The 'CAT' (Category) rating on a multimeter relates to its capability to

The 'CAT' (Category) rating on a multimeter relates to its capability to:

• Survive in tough environments
• Reduce user hazards
• Maintain high accuracy
• Provide extended battery life 

 

EXPLANATION

The Category rating, typically CAT I, II, III, IV etc, relates to the ability of the meter to avoid creating a safety hazard when subjected to a massive overload, as for example when inadvertently connected directly across a supply when on a current range. It does not necessarily imply that the meter will survive the abuse. Rather, that the result should not include user injury due to fire, insulation failure, arcing or bursting open of the case.

Budget meters sold for use on small electronic projects do not typically have the protection devices (Especially, high breaking-current fuses) fitted to meters intended for measurements on distribution boards, etc. Therefore anyone intending such work should choose a meter with a suitable CAT rating.

http://support.fluke.com/find-sales/download/asset/1263690_6116_eng_h_w.pdf

SOURCE

http://support.fluke.com/find-sales/download/asset/1263690_6116_eng_h_w.pdf

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What is the limiting factor that prevents older PCs from using a hard drive larger than 2.2 terabytes?

What is the limiting factor that prevents older PCs from using a hard drive larger than 2.2 terabytes?

• GPT (GUID Partition Table)
• MBR (Master Boot Record)
• RAM (Random Access Memory)
• UEFI (Unified EFI) 

 

EXPLANATION

This limit arises from the maximum size of the master boot record (MBR) partitioning method used by most personal computers. BIOS systems with MBR disks use 32-bit values to describe the starting offset and length of a partition. Due to this size limit, MBR allows a maximum disk size of approximately 2.2 TB and a maximum of four primary partitions.
UEFI supports the GUID Partition Table (GPT), a more flexible partitioning scheme. GPT disks use 64-bit values to describe partitions, allowing larger partitions. GPT also fixes other issues related to MBR (data integrity, backup tables, maximum number of partitions, ...). Using 64-bit values, GPT can handle disks of up to 9.4 x 10^21 bytes or 9.4 zettabytes (ZB).

SOURCE

http://www.uefi.org/sites/default/files/resources/UEFI_Drive_Partition_Limits_Fact_Sheet.pdf

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Which of the following protocols is not directly related to VOIP?

Which of the following protocols is not directly related to VOIP?

• Real-time Transport Protocol (RTP)
• Session Initiation Protocol (SIP)
• File Transfer Protocol (FTP)
• Inter-Asterisk eXchange (IAX) 

 

EXPLANATION

Voice over Internet Protocol (also voice over IP, VoIP or IP telephony) is a methodology and group of technologies for the delivery of voice communications and multimedia sessions over Internet Protocol (IP) networks, such as the Internet.
Voice over IP has been implemented in various ways using both proprietary protocols and protocols based on open standards. VoIP protocols include:

Session Initiation Protocol (SIP) H.323Media Gateway Control Protocol (MGCP) Gateway Control Protocol (Megaco, H.248) Real-time Transport Protocol (RTP) Real-time Transport Control Protocol (RTCP) Secure Real-time Transport Protocol (SRTP) Session Description Protocol (SDP) Inter-Asterisk eXchange (IAX) Jingle XMPP VoIP extensions Skype protocol

SOURCE

https://en.wikipedia.org/wiki/Voice_over_IP

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What is Puppet used for?

What is Puppet used for?

• Advanced threat management
• Configuration management
• Remote desktop operations
• Backups and restores 

 

EXPLANATION

Puppet is an open-source configuration management tool that runs on Unix-like systems as well as on Microsoft Windows. It has its own declarative language that you can use to describe your system's configuration.

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When a user computer or device (like a cell phone, tablet, or printer) is having general, odd software problems, what is the most common easy fix?

When a user computer or device (like a cell phone, tablet, or printer) is having general, odd software problems, what is the most common easy fix?

• Turn it off and on again
• Update the drivers
• Attach a debugger to the port
• Replace the flash memory 

 

EXPLANATION

Computerized devices have become extremely complex in software and hardware interactions.
The highly interwoven tangle of software dependencies will frequently cause small memory leaks, resource contentions, and other unexpected results, cascading over time. Just like a deep cleaning in the kitchen is great for a chef to maintain food quality, a reboot is oftentimes the quickest and easiest way to get a misbehaving system to clear its slate and get back into an operating state.
Sadly, since the concept is so simple and seems inane, many users will not do it when instructed. Performing this quick and basic step first thing will often correct the original issue and if it doesn't (and the user complains they did it already), it still provides the benefit of starting troubleshooting with the knowledge that you're starting from a basic system state.

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