Free Designing Cisco Enterprise Networks Practice Questions

Sample Practice Questions

Try these 10 sample questions from the Designing Cisco Enterprise Networks practice bank. Each includes the answer and explanation. Continue with the interactive practice above to review the full question set.

1. 1An IPv4 user VLAN needs 50 assignable host addresses. Which prefix uses the smallest address block that meets this requirement?

   1. A. /25
   2. B. /26
   3. C. /27
   4. D. /28

   Answer: B

   Explanation: Cisco states, "host ids of all zeros or all ones are not allowed" For this user subnet, usable capacity is 2^(32-prefix)-2. A /26 supplies 62 usable addresses; /27 and /28 supply too few, while /25 consumes more space.

   Reference: Configure IP Addresses and Unique Subnets for New Users — Understand Subnetting

2. 2HSRP router A has priority 120 and router B has priority 110. Both enable preemption. A must yield the gateway role when its tracked WAN route fails. Which decrement is sufficient to make B strictly higher priority?

   1. A. 5
   2. B. 10
   3. C. 15
   4. D. 0

   Answer: C

   Explanation: Cisco states, "If the specified object goes down, the HSRP priority is reduced." Subtracting 15 leaves A at 105, below B's 110. A decrement of 10 produces a tie rather than a strictly lower priority; 5 or 0 leaves A higher. Preemption lets B take over.

   Reference: Network Services Configuration Guide — Configuring HSRP — How Object Tracking Affects the Priority of an HSRP Device

3. 3An enterprise wants a provider-managed, peer-to-peer IP VPN in which the service provider participates in customer route distribution. Which WAN service fits?

   1. A. MPLS Layer 3 VPN
   2. B. Transparent point-to-point Ethernet
   3. C. Dark fiber with customer-only routing
   4. D. A Layer 2 VPLS service

   Answer: A

   Explanation: Cisco states, "outsource routing information to service providers" MPLS Layer 3 VPN is the peer-to-peer routed service. The transparent Layer 2 and dark-fiber alternatives leave Layer 3 routing to the enterprise rather than supplying provider-managed VPN route distribution.

   Reference: Traditional WAN Design Summary — Traditional WAN Best Practices > MPLS WAN Using Layer 3 VPN, p. 22

4. 4A large enterprise wants a small set of traffic classes and per-class resource allocation, avoiding per-flow reservation state in its core. Which QoS architecture matches this strategy?

   1. A. IntServ with a reservation for every flow.
   2. B. DiffServ with marked traffic aggregates.
   3. C. A separate RSVP session for every packet.
   4. D. Best-effort forwarding with no differentiated treatment.

   Answer: B

   Explanation: The source states, "allocates resources on a per-class basis" DiffServ groups traffic into classes and scales through aggregate treatment. Per-flow reservations use IntServ; RSVP does not establish a session per packet, and best effort does not supply differentiated class resources.

   Reference: Differentiated Services — DiffServ architecture model

5. 5Which YANG model ecosystem is primarily driven by network operators seeking a vendor-neutral model for configuration and telemetry?

   1. A. Cisco native YANG.
   2. B. IETF standards-track YANG.
   3. C. OpenConfig YANG.
   4. D. IEEE standards-based YANG.

   Answer: C

   Explanation: The source states, "OpenConfig is a network operator-driven YANG data model ecosystem" OpenConfig is the operator-driven ecosystem. IETF and IEEE provide standards-body models, while native models follow vendor implementations.

   Reference: Catalyst Programmability and Automation — Standards-based and third-party YANG > OpenConfig

6. 6A routed Ethernet link connects exactly two routers. Both support RFC 3021 and need only one IPv4 address each. Which prefix conserves the most addresses?

   1. A. /29
   2. B. /30
   3. C. /32
   4. D. /31

   Answer: D

   Explanation: Cisco states, "A 31-bit subnet mask allows for exactly two host addresses" A /31 meets the two-endpoint requirement without network and broadcast reservations. A /32 cannot number both endpoints; /29 and /30 consume more addresses.

   Reference: Configure IP Addresses and Unique Subnets for New Users — Special Subnets > 31-bit Subnets

7. 7Hosts in one VLAN must use one shared virtual gateway IP, while traffic is distributed across multiple gateways through different virtual MAC addresses. Which FHRP meets this design?

   1. A. GLBP
   2. B. HSRP
   3. C. VRRP
   4. D. HSRP for IPv6

   Answer: A

   Explanation: Cisco states, "a single virtual IP address and multiple virtual MAC addresses" GLBP supplies multiple active virtual forwarders for the shared IP. A single HSRP or VRRP group elects one active forwarding gateway rather than providing GLBP's host distribution across virtual MAC addresses.

   Reference: Network Services Configuration Guide — Configuring GLBP — Information About GLBP > GLBP overview

8. 8A WAN provider should appear transparent at Layer 3 while delivering Ethernet connectivity between sites. The enterprise will run and control all IP routing itself. Which service model fits?

   1. A. MPLS Layer 3 VPN with provider-managed routes.
   2. B. A provider-managed routed Internet VPN service.
   3. C. An Ethernet-access IP VPN in which provider PEs exchange the customer's IP routes.
   4. D. A Layer 2 WAN using VPLS or Metro Ethernet.

   Answer: D

   Explanation: Cisco states, "organization implements all Layer 3 routing" VPLS or Metro Ethernet as a Layer 2 WAN leaves IP routing to the enterprise. MPLS Layer 3 VPN, a provider-managed routed VPN, and an Ethernet-access service whose PEs exchange customer IP routes all place Layer 3 responsibility at the provider rather than delivering the requested Layer 3 transparency.

   Reference: Traditional WAN Design Summary — Traditional WAN Best Practices > Layer 2 WAN Using VPLS or Metro Ethernet, p. 25

9. 9An application requires explicit signaling of its per-flow QoS needs along the network path before beginning transmission with reserved resources. Which strategy provides this function?

   1. A. IntServ using RSVP signaling.
   2. B. DiffServ marking without reservation signaling.
   3. C. Best-effort FIFO forwarding without admission.
   4. D. A DSCP rewrite without resource reservation.

   Answer: A

   Explanation: The source states, "IntServ uses Resource Reservation Protocol (RSVP)" RSVP explicitly signals the application's needs and permits resource reservation along the path. Class marking, FIFO, or rewriting a header does not establish the requested per-flow reservation.

   Reference: Integrated Services — IntServ RSVP signaling

10. 10On IOS XE, which YANG model family generally offers the richest coverage of Cisco-specific configuration and operational features?

    1. A. Cisco native models.
    2. B. OpenConfig common models.
    3. C. IETF interface models.
    4. D. IEEE common models.

    Answer: A

    Explanation: The source states, "Cisco native data models are the most feature-rich" Native models follow Cisco features closely. Open and standards-based models serve common requirements and generally cover a subset; actual model support still depends on device and release.

    Reference: Catalyst Programmability and Automation — Who defines the YANG models?