulation and proper transport MTU” is the supported response when a fabric control plane supplies locator information, while the data plane uses supported VXLAN encapsulation to carry endpoint traffic. Here the decisive response is “Use supported redundant LISP control-plane nodes and verify endpoint registration and mapping refresh behavior”, so that different intervention does not meet the stated requirement.

Ordinary underlay reachability does not assign endpoint onboarding and VXLAN edge functions to a nonfabric access device. “Provision eligible access devices as supported fabric edge nodes and verify host onboarding and virtual network assignments” applies to that other condition. The reported evidence is a fabric edge learns an endpoint address but forwards to an old location after the endpoint moves between buildings because its mapping data is stale; this alternative would address the wrong dependency.

That change concerns gnmi subscribe and grpc transport, where gNMI is a model-driven management interface commonly using gRPC streaming and structured path/value messages rather than a generic webpage. The reported issue instead stems from: Traditional centralized route topology can add delay and consume backbone capacity even when local cloud on-ramp options are available.

That change concerns mpls direct cloud provider integration, where Private transport does not automatically enforce tenant segmentation or prevent unintended route exchange into cloud environments. In this question the necessary remedy is “Design supported cloud on-ramp or cloud gateway integration with controlled routing, identity and service security policy”, which this alternative does not provide.

That change concerns telemetry certificate mutual authentication, where TLS mutual authentication depends on valid identity and trust configuration, independent of basic network reachability. The observed condition is an enterprise uses SD-WAN at branches and wants direct low-latency cloud access, but cloud-hosted routes still hairpin through a remote data center; this mechanism addresses another problem.

Local preference is not exported between autonomous systems, so changing it cannot directly govern external networks' inbound selection. “Avoid promising deterministic global inbound routing from prepends, and test provider-specific policy interactions” would remedy that alternative situation, but it would not correct the present issue: IBGP typically preserves the external next hop, which must be reachable through the internal routing infrastructure.

“Test reflection path diversity and redundant reflector failure modes before retiring full-mesh peers” is the supported response when conventional iBGP full mesh grows quadratically and becomes costly to configure, observe and recover. Here the decisive response is “Verify both BGP control-plane route presence and IGP next-hop resolution in every edge design”, so that different intervention does not meet the stated requirement.

AS-path prepending mainly affects remote path selection; outbound path preference within the local AS is commonly controlled with local preference. “Separate inbound and outbound traffic-engineering objectives in BGP policy design documentation” applies to that other condition. The reported evidence is an edge router shares eBGP-learned routes with internal iBGP peers, but remote clients cannot resolve the unchanged external next-hop address; this alternative would address the wrong dependency.

An SVI routed ACL does not necessarily inspect intra-VLAN switched frames that never reach Layer 3 forwarding. “Test actual Layer 2 forwarding paths before certifying an SVI-only rule as local east-west isolation” would remedy that alternative situation, but it would not correct the present issue: bidirectional multipoint redistribution without route tagging or authoritative direction can reintroduce routes into their source protocol.

“Set explicit maximum Layer 2 failure domains during new-building network approvals” is the supported response when extending Layer 2 broadly across campus buildings increases loop, convergence and failure-domain exposure. Here the decisive response is “Validate tags and filtering under loss of either redistribution border router”, so that different intervention does not meet the stated requirement.

A common routing instance cannot enforce independent overlapping IP destinations and controlled route exposure by itself. “Require security approval and route-leak testing for every campus shared-services exception” applies to that other condition. The reported evidence is two campus cores exchange OSPF and EIGRP routes across two border routers and route entries recirculate until suboptimal paths appear; this alternative would address the wrong dependency.