CompTIA CompTIA Certifications FC0-U51 Questions & Answers

• Question 41:

  Which of the following is the lightest but most expensive battery used in laptops?

  A. NiMH

  B. NiCad

  C. Li-Ion

  D. Sodium-Ion

  Correct Answer: C

  Li-Ion or Lithium Ion battery is the lightest but most expensive battery used in laptops. Li- Ion battery has a longer life as compared to NiCad and NiMH batteries. Answer option B is incorrect. Nickel-Cadmium (NiCad) batteries are no longer used in laptops. NiCad batteries are heavy and have shorter life as compared to NiMH batteries. Answer option D is incorrect. There is no battery such as Sodium-Ion. Answer option A is incorrect. A Nickel-Metal Hydride (NiMH) battery has 30 percent more life than a NiCad battery. NiMH is more expensive and takes more time to recharge as compared to NiCad. Some laptops still use NiMH batteries.

• Question 42:

  Which of the following protocols is widely used for setting up and tearing down multimedia communication sessions such as voice and video calls over the Internet (VoIP)?

  A. LDAP

  B. ICMP

  C. UDP

  D. SIP

  Correct Answer: D

  Session Initiation Protocol (SIP), designed by Henning Schulzrinne and Mark Handley in 1996, is a signaling protocol, widely used for setting up and tearing down multimedia communication sessions such as voice and video calls over the Internet (VoIP). Other feasible application examples include video conferencing, streaming multimedia distribution, instant messaging, presence information and online games. The protocol can be used for creating, modifying, and terminating two-party (unicast) or multiparty (multicast) sessions consisting of one or several media streams. The modification can involve changing addresses or ports, inviting more participants, adding or deleting media streams, etc. The SIP protocol is a TCP/IP-based Application Layer protocol. Within the OSI model, it is sometimes placed in the session layer. SIP is designed to be independent of the underlying transport layer; it can run on TCP, UDP, or SCTP. It is a text-based protocol, sharing many elements of the Hypertext Transfer Protocol (HTTP), upon which it is based, allowing for easy inspection by administrators. SIP clients typically use TCP or UDP (typically on port 5060 and/or 5061) to connect to SIP servers and other SIP endpoints. Answer option A is incorrect. Lightweight Directory Access Protocol (LDAP) is a protocol used to query and modify information stored within directory services. Answer option B is incorrect. Internet Control Message Protocol (ICMP) is an integral part of IP. It is used to report an error in datagram processing. The Internet Protocol (IP) is used for host-to-host datagram service in a network. The network is configured with connecting devices called gateways. When an error occurs in datagram processing, gateways or destination hosts report the error to the source hosts through the ICMP protocol. The ICMP messages are sent in various situations, such as when a datagram cannot reach its destination, when the gateway cannot direct the host to send traffic on a shorter route, when the gateway does not have the buffering capacity, etc. Answer option C is incorrect. User Datagram Protocol (UDP) is often used for one-to-many communications, using broadcast or multicast IP datagrams. Microsoft networking uses UDP for logon, browsing, and name resolution. UDP is a connectionless and unreliable communication protocol. It does not guarantee delivery, or verify sequencing for any datagram. UDP provides faster transportation of data between TCP/IP hosts than TCP. Reference: "http://en.wikipedia.org/ wiki/Session_Initiation_Protocol"

• Question 43:

  Which of the following cache levels are implemented on microprocessors?

  Each correct answer represents a complete solution. Choose two.

  A. Level 0 (L0) cache

  B. Level 1 (L1) cache

  C. Level 5 (L5) cache

  D. Level 2 (L2) cache

  Correct Answer: BD

  The Level 1 (L1) cache is implemented on microprocessors. The L1 cache is a type of memory implemented inside the microprocessor chip. It is the fastest memory in the computer. It contains the current working set of data and code. Cache

  memory is used to store frequently used information, so that the processor can access this information without delay.

  Level 2 (L2) cache is employed between main memory and L1 cache. The L2 cache contains additional data and code. In old architecture, L2 cache is mounted on the motherboard, which means that it runs at the motherboard's speed. In

  modern architecture, L2 caches are built directly into the microprocessor. Answer options C and A are incorrect. There are no such cache levels as level 0 and level 5.

  Reference: Contents: "http://en.wikipedia.org/wiki/CPU_cache"

• Question 44:

  Which of the following technologies can be used to encrypt the wireless networks?

  Each correct answer represents a complete solution. Choose two.

  A. WAP

  B. Kerberos

  C. WEP

  D. WPA

  Correct Answer: CD

  WPA and WEP can be used to encrypt wireless networks. WPA stands for Wi-Fi Protected Access. It is a wireless security standard. It provides better security than WEP (Wired Equivalent Protection). Windows Vista supports both WPA-PSK and WPA-EAP. Each of these is described as follows: WPA-PSK: PSK stands for Preshared key. This standard is meant for home environment. WPA-PSK requires a user to enter an 8-character to 63-character passphrase into a wireless client. The WPA converts the passphrase into a 256-bit key. WPA-EAP: EAP stands for Extensible Authentication Protocol. This standard relies on a back-end server that runs Remote Authentication Dial-In User Service for user authentication. Note: Windows Vista supports a user to use a smart card to connect to a WPA-EAP protected network. Wired Equivalent Privacy (WEP) is a security protocol for wireless local area networks (WLANs). It has two components, authentication and encryption. It provides security, which is equivalent to wired networks, for wireless networks. WEP encrypts data on a wireless network by using a fixed secret key. WEP incorporates a checksum in each frame to provide protection against the attacks that attempt to reveal the key stream. Answer option B is incorrect. Kerberos is a computer network authentication protocol that allows individuals communicating over a non-secure network to prove their identity to one another in a secure manner. Answer option A is incorrect. The Wireless Access Protocol (WAP) is a technology used with wireless devices. The functionality of WAP is equivalent to that of TCP/IP. WAP uses a smaller version of HTML called Wireless Markup Language (WML) to display Internet sites. Reference: "http://en.wikipedia.org/wiki/Wi-Fi_Protected_Access",

  "http://en.wikipedia.org/wiki/Wired_Equivalent_Privacy"

• Question 45:

  Which of the following file attributes are not available on a FAT32 partition?

  Each correct answer represents a complete solution. Choose two.

  A. Compression

  B. Archive

  C. Hidden

  D. Encryption

  E. Read Only

  Correct Answer: AD

  File attributes such as Compression and Encryption are not available on FAT32 partitions. The following file attributes are available on FAT32 partitions: Hidden Read Only Archive System

  The FAT32 file system is an enhancement of the FAT16 file system. FAT32 can support hard disk drives larger than 2GB (maximum 2TB) without having to use multiple partitions. It is more efficient as compared to 16-bit FAT on larger disks,

  as FAT32 decreases the cluster size on large hard disk drives, thereby reducing the amount of unused space.

  The Compression and Encryption file attributes are available on NTFS partitions.

  What is NTFS? Hide

  NTFS is a high-performance file system proprietary to Microsoft. NTFS supports file-level security, compression, and auditing.

  It also supports large volumes and powerful storage solution such as RAID. The latest feature of NTFS is its ability to encrypt files and folders to protect sensitive data. Reference: "http://www.webopedia.com/TERM/F/FAT32.htm"

• Question 46:

  You work as a computer technician. When you start your computer, you find that the computer's CMOS battery has failed. You replace the CMOS battery.

  What will be your next step after replacing the CMOS battery?

  A. Run the DEFRAG utility.

  B. Create a partition on the hard disk drive.

  C. Run the SCANDISK utility.

  D. Reboot the computer and set the date and time.

  Correct Answer: D

  When a computer's CMOS battery is replaced, the system clock of the computer is reset. Therefore, your next step after replacing the CMOS battery will be to reboot the computer and to set the date and time.

  What is a CMOS battery? Hide

  A Complementary Metal Oxide Semiconductor (CMOS) battery is installed on the motherboard. It provides backup to CMOS to store computer hardware configuration, date, and time settings when a computer's main power is off. Note:

  Incorrect date and time on the computer indicate failure of the CMOS battery. Answer option C is incorrect. SCANDISK is a Windows utility that detects and corrects corruption in the disk when a computer is not shut down properly. It also

  checks and deletes the corrupt files that may be using up disk space. This helps in improving the performance of a computer.

  Answer option A is incorrect. DEFRAG is a system utility used to consolidate the fragmented files stored on the hard disk of a computer. The fragmented files are those files that are saved or stored in different locations of the hard disk. The

  tool arranges such files and stores them on the hard disk in contiguous blocks. The operating system can access these files at a faster rate than the fragmented ones. Answer option B is incorrect. Creating a partition on the hard disk drive

  has nothing to do with the issue.

  Reference: TechNet, Contents: "Chapter 21 - Troubleshooting Startup and Disk Problems"

• Question 47:

  Which of the following interfaces is the current standard for digital LCD monitors?

  A. DVE

  B. SVGA

  C. DVI

  D. VGA

  Correct Answer: C

  DVI interface is the current standard for digital LCD monitors. DVI stands for Digital Visual Interface. It is a standard for high speed, high resolution digital display invented by Digital Display Working Group (DDWG). DVI accommodates analog and digital interfaces with a single connector. New video cards have DVI as well as VGA ports built into them. Most of LCD monitors come with a 15-pin VGA connection cable, even if they are capable of handling digital signals coming from DVI connections. However, some monitors come with both types of cables. DVI has three main categories of connectors. They are: DVI-A, DVI-D, and DVI-I. DVI-A is an analog-only connector, DVI-D is a digital-only connector, and DVI-I is an analog/digital connector. DVI-D and DVI-I connectors are of two types: single link and dual link. DVI supports UXGA and HDTV with a single set of links. Higher resolutions such as 1920 x 1080, 2048 x 1536, or more can be supported with dual links. Answer options D and B are incorrect. VGA and SVGA are old standards for monitors. A VGA or SVGA interface is a 15-pin, three rows, female connector, on the back of a PC used for connecting monitors. Answer option A is incorrect. There is no such interface standard for digital LCD monitors as DVE. Reference: http://en.wikipedia.org/wiki/Digital_Visual_Interface

• Question 48:

  Which of the following is the bandwidth of an SCSI Ultra2 Wide I/O port?

  A. 50 MBps

  B. 160 MBps

  C. 320 MBps

  D. 80 MBps

  Correct Answer: D

  The SCSI Ultra2 Wide I/O port has a bandwidth of 80 MBps. Small Computer System Interface (SCSI) is the second most popular drive interface in use today after the Integrated Drive Electronics (IDE) interface. SCSI is faster than IDE and

  supports more devices.

  SCSI devices, such as hard disk drives and CD-ROM drives, are better suited to a network environment in which many users access shared drives simultaneously. SCSI has three standards: SCSI-1, SCSI-2, and SCSI-3.

  Answer option A is incorrect. The IEEE 1394a S400 I/O port has a bandwidth of 50 MBps. Answer option B is incorrect. The SCSI Ultra3 I/O port has a bandwidth of 160 MBps. Answer option C is incorrect. The SCSI Ultra4 port has a

  bandwidth of 320 MBps.

• Question 49:

  Which of the following devices has a 15-pin 3 row connector?

  A. Joystick port

  B. VGA monitor

  C. Parallel port

  D. Serial port

  Correct Answer: B

  The VGA monitor uses a 15-pin 3 row connector to connect to a video adapter. Older Color Graphic

  Array (CGA) video standard monitors use 9- pin connectors to connect to DB-9 female connectors on CGA adapters.

  Answer option D is incorrect. Serial port is the primary means for connecting modems and mouse to a computer. There are two types of serial port connectors, 9-pin and 25-pin. The word serial refers to the that data is sent in series, one bit at

  a time, over a single wire. This design is significantly slower than sending 8 bits at a time via a parallel channel, but serial signals can travel much farther without degradation. Answer option A is incorrect. The joystick port has a 15-pin 2 row

  male connector. Answer option C is incorrect. A parallel port is a 25-pin 2 row female connector on the back of a PC.

  It is used to connect printers, scanners, etc. A parallel port transfers information between computers and peripheral devices 8 bits at a time.

  ECP, EPP, and SPP are types of parallel ports.

• Question 50:

  What is the display resolution of the WUXGA standard?

  A. 1024 x 768 pixels

  B. 1280 x 1024 pixels

  C. 1920 x 1200 pixels

  D. 1600 x 1200 pixels

  Correct Answer: C

  WUXGA stands for Widescreen Ultra eXtended Graphics Array. It is a display standard that refers to video adapters. This display standard is capable of displaying a resolution of 1920 x 1200 pixels with a 16:10 screen aspect ratio. WUXGA resolution is currently available in high-end LCD televisions and computer monitors. Answer option A is incorrect. XGA stands for eXtended Graphics Array. It is a display standard that refers to video adapters. IBM introduced this display standard in 1990. It is capable of displaying the resolution of 1024 x 768 pixels. Answer option D is incorrect. UXGA stands for Ultra eXtended Graphics Array. It is a display standard that refers to video adapters. This display standard is capable of displaying the resolution of 1600 x 1200 pixels. A UXGA display provides four times more pixels than an 800 x 600 display. Answer option B is incorrect. SXGA stands for Super eXtended Graphics Array. It is a display standard that refers to video adapters. This standard is an enhancement of the standard XGA resolution developed by IBM. It is capable of displaying the resolution of 1280 x 1024 pixels. Reference: "http://en.wikipedia.org/wiki/WUXGA"