220-1101 Exam Dumps - CompTIA A+ Certification Exam: Core 1

The digitizer is a crucial component of a touchscreen device, responsible for translating touch actions into digital signals that the device can interpret. If a hard reset does not resolve the touchscreen's unresponsiveness, it's likely that the digitizer is damaged. Physical damage, such as cracks or heavy impacts, can impair the digitizer's ability to function correctly, leading to an unresponsive touchscreen. This type of hardware issue requires professional repair or replacement of the touchscreen assembly to restore functionality.References: Mobile Devices 1101.docx, "Touchscreen Technology" section.

A PSU (power supply unit) is a component that converts the AC power from the wall outlet into DC power that the PC components can use. A faulty or failing PSU can cause random system crashes, as well as other problems such as noise, overheating, or no power at all. A PSU can fail due to various reasons, such as age, dust, power surges, or poor quality.

To troubleshoot a PSU, the technician can use a multimeter to measure the voltage output of the PSU connectors. The voltage should be within the acceptable range of the specifications. For example, the 12V rail should be between 11.4V and 12.6V. If the voltage is too low or too high, the PSU is likely defective and needs to be replaced.

Alternatively, the technician can try swapping the PSU with a known good one and see if the system crashes persist. If the system works fine with a different PSU, then the original PSU is the problem and should be replaced.

The other options are not likely to fix the random system crashes. Testing the fan speed may help to diagnose overheating issues, but it is not related to the PSU. Disabling the USB ports may help to eliminate potential conflicts with USB devices, but it is not related to the PSU. Decreasing the RAM timings may help to improve performance and stability, but it is not related to the PSU.

References:

Fix Random PC Crashes: 10 Steps to Identify and Fix Issues

Why Does Windows Crash? The 9 Most Common Reasons

The correct answer is B. 22.

Port 22 is the default port for SSH (Secure Shell), a protocol that allows secure and encrypted remote login and command execution over a network. SSH uses public key cryptography to authenticate the client and the server, and to encrypt the data exchanged between them. SSH can be accessed through different ports, depending on the configuration of the server and the client. The default port for SSH is 22, but it can be changed to any other port for security reasons1.

Port 20 is the default port for FTP (File Transfer Protocol) data transfer, a protocol that allows file transfer between a client and a server over a network. FTP uses two ports: one for data transfer (port 20) and one for control commands (port 21). FTP does not provide encryption or authentication, and it is vulnerable to various attacks, such as packet sniffing, spoofing, or brute force. To secure FTP connections, protocols such as FTPS (FTP over SSL) or SFTP (SSH File Transfer Protocol) can be used2.

Port 23 is the default port for Telnet, a protocol that allows remote login and command execution over a network. Telnet does not provide encryption or authentication, and it sends data in plain text, which can be easily intercepted or modified by attackers. Telnet is considered obsolete and insecure, and it should be replaced by SSH or other secure protocols3.

Port 25 is the default port for SMTP (Simple Mail Transfer Protocol), a protocol that allows sending and receiving email messages over a network. SMTP does not provide encryption or authentication, and it can be exploited by spammers or hackers to send malicious or unwanted emails. To secure SMTP connections, protocols such as SMTPS (SMTP over SSL) or STARTTLS (Transport Layer Security) can be used.

Therefore, port 22 is the only port that allows for secure communications by default, as it uses SSH protocol. For more information about ports and their security, you can refer to the following web search results: How to secure your TCP/IP ports, What is an SSL port? A technical guide for HTTPS, HTTPS Port: What It Is, How to Use It, and More (2023).

A DNS record is a data entry in a DNS server that maps a domain name to a specific value, such as an IP address, a mail server, a name server, or a text string. There are different types of DNS records for different purposes, and each type has a specific format and syntax12.

The A record, also known as the address record, is the most common type of DNS record, and it is used to look up the IP address assigned to a domain name. The A record maps a domain name to an IPv4 address, which is a 32-bit numerical value that identifies a device on the internet. For example, the A record for www.google.com is 172.217.14.206 12.

The other options are not correct because they are not used to look up the IP address assigned to a domain name. The MX record, also known as the mail exchange record, is used to specify the mail servers that handle the email for a domain name. The MX record maps a domain name to a priority value and a host name of a mail server. For example, the MX record for gmail.com is 10 alt1.gmail-smtp-in.l.google.com12.

The NS record, also known as the name server record, is used to delegate a domain name to a set of authoritative name servers. The NS record maps a domain name to a host name of a name server that can provide authoritative answers for the domain name and its subdomains. For example, the NS record for example.com is ns1.example.com12.

The SPF record, also known as the sender policy framework record, is used to prevent email spoofing and spamming by validating the sender’s identity. The SPF record maps a domain name to a text string that specifies the authorized mail servers and IP addresses that can send email on behalf of the domain name. For example, the SPF record for microsoft.com is v=spf1 include:spf.protection.outlook.com -all12.

References:

DNS Configuration – CompTIA A+ 220-1101 – 2.6

CompTIA A+ Certification Core 1 (220-1101) [Video] - Packt Subscription, Section 2: Networking, Video 2.6: DNS Configuration

CompTIA A+ Certification Core 1 (220-1101) - GitHub, Slide Handout PDFs 1101, Chapter 2: Networking, Slide 2.6: DNS Configuration

To enable the printer to be shared across the network, the technician should configure the IP settings of the printer. The IP settings include the IP address, subnet mask, default gateway, and DNS server of the printer. The IP settings allow the printer to communicate with other devices on the network and access network resources such as print servers or cloud services.

The technician can configure the IP settings of the printer in different ways, such as:

Using the printer’s control panel or web interface to manually enter the IP settings or obtain them automatically from a DHCP server.

Using the printer’s software or driver to assign a static or dynamic IP address to the printer.

Using a network discovery tool to find and configure the printer on the network.

The technician should also make sure that the IP settings of the printer are compatible with the network configuration and do not cause any conflicts or errors.

DHCP (Dynamic Host Configuration Protocol) is a protocol that allows a device to automatically obtain an IP address and other network settings from a DHCP server, such as a home router. This simplifies the network configuration and avoids IP address conflicts. DHCP is a common requirement for home networks that have multiple devices that need Internet access.

A gateway is a device that connects two different networks, such as a home network and the Internet. A gateway usually performs routing functions, which means it determines the best path for packets to reach their destination. A gateway also often performs NAT (Network Address Translation), which allows multiple devices on a home network to share a single public IP address. A gateway is a necessary requirement for home networks that need Internet access.

References

Understanding DHCP on Home Networks

Basic home gateway services: DHCP, DNS, NAT

IP Addresses on Home Networks – A Beginner’s Guide

A scope is a term used to define a range of IP addresses available to assign using DHCP. DHCP stands for Dynamic Host Configuration Protocol, and it is a protocol that automatically assigns IP addresses and other network configuration parameters to devices on a network. A scope defines the start and end IP addresses, as well as other options, such as subnet mask, default gateway, and DNS servers.

SAS stands for Serial Attached SCSI, which is a bit serial interface successor to SCSI sponsored by ANSI and introduced in 20041. SAS is the most common interface for enterprise HDDs, especially those with high performance and high reliability requirements, such as 15,000rpm drives23. SAS offers faster data transfer speeds, lower power consumption, and better scalability than other interfaces1.