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

The correct answer is C. SPF.

SPF stands for Sender Policy Framework, which is a protocol that allows domain owners to specify which IP addresses are authorized to send email on behalf of their domains1. SPF helps prevent email spoofing and phishing by verifying the sender’s identity and preventing unauthorized use of their domain name12.

When an email is received, the receiving server checks the SPF record of the sender’s domain, which is a DNS TXT record that lists the valid IP addresses for that domain12. The server then compares the sender’s IP address with the SPF record and determines if it matches or not. If it matches, the email passes the SPF check and is accepted; if it does not match, the email fails the SPF check and is rejected or marked as spam12.

DKIM stands for DomainKeys Identified Mail, which is a protocol that allows domain owners to digitally sign their emails using a public-private key pair3. DKIM helps ensure the integrity and authenticity of email messages by verifying that they have not been tampered with or forged during transit3 .

MX stands for Mail Exchange, which is a type of DNS record that specifies the mail servers that are responsible for receiving email for a domain. MX records help direct incoming email to the correct destination and prioritize them based on preference values .

DMARC stands for Domain-based Message Authentication, Reporting and Conformance, which is a protocol that builds on SPF and DKIM and allows domain owners to define how receivers should handle unauthenticated or suspicious emails from their domains. DMARC helps protect domains from email fraud and abuse by providing feedback and reports on email delivery and authentication status .

Therefore, SPF is the only service among the options that checks whether the sender’s IP address is associated with the sender’s domain name when receiving email.

M.2 SSD and NVMe interface are the best options for storage devices and interfaces that provide the best performance. M.2 SSD is a form factor that allows for faster data transfer and lower power consumption than traditional SATA SSDs. NVMe is a protocol that enables direct communication between the SSD and the PCIe bus, bypassing the SATA controller and reducing latency and overhead. Together, they offer the highest speed and efficiency for storage devices.

A captive portal is a web page that requires users to agree to terms and conditions, enter credentials, or provide payment information before accessing a wireless network. Some devices, such as streaming media devices, may not have a web browser or a user interface to interact with the captive portal. One possible solution is to connect to the hotspot on the user’s device, such as a smartphone or a tablet, and use it as a bridge to access the internet through the wireless network. The user’s device can authenticate with the captive portal and share its internet connection with other devices via Wi-Fi, Bluetooth, or USB. Reference: https://partners.comptia.org/docs/default-source/resources/a-core-1-content-guide (page 12)

Shared resources is the concept that allows several websites from different companies to be housed on the same virtual server. A virtual server is a software-based server that runs on a physical server and can host multiple virtual machines (VMs). Each VM can run a different operating system and application, such as a website, and have its own allocated resources, such as CPU, memory, disk space, and network bandwidth. However, the VMs share the underlying hardware resources of the physical server, which reduces the cost and complexity of maintaining separate servers for each website. This also enables rapid scalability, as new VMs can be created or deleted as needed.

One of the methods to host multiple websites on the same virtual server is to use virtual hosts. Virtual hosts are a feature of web servers, such as Apache, that allow the web server to serve different websites based on the domain name or IP address requested by the client. For example, a web server can host two websites, a.example.com and b.example.com, on the same virtual server and the same port (such as 80 or 443), by using virtual hosts to map each domain name to a different document root directory. The web server will then deliver the content of the corresponding website to the client based on the domain name in the HTTP request header.

Optical media, such as CDs, DVDs, or Blu-ray discs, are a suitable choice for backing up a large collection of DVDs and photos in the most economical way. Optical media are inexpensive, widely available, and have a long shelf life. They can store large amounts of data, up to 50GB on a dual-layer Blu-ray disc, and can be easily labeled and organized. Optical media are also less prone to mechanical failure, data corruption, or accidental deletion than hard disk drives (HDDs) or solid state drives (SSDs).

The other options are not as economical or suitable for this purpose. A 5,400rpm HDD is a slow and noisy type of HDD that has moving parts that can wear out or break. A HDD also consumes more power and generates more heat than an SSD. A M.2 NVMe SSD is a fast and compact type of SSD that uses a PCIe interface to transfer data. However, an SSD is more expensive than an HDD or optical media, and has a limited number of write cycles before it degrades. A SAS RAID array is a complex and costly system that uses multiple HDDs or SSDs connected by a Serial Attached SCSI (SAS) interface to provide redundancy, performance, or both. A RAID array requires a RAID controller, a compatible motherboard, and a dedicated power supply.

The correct answer is A. Imaging drum.

An imaging drum is a part of a laser printer that transfers the toner to the paper. The imaging drum is coated with a photosensitive material that reacts to light and creates an electrostatic charge. The charge attracts the toner particles from the cartridge and forms an image on the drum. The image is then transferred to the paper by heat and pressure from the fuser assembly.

If the imaging drum is defective or damaged, it can cause various printing problems, such as solid black pages, blank pages, streaks, spots, or faded prints. A solid black page can occur when the imaging drum is unable to create a charge pattern on its surface, and instead attracts all the toner from the cartridge. This can happen due to a faulty laser unit, a dirty or scratched drum surface, or a worn-out drum.

To fix this issue, the technician should replace the imaging drum with a new one. The imaging drum usually has a limited lifespan and needs to be replaced periodically. The technician should also check the toner cartridge and the fuser assembly for any signs of damage or leakage123

A cable tester and a crimper are the best tools to execute the task of replacing all RJ45 cables in a customer environment. A cable tester can be used to check the continuity and quality of a cable, and a crimper can be used to attach RJ45 connectors to the ends of a cable. An optical fiber tester is a tool that can be used to test fiber optic cables, which are not RJ45 cables. Scissors are not a tool for replacing cables, but for cutting them. A coaxial cable is a type of cable that has a single copper conductor at its center, which is not an RJ45 cable either. A screwdriver is not a tool for replacing cables, but for fastening or loosening screws.

A load balancer is a device or software that distributes network traffic across multiple servers or resources, such as web server farms, to optimize performance, reliability, and scalability. A load balancer controls the flow of users connecting to web server farms and prevents overutilization on any individual server by using various algorithms, such as round robin, least connections, or weighted distribution. A load balancer can also provide health checks, failover, caching, compression, encryption, and other features to enhance the user experience and security.