What does the sender need in order to digitally sign an email?

What does the sender need in order to digitally sign an email?

• The public key of the recipient
• The public key of the sender
• The private key of the recipient
• The private key of the sender 

EXPLANATION

A digital signature is created by hashing a message and encrypting the hash with the sender's private key. The recipient can then decrypt the hash with the sender's public key. The recipient's keys are not used for a digital signature.

The sender's public key is NOT required to sign the message.
The sender's public key (in the possession of the recipient) is used verify signature.
The recipient's public key is meaningless in this scenario.
The recipient's private key is meaningless in this scenario.  

A general overview of this process can be found here https://www.docusign.com/how-it-works/electronic-signature/digital-signature/digital-signature-faq

SOURCE

https://en.wikipedia.org/wiki/Public-key_cryptography#Digital_signatures

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In Windows, if you want to format a hard drive or removable disk so it can be read and written by both Windows and Apple machines you would format the disk as which of the following?

In Windows, if you want to format a hard drive or removable disk so it can be read and written by both Windows and Apple machines you would format the disk as which of the following?

• NTFS
• exFAT
• HFS
• REFS 

 

EXPLANATION

Both Windows and Apple machines can read drives formatted in FAT32.  Apple can read NTFS but cannot write to it.

SOURCE

https://www.laptopmag.com/articles/format-drive-for-windows-and-mac

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Which of these is an valid email address?

Which of these is an valid email address?

• All of them
• Michael.Scarn@[117.42.15.92]
• "dogs@r.com"@catsrule.com
• Security+@comptia.org 

 

EXPLANATION

Based on RFC 5322,
email address can have two "@" symbols as long as the first one is in quotation marks to identify the local name versus the domain name.  IP addresses can be used to identify the domain name.  The "+" symbol is valid in local names.

SOURCE

https://tools.ietf.org/html/rfc5322

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Which of the following technologies is required to run Hyper-V on Windows 2012 R2?

Which of the following technologies is required to run Hyper-V on Windows 2012 R2?

• DirectX
• Hyper-threading
• Hardware Enforced Data Execution Prevention (DEP)
• MMX4 

 

EXPLANATION

Hyper-V virtualization technology requires specific hardware. You can identify systems that support x64-based architecture and Hyper-V by searching the Windows Server Catalog for Hyper-V: Windows Server catalog.
Hyper-V Server has hardware requirements that are similar to those for the Hyper-V role in other editions of Windows Server. Hardware-enforced Data Execution Prevention (DEP) must be available and enabled. Specifically, you must enable the Intel XD (“execute disable”) bit or the AMD NX (“no execute”) bit.

SOURCE

https://technet.microsoft.com/en-us/library/cc731898(v=ws.11).aspx

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A standard rectangular male USB connector (for example, the connector on most mouse/ cables) is what type of connector?

A standard rectangular male USB connector (for example, the connector on most mouse/ cables) is what type of connector?

• USB Type C
• USB Type B
• Micro USB 3.0
• USB Type A 

EXPLANATION

A standard male USB
 connector for peripheral devices is known as a USB Type A Male connector.  Type B is the more squared or house shaped connector that is commonly used on printers or scanners to connect to a computer

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Which term from the past describes the sharing of mainframe computing resources?

Which term from the past describes the sharing of mainframe computing resources?

• XaaS
• Time-sharing
• Time division multiplexing
• Mainframe sharing 

 

EXPLANATION

Time-sharing allowed groups of people to use expensive mainframe computing resources concurrently by working in isolated computing sessions.
Time division multiplexing is a signal transmission protocol.
Mainframe sharing is not an industry-accepted term.
XaaS refers to any web service delivered over the Internet (Anything as a Service) and thus is incorrect

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In Linux, what's the difference between a hard link and a symbolic link?

In Linux, what's the difference between a hard link and a symbolic link?

• A hard link does not depend on software libraries, a soft link does.
• A hard link persists across OS reboots, a symbolic link does not.
• Normal users can use only symbolic links, only the "root" user can use hard links.
• A hard link points to a file's inode, a symbolic link is a pointer to the file. 

EXPLANATION

Symbolic links are much more common than hard links. They are aliases to an already existing file, and deleting the symbolic link will leave the existing file intact.
Renaming the file will break the link.  Hard links point to the very same filesystem inode used by the target file, so renaming the target file will have no effect on the hard link-- it will still point to the original file.  If for some reason the file targeted by a hard link is moved to a different spot in the filesystem, the hard link will no longer be valid.  Symbolic links are much more common than hard links.

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