400-007 Exam Dumps - Cisco Certified Design Expert (CCDE v3.1)

The SD-WAN architecture separates roles by function:

Orchestration Plane: Handles device lifecycle functions such as zero-touch provisioning (ZTP) and certificate distribution. It facilitates onboarding into the overlay securely and automatically.

Control Plane: Makes forwarding decisions and shares route and policy information.

Data Plane: Forwards packets.

Management Plane: Provides visibility, analytics, and template-based policy configuration.

Option A correctly identifies orchestration as the ZTP and bootstrapping component.

A soft failure refers to a condition where the network continues to operate, but performance or behavior is degraded in a way that is not immediately visible or detectable—this includes suboptimal routing, misconfigured protocols, or resource inefficiencies. These are harder to define and detect because they don't cause total outages but still impact user experience or service quality. In contrast, hard failures like outages (Option D) are more visible and measurable.

This aligns with CCDE v3.1’s guidance on resilience, observability, and performance-aware design, emphasizing proactive identification of non-fatal but service-impacting anomalies.

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D: Traditional three-tier architectures (access, distribution, and core layers) require that east-west traffic (between servers or pods in different access layers) traverse up to the distribution or core and then back down—introducing unnecessary hops and latency. This is a key design limitation addressed by spine-leaf and fabric architectures.

Other options:

A: Bandwidth may be sufficient but not optimally utilized due to suboptimal pathing.

B: Security is not inherently compromised by architecture, although microsegmentation is harder.

C: Three-tier architectures can scale, but less efficiently and not without trade-offs like latency and complexity.

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To support high-bandwidth, low-latency Layer 2 communication between DB Server 1 and DB Server 2, you must create a direct Layer 2 path between SW1 and SW2. Using REP (Resilient Ethernet Protocol) segments ensures loop-free Layer 2 operation without the drawbacks of STP convergence delays.

Option C is correct: Adding a third REP segment (Segment 3) directly between SW1 and SW2 isolates the traffic between the two DB servers and ensures deterministic behavior with fast convergence.

Option A (LACP with STP) introduces STP blocking and doesn’t align well with REP's control plane.

Option B and D: Overloading existing segments or splitting new links into existing REP segments does not offer the same direct path, bandwidth, or deterministic behavior.

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HIPAA requires integrity controls to prevent unauthorized data modification.

D (Technical integrity and transmission security): Ensures PHI data is protected against unauthorized alteration during storage and transmission.

This directly addresses the issue of data being altered without consent.

Why other options are incorrect:

A: Prevents unauthorized access but does not guarantee data integrity.

B: Administrative processes cover policies, not technical enforcement.

C: Focuses on physical device control, not data integrity.

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Loop Guardis designed to protect againstSTP loop conditionsthat may occur whenBPDUs are unexpectedly missingon a point-to-point link. This is especially relevant in cases where UDLD (Unidirectional Link Detection) might not detect the problem quickly enough. When BPDUs are absent, a switch might erroneously assume that the link is safe to forward, potentially leading to atemporary Layer 2 loop.

UsingLoop Guardensures that a port moves into aloop-inconsistentstate instead of forwarding traffic if BPDUs are missing, effectively stopping a loop before it forms. This makes it acomplementary mechanism to UDLD, which focuses on detecting unidirectional links at the physical layer, not STP control plane failures.

This recommendation aligns with CCDE v3.1 best practices forresilient Layer 2 designs, which emphasize using multiple mechanisms in tandem to proactively prevent failure conditions before traffic is impacted.

Why other options are incorrect:

A. Root Guard: Prevents an unauthorized switch from becoming the root bridge but doesn't protect against missing BPDUs.

B. BPDU Guard: Used mainly on access ports to prevent BPDU reception; not intended for core loop prevention.

D. BPDU Filtering: Suppresses BPDU exchange entirely, which increases loop risk and is not suited for loop mitigation.