In the world of VoIP, SIP works primarily in which layer of the OSI model?

In the world of VoIP, SIP works primarily in which layer of the OSI model?

• Layer 4: transportation layer
• Layer 5: session layer
• Layer 2: data link layer
• Layer 7: application layer 

EXPLANATION

A Session Initiation Protocol (SIP) operates on the application layer. The basic purpose of SIP is to establish communications over the internet.
These communications might include video conferencing, online gaming or audio calls. It makes use of the idea of Voice over IP (VoIP) to achieve this purpose. It can create, modify and terminate these communication sessions. However, SIP also makes use of other transfer protocols such as TCP and UDP and does not operate entirely on its own.

 

Read More

Malware is best defined as...

Malware is best defined as...

• Software designed to infiltrate or damage a PC
• Program designed to protect the Operating System
• Microsoft Arithmetic LAN Software
• Software run in the background of any Windows OS

EXPLANATION

A definition of malware. “Malware” is short for “malicious software” - computer programs designed to infiltrate and damage computers without the users consent. “Malware” is the general term covering all the different types of threats to your computer safety such as viruses, spyware, worms, trojans, rootkits and so on.

 

Read More

When it comes to IT Security, what does APT stand for?

When it comes to IT Security, what does APT stand for?

• Automatic Package Transfer
• Advanced Persistent Threat
• Advanced Packaging Tool
• Applied Computing Toolkit 

EXPLANATION

An advanced persistent threat (APT) is a prolonged and targeted cyberattack in which an intruder gains access to a network and remains undetected for an period of time. The intention of an APT attack is usually to monitor network activity and steal data rather than to cause damage to the network or organization.

 

Read More

What is the default Unix shell in macOS?

What is the default Unix shell in macOS?

• tcsh
• bash
• ksh
• zsh 

EXPLANATION

If you did a new or clean install of OS X version 10.3.x, the default user shell is bash. Bash is essentially an enhanced and GNU freeware version of the original Bourne shell, sh. Unless you happen to like bash, I recommend either switching to tcsh or zsh.

Starting with macOS Catalina, Macs will now use zsh as the default login shell and interactive shell across the operating system. All newly created user accounts in macOS Catalina will use zsh by default 

Read More

In Linux, the root account is associated with which UID?

In Linux, the root account is associated with which UID?

• 1
• 0
• 6
• 4

EXPLANATION

Usually, the root user account is called root . However, in Unix and Linux, any account with user id 0 is a root account, regardless of the name. It is fairly common for certain system administrators to have their own root accounts on a system, with their own passwords.

 

Read More