400-007 Exam Dumps - Cisco CCDE v3.0 Questions and Answers

Comprehensive and Detailed Explanation:

A: Data sovereignty refers to legal and regulatory policies that require data to reside within a particular country and be subject to its laws. This impacts how cloud and hybrid architectures are designed and which regions can be used for storage or compute.

Other options:

B: “Data rationality” is not a recognized regulatory or legal term.

C: Data inheritance refers to metadata or permission models, not legal jurisdiction.

D: Data replication is a technical process, not a legal requirement.

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In this architecture:

A secure web proxy is introduced to inspect and filter all web (HTTP/HTTPS) traffic.

Remaining traffic (non-web) must pass through an NGFW with IPS capabilities.

Both the web proxy and NGFW reside between the collapsed distribution/core and internet edge.

To enforce that all web traffic is directed to the proxy appliance for inspection and non-web traffic follows its usual path to the NGFW:

A. Policy-Based Routing (PBR) on the Collapsed Core

This allows traffic classification based on destination port (e.g., TCP 80/443) and selectively reroutes web traffic to the proxy. Non-web traffic continues toward the NGFW. PBR is essential here because traditional routing (based only on destination IP) would not differentiate between traffic types.

D. Static Routing on the Appliance

The proxy appliance must return the traffic back toward the NGFW for final processing and internet egress. This is typically achieved using static routes on the proxy device, ensuring the return path sends packets back to the correct firewall interface for consistent inspection.

❌B. Policy-based routing on the internet edge: Not applicable here, as rerouting must occur closer to the source (collapsed core), before traffic reaches the internet edge.

❌C. Policy-based routing on firewalls: This adds unnecessary complexity. Firewalls should focus on enforcing security policies, not traffic redirection logic in this scenario.

This approach adheres to CCDE v3.1 best practices by separating policy enforcement functions and enabling scalable, deterministic traffic flow through layered security appliances.

Comprehensive and Detailed Explanation From Exact Extract of Design Expert (CCDE)

Summarization reduces control plane state by abstracting detailed route information. As packets move further away from the destination subnet, the network advertises summarized prefixes instead of individual host or subnet routes, minimizing control plane overhead and routing table size. This helps scale large networks and improves convergence times.

While aggregation and summarization are related, summarization specifically refers to the propagation of route prefixes and their abstraction — making it the precise fit for this question.

D: CWDM (Coarse Wavelength Division Multiplexing) shares parts of the same optical transmission window (1260–1625 nm) as DWDM but uses wider spacing between channels (typically 20 nm apart).

E: CWDM typically uses passive devices (multiplexers and demultiplexers) that require no electrical power, making deployment cost-effective.

Incorrect Options:

A: CWDM is better suited for shorter distances (up to ~80 km) and doesn't typically use optical amplifiers (EDFA). DWDM is better for long-haul with amplification.

B: 850 nm is used in multimode fiber systems (not CWDM).

C: CWDM supports up to 18 channels; DWDM supports up to 32 or more.

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The design requires scalability, centralized credential management, device independence, and role-based access:

B (Central authentication directory): A centralized directory (such as Active Directory, RADIUS, or LDAP) allows the VPN solution to leverage existing user credentials, support role-based access control, and scale easily.

F (SSL VPN): Provides remote access VPN services that support a variety of client devices, including unmanaged or personal devices, without requiring device certificates. SSL VPN is well-suited for scenarios where users may not always use the same device.

Other options explained:

A: Local usernames/passwords do not scale to thousands of users and lack centralized policy control.

C/E: Certificates would require device management and may not be feasible if users switch devices.

D: IPsec VPN can work, but typically requires more complex client configuration and may not support flexible device usage as well as SSL VPN.

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Comprehensive and Detailed Explanation:

To reduce oscillation and improve resiliency:

D: Increasing unequal-cost multipath (UCMP) paths allows the routing protocol to load-share over more than one path, preventing traffic congestion from oscillating between nodes.

E: Dual links to each site improve bandwidth and failover options, reducing reliance on overloaded peers.

Other options:

A: Increasing redundant paths may worsen convergence complexity and doesn't solve oscillation.

B: Removing inter-spoke links reduces redundancy.

C: Increasing convergence timers delays recovery and stability.

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C (Lack of visibility and tracking): In cloud-native environments, organizations often struggle with monitoring and tracking workloads across dynamic, distributed, and multi-tenant architectures. Traditional visibility tools may not fully cover cloud-native assets like containers, serverless functions, or microservices, making it harder to detect threats and enforce policies.

D (Increased attack surface): Cloud-native architectures introduce many additional components—APIs, microservices, third-party integrations, and distributed data—which all expand the organization's overall attack surface. More entry points for attackers create additional security challenges compared to traditional on-prem environments.

Other options explained:

A: User roles can be managed with proper IAM systems.

B: Polymorphism refers to code behavior in programming, not a core security challenge in cloud-native design.

E: Credential validation is part of basic access control but not a top cloud-native challenge compared to visibility and attack surface expansion.

The goal is to prevent AS 111 from being used as a transit AS.

The most effective method is to use an AS path access list to filter outbound BGP advertisements, allowing only prefixes originated from AS 111 (AS path contains only AS 111).

This ensures AS 111 only advertises its own prefixes and does not forward third-party prefixes between providers.

Why other options are incorrect:

A: AS-set is used for aggregation, not for transit prevention.

B: Local preference controls outbound path selection, not advertisement or transit.

D: Prefix list on inbound filters received prefixes, but does not prevent transit.

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B (Enable phone VPN authentication based on end-user username and password):When legacy devices don’t support certificate-based authentication, fallback to username/password provides a temporary workaround while maintaining PCI compliance, assuming strong credentials and secure tunnels are used.

Other options explained:

A: Immediate hardware replacement may not be feasible.

C: TLS 1.0 fallback violates PCI standards, which prohibit deprecated protocols.

D: Clear text authentication is non-compliant with PCI requirements.

Inbound traffic engineering is best controlled by manipulating how external ASes view your routes.

AS path prepending on the 91.7.0.0/16 prefix towards AS 200 makes AS 500 prefer the less-prepended path through AS 100.

This allows granular inbound control for that specific prefix while leaving the rest of the traffic unchanged.

Why other options are incorrect:

B: Extended community is not used for direct inbound path manipulation.

C: Local preference affects outbound traffic, not inbound path selection by remote ASes.

D: MED is only compared between the same AS; it won't affect AS 500's choice.

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