In the early days of computer technology, what type of memory had to be hand made rather than by machine?

In the early days of computer technology, what type of memory had to be hand made rather than by machine?

• Thin film memory
• EPROM
• Magnetic core memory
• Bubble Memory 

 

EXPLANATION

Magnetic core memory was almost always "woven" by hand in spite of repeated attempts to automate the process. Core uses tiny magnetic beads (the cores), through which wires are threaded to write and read information.

SOURCE

https://en.wikipedia.org/wiki/Magnetic-core_memory

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Which is the standard file extension used by VMWare for virtual hard drive images?

Which is the standard file extension used by VMWare for virtual hard drive images?

• VHD (Virtual Hard Disk)
• VDI (Virtual Disk Image)
• VMDK (Virtual Machine Disk)
• HDD (Hard Disk Drive) 

 

EXPLANATION

VMDK is the standard used by VMWare and is supported by several other virtual hypervisors.  It can contain the entire virtual machine, including settings.
VHD is the standard typically used by Microsoft Hyper-V.  It represents a single virtual drive, and does not contain configuration settings for the rest of the virtual machine.
HDD is the standard for Parallels.
VDI is the standard and default for type-2 hypervisor VirtualBox; it can use and create all four of the listed formats, however.

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What is the minimum size of the IPv6 packet header?

What is the minimum size of the IPv6 packet header?

• 36 octets
• 32 octets
• 40 octets
• 48 octets 

 

EXPLANATION

The IPv6 packet header has a minimum size of 40 octets. Options are implemented as extensions. This provides the opportunity to extend the protocol in the future without affecting the core packet structure.
RFC 2460; Internet Protocol, Version 6 (IPv6) Specification, S. Deering, R. Hinden (December 1998)
https://en.wikipedia.org/wiki/IPv6

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In MacOS, what terminal command will temporarily reduce the frequency of the "spinning beach ball" icon caused by a RAM shortage?

In MacOS, what terminal command will temporarily reduce the frequency of the "spinning beach ball" icon caused by a RAM shortage?

• purge ram
• purge mem
• sudo purge
• sudo clearmem 

 

EXPLANATION

Purging the memory clears on inactive memory allocation, thus making it usable to applications. Sudo purge accomplishes this.

SOURCE

http://osxdaily.com/2012/04/24/free-up-inactive-memory-in-mac-os-x-with-purge-command/

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Which of the following is NOT a PowerShell comparison operator type?

Which of the following is NOT a PowerShell comparison operator type?

• Matching
• Containment
• Replacement
• Assignment

 
 

EXPLANATION

Comparison operators are used in PowerShell to compare values. There are four types of operators: equality, matching, containment, and replacement. The one big gotcha in PowerShell has to do with syntax: rather than using traditional comparison operators like < or > PowerShell uses -lt or -gt to perform comparisons.

SOURCE

https://docs.microsoft.com/en-us/powershell/module/microsoft.powershell.core/about/about_comparison_operators?view=powershell-5.1

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Two organizations are partnering and sharing systems. Which of the following would outline how the shared systems interface?

Two organizations are partnering and sharing systems. Which of the following would outline how the shared systems interface?

• BPA
• SLA
• ISA
• ROA 

 

EXPLANATION

An interconnection security agreement (ISA) documents the technical requirements of a connection between organizations,
such as the basic components, methods and levels of interconnectivity, and potential security risks.

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You need to encrypt and compress your backups before replicating them off site. Which is best practice, compress then encrypt, or encrypt then compress?

You need to encrypt and compress your backups before replicating them off site. Which is best practice, compress then encrypt, or encrypt then compress?

• Neither!
• Encrypt first!
• Doesn't matter!
• Compress first! 

 

EXPLANATION

If you encrypt the data first, it will be randomized and unintelligible by your compression application which need to compress the data in a logical format.  

Compressing then encrypting is the way to go.

SOURCE

https://stackoverflow.com/questions/4676095/when-compressing-and-encrypting-should-i-compress-first-or-encrypt-first 

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