CCNA IP Routing Practice Test 3 — 15 Questions

Question 1

Which statement best explains why BGP path-vector behavior is often presented as different from OSPF link-state behavior?

Accepted Answer

Because OSPF is an interior link-state protocol, while BGP is a path-vector protocol associated with interdomain routing.. The two protocols are presented differently because they approach route exchange and path reasoning in different ways. In practical terms, OSPF is an interior link-state protocol associated with topology awareness inside a routing domain, while BGP is associated with exchanging reachability and path information across autonomous-system boundaries.

At CCNA level, the goal is to understand that these protocols serve different scopes and models of routing.

Answer

Because BGP is only for Layer 2 switching and OSPF is only for wireless networks.

Answer

Because OSPF has no metrics and BGP always uses STP cost.

Answer

Because BGP and OSPF are both DHCP extensions.

Question 2

Which statement best describes the difference between PAP and CHAP in PPP authentication at a basic level?

Accepted Answer

CHAP is generally considered stronger than PAP for PPP authentication.. At a basic level, CHAP is generally considered stronger than PAP because it does not rely on the same simple approach to credential exchange. In practical terms, CCNA learners should recognize that PPP supports authentication options and that CHAP is typically the more security-conscious choice compared with PAP.

The point is not to memorize every exchange sequence, but to understand that the two methods are not equally strong.

Answer

PAP is required before CHAP can operate.

Answer

CHAP is used only on wireless guest SSIDs.

Answer

PAP and CHAP are both STP guard features.

Question 3

A router has these routes in its routing table:

O 172.16.0.0/16
O 172.16.20.0/24
S 172.16.20.128/25

A packet destined for 172.16.20.200 arrives. Which route will the router use?

Accepted Answer

172.16.20.128/25. Routers choose the most specific matching route. The destination 172.16.20.200 falls within 172.16.20.128/25, so that static route is used even though broader matches also exist.

Answer

172.16.0.0/16

Answer

172.16.20.0/24

Answer

The default route

Question 4

Match each routing term to its description.

Accepted Answer

System routes: Default routes automatically created by the system.. System routes are default routes automatically created by the system to manage traffic within a network, such as within a virtual network and to the internet. User-defined routes (UDRs) are custom routes that override system routes, often used to direct traffic through a firewall or virtual appliance. BGP routes are routes learned dynamically from on-premises networks via Border Gateway Protocol. Option A correctly describes system routes. Option B incorrectly assigns the description of BGP routes to UDRs. Option C incorrectly assigns the description of UDRs to BGP routes. Option D is false because system routes are not dynamically exchanged; they are automatically created by the system.

Answer

UDRs: Routes that are dynamically exchanged with on-premises networks.

Answer

BGP routes: Routes that override system routes when manually configured.

Answer

System routes: Routes that are dynamically exchanged with on-premises networks.

Question 5

Match each wireless concept to its description.

Accepted Answer

BSS: A single AP and its associated clients, forming the basic building block of a WLAN.. The question asks to match wireless concepts to their descriptions. Option A correctly describes a BSS as a single AP with associated clients. Option B describes an ESS (Extended Service Set), not BSS. Option C describes an IBSS (Independent BSS), also known as ad-hoc mode. Option D describes a BSSID, which is the MAC address of the AP's radio. Therefore, only option A is correct for BSS.

Answer

BSS: A wireless network with multiple APs connected by a distribution system, providing extended coverage.

Answer

BSS: A peer-to-peer wireless network without an AP, where stations communicate directly.

Answer

BSS: The MAC address of the access point, used to uniquely identify the BSS.

Question 6

Match each route type to its description.

Accepted Answer

Default route: A route used when no other specific route matches the destination.. Connected routes are automatically generated when a router interface is configured and active because the network is directly attached. Static routes are manually configured by an administrator to define specific paths. Dynamic routes are learned through routing protocols like OSPF or EIGRP. Default routes serve as a catch-all entry, used when no more specific route matches the destination.

Question 7

Match each OSPF adjacency requirement or concept to its most accurate description.

Accepted Answer

Neighbor discovery uses Hello packets to establish and maintain adjacencies.. OSPF neighbor discovery relies on Hello packets to establish and maintain adjacencies. Hello packets are multicast to discover neighbors, verify parameter compatibility, and serve as keepalives. Option A correctly describes this function, while the other options describe separate OSPF concepts. Option B describes the DR/BDR election, option C describes LSA flooding, and option D describes the SPF algorithm.

Answer

DR/BDR election reduces the number of LSAs flooded in a broadcast multiaccess network.

Answer

LSA flooding is the process by which OSPF routers exchange link-state information to build a common topology database.

Answer

The SPF algorithm is used to compute the shortest path to each destination based on the link-state database.

Question 8

Which two statements accurately describe default routes in a routed network?

Accepted Answer

A default route is used when no more specific route matches.. A default route is a fallback path used when no more specific route matches, which justifies option A. It is commonly represented as 0.0.0.0/0 in IPv4, so option B is also correct. Option C is incorrect because default routes are not always preferred over connected routes; connected routes are more specific (e.g., /24) and thus take precedence. Option D is false because default routes can be statically configured or dynamically learned via routing protocols such as OSPF or EIGRP. Option E is incorrect because default routes do not eliminate the need for route selection logic; routers still perform longest prefix match, and default routes are only used when no more specific match exists.

Answer

A default route is always preferred over connected routes.

Answer

A default route can exist only when dynamic routing is disabled.

Answer

A default route removes the need for route selection logic.

Question 9

Which statement most accurately describes administrative distance?

Accepted Answer

Administrative distance: A measure of the trustworthiness of a routing information source, used to select the best path when multiple routing protocols provide route information.. Administrative distance is correctly defined in option A as a measure of the trustworthiness of a routing information source. Options B, C, and D describe routing protocol metric, hop count, and route timer respectively, not administrative distance.

Answer

Administrative distance: The metric used by a routing protocol to determine the best path within that protocol, such as hop count or bandwidth.

Answer

Administrative distance: The number of routers a packet must traverse to reach its destination, used to compare routes from the same routing protocol.

Answer

Administrative distance: The time it takes for a route to be considered invalid if no updates are received, used to age out stale routes.

Question 10

Match each IPv4 route type to its most accurate source or description.

Accepted Answer

Directly connected route: route to a network attached to one of the router's interfaces. A directly connected route is automatically generated when an interface is configured and in up/up state. A default route is defined by its 0.0.0.0/0 network and mask and acts as the gateway of last resort. A floating static route is a static route with a higher administrative distance used as a backup. A static route is manually configured, not learned via OSPF or EIGRP, making option B incorrect.

Answer

Static route: route learned via a routing protocol such as OSPF or EIGRP

Question 11

Match each route-selection concept to its most accurate meaning.

Accepted Answer

Administrative distance: A measure of the trustworthiness of a routing protocol.. Administrative distance (AD) is a numeric value assigned to a routing protocol or static route that indicates its trustworthiness; a lower AD is preferred. Metric is a protocol-specific cost used by a routing protocol to compare multiple routes from the same source; the route with the lowest metric is chosen. Prefix length refers to the number of bits in the subnet mask that identifies the network portion of an IP address; longer prefixes are more specific. Longest prefix match is the algorithm routers use to select the most specific route (the route with the longest prefix length) for a destination IP address.

Question 12

Match each route source or concept to its most accurate description.

Accepted Answer

Directly connected route: A route that is automatically added to the routing table when an interface is configured with an IP address and is up/up.. A, C, and D correctly match each route source to its accurate description: directly connected routes are automatic, default routes are catch-all, and floating static routes are backup routes with higher AD. B is incorrect because static routes are manually configured, not learned via dynamic routing protocols.

Answer

Static route: A route that is learned via a dynamic routing protocol such as OSPF or EIGRP.

Question 13

Match each routing concept to its most accurate description.

Accepted Answer

Static routing: A network path manually configured by a network administrator.. Each routing concept matches its description as follows:
- Static routing: Manually configured by an administrator, offering precise control but no automatic adaptation to topology changes.
- Dynamic routing: Uses routing protocols (e.g., OSPF, EIGRP) to automatically discover and maintain routes based on the current network topology.
- Default route: A special route (0.0.0.0/0 in IPv4) that matches any destination not found in the routing table, acting as a gateway of last resort.
- Policy-based routing: Allows forwarding decisions based on attributes like source IP, packet size, or protocol, rather than solely on destination IP.

Question 14

Match each routing term to its most accurate meaning.

Accepted Answer

Route: A path that network traffic takes from source to destination. This question tests your understanding of basic routing terminology. A route is a path from source to destination. The next hop is the immediate next router or device to which packets are forwarded. A routing table contains rules that determine packet direction. A static route is manually configured and does not change automatically. Each of these definitions corresponds exactly to the terms listed.

Question 15

Match each IPv6 host-configuration concept to its most accurate description.

Accepted Answer

Stateless address autoconfiguration: Host generates its own IPv6 address using router advertisements. Each concept is correctly matched to its description: Stateless address autoconfiguration (SLAAC) allows hosts to generate their own IPv6 address using router advertisements. Stateful DHCPv6 involves a DHCP server assigning IPv6 addresses and other parameters. SLAAC (specifically) uses the prefix from router advertisements and EUI-64 to create the full address. DHCPv6-PD is used for prefix delegation, allowing a router to request a prefix from a DHCPv6 server to assign subnets.