Cisco Updated 400-007 Exam Questions and Answers by saul

In OSPF, a ring topology typically converges more slowly because:

Link failures can create longer SPF recalculations as alternate paths are fewer.

Only one alternate path usually exists for each link failure, extending the time needed for failure detection and SPF recalculation.

CCDE v3.1 stresses that designs like full mesh or triangulated topologies provide faster convergence due to multiple available alternate paths, which reduce SPF computation complexity.

Why other options are incorrect:

A, D, E: These topologies provide multiple paths.

B: Full mesh offers immediate redundancy for any failure.

—

In addition to business requirements, network architects must also account for non-business constraints such as legal, regulatory, and industry compliance. These may include standards like GDPR, HIPAA, PCI-DSS, or country-specific data sovereignty and retention laws.

Compliance is not typically driven by direct business value but by external mandates that influence how the network must be designed, implemented, and operated. Ignoring compliance requirements can result in significant legal or financial penalties and is therefore a core component of any responsible network design.

Other options such as:

A. Location — may impact design (e.g., latency, availability), but it is often categorized as a technical or logistical consideration.

B. Cost — is a business constraint.

C. Time — is considered a project or delivery constraint, also typically business-driven.

In 802.1d STP, convergence is influenced by hello timer, max_age, and forward_delay.

While hello_timer typically remains at 2 seconds, lowering max_age (default 20s) and forward_delay (default 15s) can speed up convergence.

Forward_delay controls the time spent in listening and learning states; max_age determines how long a BPDU is considered valid before recalculating topology.

Why other options are incorrect:

A, B, D: These timers (transit_delay, bpdu_delay, maximum_transmission_halt_delay) are not directly adjustable parameters in 802.1d implementations.

—

Bidirectional Forwarding Detection (BFD) provides fast failure detection independent of routing protocols. It can be integrated with multiple protocols to accelerate convergence:

A: IS-IS supports BFD for fast hello processing.

B: BFD can track static routes via routing tracking features.

D: EIGRP supports BFD for link failure detection.

E: BGP supports BFD for rapid session teardown.

Why option C is incorrect:

C: RIP does not natively support BFD integration.

—