最新の[2025年02月20日] 実際に出る検証済みの100-490問題集 [Q24-Q46]

最新の[2025年02月20日] 実際に出る検証済みの100-490問題集

合格させるCisco 100-490試験更新されたのは74問があります

質問 # 24
ESD is the sudden and momentary electric current that flows between two objects at different electrical potentials, caused by direct contact or induced by an electrostatic field. Which three tools are used to avoid ESD? (Choose three.)

A. negative static bag
B. latex gloves
C. antistatic bag
D. ESD wrist strap
E. antistatic mat
F. negative static mat

正解：C、D、E

解説：
Electrostatic Discharge (ESD) poses a significant risk to delicate electronic components. Here's why the correct answers are essential tools for ESD protection:
Antistatic Mat: Provides a grounded surface to work on, dissipating static buildup from your body and the components you're handling.
ESD Wrist Strap: When connected to a grounding point (often on the antistatic mat), this strap creates an electrical path to safely discharge static electricity from your body.
Antistatic Bag: These special bags are designed to shield sensitive components from static charge, crucial for storing and transporting electronic parts.
Why other options are incorrect:
Negative static bag, negative static mat: These terms don't exist in standard ESD protection practices. The focus is on creating a grounded environment to neutralize static charges.
Latex gloves: While they offer insulation, they can actually generate static electricity, increasing the risk of ESD damage.

質問 # 25
What are two components of a WAN connection? (Choose two.)

A. switch
B. router
C. CSU/DSU
D. hub
E. bridge

正解：B、C

質問 # 26
Which Windows-based text editor is preferred for working with a simple text document, such as a Cisco configuration?

A. Microsoft Access
B. Microsoft Excel
C. Microsoft Word
D. Microsoft Notepad

正解：D

解説：
Microsoft Notepad is the preferred text editor for working with Cisco configuration files and other simple text documents for several reasons:
Plain Text Focus: Notepad is designed specifically for plain text editing. It does not add any formatting, hidden characters, or metadata that could interfere with the configuration file's structure.
Cisco Syntax Compatibility: Cisco configurations rely on specific syntax and spacing. Notepad preserves these elements accurately.
Universality: Notepad is a basic text editor included in all versions of Windows, ensuring accessibility and eliminating the need for additional software.
Why other options are not ideal:
Microsoft Word: Word is a word processor and includes formatting, fonts, and other features that are not compatible with Cisco configuration files. This formatting can corrupt the configuration.
Microsoft Access: Access is a database management system, not suited for text file editing.
Microsoft Excel: Excel is a spreadsheet application and adds its own structure and formatting that conflicts with configuration file formats.

質問 # 27
At the interface configuration prompt, which command returns you to the main configuration prompt?

A. quit
B. exit
C. clear
D. end

正解：B

質問 # 28
Which set of steps best describes how to assign a static IP address to the Ethernet port on a computer?

A. From the Network and Sharing Center, click Change adapter, then double-click a local area connection. Select Internet Protocol (TCP/IP) > Properties > Use the Following Address, and then configure the IP information.
B. From the Network and Sharing Center, double-click Local Area Connection. Select Properties > iPass Protocol (IEEE 802.1x) > Properties > Static IP.
C. From the Network and Sharing Center, click Internet Protocol (TCP/IP), and follow the New Connection Wizard instructions.
D. Click Start. Enter cmd and click OK. Enter the IP address XXX.XXX.XXX.XXX.

正解：A

解説：
To assign a static IP address to the Ethernet port on a computer, particularly in a Windows environment, you would navigate to the Network and Sharing Center. From there, you would access the adapter settings, select your local area connection, and then enter the properties for Internet Protocol Version 4 (TCP/IPv4). Within the properties, you would choose the option to use a specific IP address and enter the desired IP information, including the IP address, subnet mask, and default gateway. This process sets a static IP address for the Ethernet port, ensuring that the computer will always use the same IP address every time it connects to the network, which is useful for various network configurations and applications. Reference := How to Assign a Static IP Address in Windows 10 or Windows 11 - How-To Geek, How to Set Up a Static IP Address | PCMag

質問 # 29
Which two statements about Telnet and SSH are true? (Choose two.)

A. Telnet is preferred over SSH for security reasons.
B. SSH uses the well-known TCP port 23 for its communication.
C. SSH is a protocol that provides a secure remote access connection to network devices.
D. Telnet is a protocol that provides a secure remote access connection to network devices.
E. A Telnet network management connection is dropped when a router reboots.

正解：C、E

解説：
A . Correct. SSH, or Secure Shell, is indeed a protocol that provides a secure remote access connection to network devices. It encrypts the data to ensure secure transmission over insecure networks like the internet1.
C . Correct. Telnet connections are not secure and are terminated when a router reboots. This is because Telnet does not have any mechanism to maintain the connection in case of network interruptions or device reboots1.
B, D, and E are incorrect because: B. SSH uses TCP port 22 by default, not port 23, which is used by Telnet1. D . Telnet does not provide a secure connection; it transmits data in plain text, which can be intercepted easily1. E. SSH is preferred over Telnet for security reasons because it provides encrypted connections and authentication mechanisms, which Telnet does not1.
Reference :=
1: GeeksforGeeks - Difference between SSH and Telnet 2: phoenixNAP - Telnet vs. SSH: How Is SSH Different From Telnet? 3: Guru99 - Telnet vs SSH - Difference Between Them 4: Difference Between - Difference Between Telnet and SSH

質問 # 30
Which command sends an echo request packet to the target host and then waits for an echo response message?

A. connect
B. access
C. ping
D. echo

正解：C

解説：
Section: Cisco IOS Software Operation

質問 # 31
The pins on an RJ-45 cable plug are numbered from 1 through 8. When the metal pins of the plug are facing toward you, pin 1 is the leftmost pin. Which two sets of pins are looped on an RJ-45 56K loopback plug? (Choose two.)

A. pins 1 and 7
B. pins 2 and 5
C. pins 2 and 7
D. pins 1 and 4
E. pins 2 and 8

正解：A、E

解説：
Loopback plugs are used to test the physical connections and configurations of network equipment. In a 56K modem loopback plug, the following pins are looped to create a test signal:
Pins 1 and 7 (Transmit): Looping the transmit pins back to each other allows the device to test its own signal transmission.
Pins 2 and 8 (Receive): Looping the receive pins back to each other allows the device to test its ability to receive its own signal.
Understanding RJ-45 Wiring:
RJ-45 connectors are standardized and have a specific pinout for various applications like Ethernet networking and analog telephony connections. You can find resources online that show the standard RJ-45 color coding and pin assignments.

質問 # 32
Which router port is used for dial-in access to the router for CLI management purposes and does not usually pass normal network traffic?

A. Gigabit Ethernet
B. AUX
C. channelized serial
D. Fast Ethernet

正解：B

解説：

The AUX (Auxiliary) port on a router is used for dial-in access for CLI (Command Line Interface) management purposes. It is typically connected to a modem and allows an administrator to dial into the router's CLI for remote management. This port is not used for passing normal network traffic, which differentiates it from other ports like Fast Ethernet or Gigabit Ethernet that handle regular data flow. The AUX port is specifically designed as a backup async port for management access1.

質問 # 33
Which two Cisco Nexus 3400 Series switches support 400-Gbps Ethernet ports? (Choose two.)

A. Cisco Nexus 34200YC-SM
B. Cisco Nexus 3464C
C. Cisco Nexus 3432D-S
D. Cisco Nexus 3408-S
E. Cisco Nexus 34180YC

正解：C、D

解説：
Section: Cisco Equipment and Related Hardware
Explanation/Reference: https://www.cisco.com/c/en/us/td/docs/switches/datacenter/nexus3400s/sw/922/interfaces/ configuration/guide/b_Cisco_Nexus_3400_NX-OS_Interfaces_Configuration_Guide_922/ b_Cisco_Nexus_3400_NX-OS_Interfaces_Configuration_Guide_9z_chapter_010.html

質問 # 34
What does Cisco use for Return Materials Authorization tracking of field-replaceable parts?

A. FRU number
B. product number
C. RMA number
D. serial number

正解：C

解説：
Section: Service-related Knowledge

質問 # 35
Which command provides detailed information about the components that are installed on a router, such as the model, PID, and serial number?

A. show chassis
B. show inventory
C. show items
D. show router

正解：B

解説：
The show inventory command in Cisco IOS is designed specifically to display detailed hardware inventory information about a Cisco device. This includes:
Component Name: The name or type of each module or card installed.
PID (Product ID): The unique product identifier for the module.
VID (Version ID): The version identifier for the module.
Serial Number: The unique serial number assigned to the module.
Why other options are incorrect:
show chassis: Some Cisco devices support a show chassis command, but the information provided usually focuses on the physical chassis rather than detailed component inventory.
show items: This is not a standard Cisco IOS command.
show router: This command doesn't provide the level of granular hardware information that show inventory does.

質問 # 36
Which two statements about a SmartJack are true? (Choose two.)

A. It operates at Layer 2 of the OSI model.
B. It regenerates the signal to compensate for signal degradation from line transmission.
C. It acts as a concentration point for dial-in and dial-out connections.
D. It provides channel testing.
E. It provides signal conversion.

正解：B、E

解説：
Section: Cisco Equipment and Related Hardware
Explanation

質問 # 37
Which Windows-based text editor is preferred for working with a simple text document, such as a Cisco configuration?

A. Microsoft Access
B. Microsoft Excel
C. Microsoft Word
D. Microsoft Notepad

正解：D

質問 # 38
Which Xmodem option is used to enhance error checking of an image that is copied to flash memory?

A. -c
B. -e
C. -x
D. -r

正解：A

質問 # 39
What are two purposes of a USB thumb drive? (Choose two.)

A. to save the system log
B. to copy IOS images to and from a PC
C. to copy configuration files to and from a PC
D. to increase system memory size
E. to save router hardware information

正解：B、C

解説：
USB thumb drives (also called flash drives) serve several practical purposes in networking:
File Transfer: They are excellent for transferring Cisco router or switch configuration files between the device and a PC. This allows you to back up configurations, easily restore configurations, or work with them offline.
IOS Image Storage: USB thumb drives are convenient for storing and transferring Cisco IOS images, especially when you need to upgrade or recover network devices.
Why other options are incorrect:
to save the system log: While you might temporarily store log files on a USB drive, routers and switches generally utilize internal memory or a remote syslog server for logging purposes.
to save router hardware information: Hardware inventory information obtained from commands like show inventory is often copied and pasted to text files, which can then be stored on a USB drive. However, the drive itself doesn't directly save or store this hardware information.
to increase system memory: USB drives are not designed to act as additional system memory (RAM) for a router or switch.

質問 # 40
The pins on an RJ-45 cable plug are numbered from 1 through 8. When the metal pins of the plug are facing toward you, pin 1 is the leftmost pin. Which two sets of pins are looped on an RJ-45 56K loopback plug?
(Choose two.)

A. pins 1 and 7
B. pins 2 and 5
C. pins 2 and 8
D. pins 1 and 4
E. pins 2 and 7

正解：B、D

解説：
Section: Cisco Equipment and Related Hardware
Explanation/Reference:

質問 # 41
Which two commands identify the serial number of a Cisco router? (Choose two.)

A. show version
B. show archive
C. show inventory
D. show environment
E. show run

正解：A、C

解説：
The commands that can be used to identify the serial number of a Cisco router are show inventory and show version. The show inventory command provides detailed information about the hardware inventory, including the serial numbers of the device and its components1. The show version command displays the router's configuration, including the version of the operating system, the last reboot reason, and the hardware serial number, which is listed as the "Processor board ID" in the command output2. These commands are essential for network administrators to document and manage network equipment.

質問 # 42
Which two IPv4 addresses can be assigned to a host computer? (Choose two.)

A. 292.10.3.4
B. 10.1.1.20
C. 192.168.10.15
D. 0.0.0.0
E. 255.255.255.255

正解：B、C

解説：
IPv4 addresses consist of four octets, each ranging from 0 to 255. The addresses are used to uniquely identify devices on a network.
A . 255.255.255.255 is reserved for broadcast messages to all hosts on the local network, so it cannot be assigned to a single host.
B . 10.1.1.20 falls within the range of private IP addresses (10.0.0.0 to 10.255.255.255) and can be assigned to a host within a private network.
C . 0.0.0.0 is used to denote an unknown or non-applicable target address, often used as a default route, and cannot be assigned to a host.
D . 192.168.10.15 is also within the range of private IP addresses (192.168.0.0 to 192.168.255.255) and can be assigned to a host within a private network.
E . 292.10.3.4 is not a valid IPv4 address because the first octet exceeds the maximum value of 255.
Reference:
IPv4 Addressing
Valid IP Address
IP Address Validation

質問 # 43
How many pairs of copper wire does a UTP cable have?

A. 0
B. 1
C. 2
D. 3

正解：D

解説：
A standard UTP (Unshielded Twisted Pair) cable contains 4 pairs of copper wires, which are twisted together to help cancel out electromagnetic interference and support data transmission across various networking and telecommunications applications1. Each pair consists of two individual copper cables twisted around each othe

質問 # 44
What are the choices for modes of operation when deploying Cisco Catalyst 3850 Series switches?

A. Boot mode and Run mode
B. Exec mode and User mode
C. Install mode and Bundle mode
D. Active mode and Standby mode

正解：C

解説：
When deploying Cisco Catalyst 3850 Series switches, there are two modes of operation to choose from: Install mode and Bundle mode. Install mode is the default mode for the switch and uses a package-provisioning file named packages.conf to boot the switch. It allows for a more complete set of features and requires fewer resources upon boot1. Bundle mode, on the other hand, is similar to using traditional monolithic Cisco IOS images to boot the switch. It consumes more memory than Install mode because the packages are extracted from the bundle and copied to the RAM2. Cisco recommends using Install mode for operation due to its efficiency and feature set2.

質問 # 45
Which two commands set the configuration register value? (Choose two.)