Cisco Routing Protocols: RIP, EIGRP, and IP Addressing Fundamentals

Posted on Sep 3, 2025 in Telecommunication Technologies Engineering

Routing Information Protocol (RIP) Essentials

RIPv1 Characteristics and Limitations

Which of the following is considered a limitation of RIPv1?

RIPv1 does not send subnet mask information in its updates.

What are three characteristics of the RIPv1 routing protocol?

Uses hop count as a metric.
Considers a metric of 16 as infinity.
Calculates metrics using the Bellman-Ford algorithm.

What is the default update period in seconds for the RIP routing protocol?

30 seconds.

What are two true statements regarding the characteristics of RIPv1?

The data portion of a RIP message is encapsulated in a UDP segment.

RIPv2 Enhancements and Configuration

What is the maximum network diameter permitted by the default metric of RIPv2?

15 hops.

What are two reasons to implement RIP version 2 rather than RIP version 1?

RIP version 2 supports VLSM.
RIP version 2 supports authentication of routing updates.

How do RIPv1 and RIPv2 resemble each other? (Choose three.)

Both use hop count as a metric.
Both have the same metric value for infinite distance.
They both use split horizon to prevent routing loops.

What command or set of commands stops the RIP routing process?

RouterB(config)# no router rip

What happens if you enter an interface IP address for the network command in a RIPv1 configuration instead of a network address?

All interfaces in the same class as the configured network address are included in the RIPv1 routing process.

RIPv2 is the routing protocol configured on the routers in a network. If you enter the command Router(config-router)# no version 2 on the routers, what effect does this have on routing updates?

The router will receive updates from both version 1 and 2, but will only send updates for version 1.

What command will display RIP activity as it occurs in a router?

debug ip rip

Enhanced Interior Gateway Routing Protocol (EIGRP) Deep Dive

EIGRP Fundamentals and Features

Which of the following types of routes are indicated by EX entries in the EIGRP routing table? (Choose two.)

Routes learned from other routing protocols.
EIGRP routes that originate in different autonomous systems.

What two statements describe characteristics of EIGRP?

EIGRP is a distance vector routing protocol.
EIGRP supports classless routing and VLSM.

Which of the following best describes bounded updates used by EIGRP?

Partial updates are sent only to routers that need the information.

In the command router eigrp 20, what is the purpose of the number 20?

It identifies the autonomous system number for this EIGRP process.

By default, which two metrics are used by EIGRP to determine the best path between networks?

Delay
Bandwidth

What administrative distance is assigned by a router to a default route in EIGRP that is learned from a source outside the autonomous system?

170.

DUAL Algorithm and EIGRP Tables

What two actions will the EIGRP DUAL FSM perform if a link to a network disconnects?

Query neighbors for a route.
Search the topology table for a feasible successor.

Which of the following tables does the EIGRP DUAL algorithm use to keep the primary route to a destination?

The routing table (the topology table holds all learned routes, including feasible successors, but the primary route is installed in the routing table).

The output of show ip eigrp topology on a router displays a successor route and a feasible successor route to network 192.168.1.0/24. To reduce processor usage, what does EIGRP do when the primary route to this network fails?

The backup route to network 192.168.1.0/24 is installed in the routing table.

In a router running EIGRP, what database would maintain a list of feasible successors?

The topology table.

What information is stored in the EIGRP topology database for a destination path? (Choose three.)

The routing protocol.
The feasible distance of the path.
The cost of the route as published by the neighboring router.

IP Addressing and Routing Concepts

VLSM, CIDR, and Supernetting

Which of the following is found in the routing updates of classless routing protocols? (Choose two.)

32-bit address
Subnet mask

What does VLSM help to alleviate?

The IP address shortage.

What are the three interior routing protocols that support VLSM? (Choose three.)

OSPF
RIPv2
EIGRP

What does VLSM allow a network administrator to do?

Use multiple subnet masks in the same IP address space.

What is a supernet?

A summary of multiple classful network addresses.

What field did RFC 1723 add to the RIP message header to support VLSM and CIDR?

The subnet mask.

Classful vs. Classless Routing

What determines whether the router implements a classless path search process?: The command ip classless is enabled on the router.
What occurs when no ip classless is implemented on the router?: The router will only forward packets if a classful network match is found, even if a less specific (supernet) route exists for the destination.

Routing Table Analysis and Selection

The following line appears in the output of show ip route: R 192.168.3.0/24 [120 / 3] via 192.168.2.2, 00:00:30, Serial0/0. What is the value of the routing metric?

What are the two functions of the network command used when configuring routing protocols?

Identifies which networks will be included in routing updates.
Determines which interfaces can send and receive routing updates.

What term defines a collection of networks under the administrative control of a single entity that presents a common routing policy to the Internet?

Autonomous system.

Consider the following entry in the routing table: 192.168.8.0/24 [120 / 2] via 192.168.4.1, 00:00:26, Serial0/0/1. What type of route is this?

A Level 1 final network route.

A network is converged and the routing tables are complete. When forwarding a packet, what is the first criterion used to determine the best route in the routing table?

The path with the longest address and mask to match the destination.

A route to a destination network is learned from multiple routing protocols. What does a Cisco router use to select the preferred route to the destination installed in the routing table?

Administrative distance.

Private IP Addressing and Subnetting

A network administrator is asked to ensure the company’s IP address infrastructure complies with RFC 1918. What three IP address ranges from RFC 1918 could the network administrator use?

10.0.0.0/8
172.16.0.0/12
192.168.0.0/16

A network administrator has the task to split a Class C network among the departments of Quality Control, Sales, and Administration. Quality Control has 10 people, Sales has 28 people, and Administration has 6. What are the subnet masks to properly address the Quality Control and Sales departments? (Choose two.)

255.255.255.224 for Sales
255.255.255.240 for Quality Control

A router has a summary route to network 192.168.32.0/20 installed in its routing table. What range of networks does this route summarize?

192.168.32.0 – 192.168.47.255.

A network administrator installed four new routers running RIPv2. Router1 is a boundary router in the RIPv2 network and has a default route configured. Once the network has converged, the network administrator enters Router1(config-router)# default-information originate on Router1. How will this action affect the network?

It will propagate the default route to all routers in the network.