Cisco Updated 400-007 Exam Questions and Answers by louise

B (Confidentiality):Protects data from unauthorized access or disclosure.

E (Integrity):Ensures data remains accurate and unaltered.

F (Availability):Ensures that data and systems are accessible when needed.

Other options explained:

A: Cryptography is a tool used to achieve confidentiality, integrity, or authentication, but it's not part of the CIA triad itself.

C/D: Authorization and identification are security processes, but not part of the core CIA triad.

PIM-SSM (Source-Specific Multicast) is optimized for multicast delivery directly via Shortest Path Tree (SPT) only.

SSM eliminates the need for shared trees (RPs), simplifies the control plane, and avoids rendezvous points altogether.

This design is highly scalable in multidomain and IPv6 environments, fully aligned with CCDE v3.1 best practices for modern multicast deployments.

Why other options are incorrect:

A: PIM-DM floods traffic initially, not SPT-based.

B: PIM-SM uses shared trees first and may switch to SPT later.

D: Bidir-PIM uses shared trees exclusively, not SPT.

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C. Fragment data packets: On slow WAN links, large data packets can delay small voice packets (serialization delay). Fragmentation ensures that voice packets are interleaved and not delayed behind large data frames (Link Fragmentation and Interleaving - LFI).

E. Prioritize voice packets: QoS mechanisms (LLQ, priority queuing) ensure that voice traffic is serviced first, reducing jitter and delay.

These are both critical QoS design principles for real-time application performance in constrained branch WAN scenarios, as outlined in CCDE v3.1.

Why other options are incorrect:

A: Increasing bandwidth may help but doesn’t address serialization or prioritization.

B: Memory upgrades do not directly improve voice quality.

D: Fiber upgrades do not address WAN-specific serialization or QoS.

A (Route Reflector design): Using R5 as a route reflector reduces the IBGP full-mesh requirement while maintaining route visibility between R1, R2 (edge) and R3, R4 (ABRs).

Internet routes can be redistributed into OSPF at the edge routers (R1, R2), allowing internal reachability while avoiding redistribution complexity on every router.

Why other options are incorrect:

B: Sub-AS designs (confederations) add unnecessary complexity for this scenario.

C: Full mesh IBGP is not scalable with increasing nodes.

D: Not using a route reflector would force full mesh IBGP.