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

A (BPDU Guard on access ports): Prevents accidental connection of switches or bridging devices on access ports, which could cause unexpected topology changes or loops.

C (Root Guard on aggregation switch downlinks): Ensures access switches cannot send superior BPDUs to challenge aggregation switch root status, maintaining predictable STP root placement.

Why other options are incorrect:

B: Aggregation downlinks are not normally configured with BPDU Guard (since they expect BPDUs from access switches).

D: Root guard on access ports is unnecessary as those ports should not participate in STP.

E: Edge port (Rapid STP concept) is good for faster convergence but doesn't address stability.

F: STP root and backup root election is important but not a specific STP feature — this is a design decision, not a stability feature.

Public cloud offers scalability, flexibility, and consumption-based pricing, which directly reduces capital expenditures (CAPEX) and minimizes operational burden (less IT staff needed for infrastructure maintenance).

Public cloud eliminates upfront hardware investments and shifts cost to predictable operational expenses.

Public cloud providers handle hardware maintenance, upgrades, and scalability, making it highly cost-effective for government agencies with fluctuating workloads.

Why other options are incorrect:

A: On-premises increases CAPEX and requires significant IT staff.

B: Private cloud reduces some OpEx but still requires infrastructure management and higher CAPEX.

D: Hybrid cloud increases complexity and operational costs.

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B (OSPF Type 1 external):Type 1 external routes include both the external cost (from redistribution) and the internal OSPF cost to the ASBR. This ensures accurate end-to-end metric calculation across domains.

Other options explained:

A: Type 2 external ignores internal OSPF cost, potentially creating suboptimal routing.

C/D: EIGRP doesn’t use OSPF metric types; redistribution into EIGRP uses EIGRP metrics.