The Live Migration process with Hyper-V refers to which of the following?

The Live Migration process with Hyper-V refers to which of the following?

• Moving VMs from one physical host to another
• Reassigning user rights to different virtual machines
• Moving physical servers to a different part of a data centre
• Upgrading the server OS on a host machine 

EXPLANATION

Live migration refers to the process of moving a running virtual machine or application between different physical machines without disconnecting the client or application. Memory, storage, and network connectivity of the virtual machine are transferred from the original guest machine to the destination.

 
Hyper-V live migration is a Microsoft Hyper-V feature that allows administrators to move virtual machines (VMs) between clustered hosts without noticeable service interruption.

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Which of the following is an interpreted language?

Which of the following is an interpreted language?

• C#
• Java
• C++
• Python 

EXPLANATION

Most programs are written in a high-level language such as C, Perl, or Java. Just as a human language makes it easy for people to communicate with one another, so computer languages simplify the job of telling a computer what to do. However, because a computer only understands numbers, talking to one is like speaking to someone with whom you don't share a language. You need a translator to properly communicate, and that's what interpreters and compilers do.
The difference between an interpreted and a compiled language lies in the result of the process of interpreting or compiling. An interpreter produces a result from a program, while a compiler produces a program written in assembly language. The assembler of architecture then turns the resulting program into binary code. Assembly language varies for each individual computer, depending upon its architecture. Consequently, compiled programs can only run on computers that have the same architecture as the computer on which they were compiled.
A compiled program is not human readable, but instead is in an architecture-specific machine language. Creating a compiled program requires several steps. First, the programmer, using a development tool or even a simple text editor, writes the source code in a chosen computer language. If the program is complex, pieces of it may be spread across several files. The programmer then compiles the program, sorting and linking the modules and translating it all into machine code that the computer understands.
Because different kinds of computers do not speak each others' machine languages, a compiled program will only work on the platform it was designed for. For example, a program written for HP-UX normally will not work on a Mac OS computer or a computer running Solaris. Despite this drawback, compiled programs are faster than those that must be run through an interpreter. Also, it is often possible to recompile the program so that it will run on different platforms. Examples of languages that are normally used to produce compiled programs include C, Fortran, and COBOL.
In an interpreted program, on the other hand, the source code typically is the program. Programs of this type (often known as scripts) require an interpreter, which parses the commands in the program and then executes them. Some interpreters, such as the Unix shells (sh, csh, ksh, etc.), read and then immediately execute each command, while others, such as Perl, analyze the entire script before sending the corresponding machine language instructions. The advantage of a script is that it is very portable. Any computer that has the appropriate interpreter installed may run the program more or less unchanged. This is a disadvantage as well, because the program will not run at all if the interpreter is not available. In general, interpreted programs are slower than compiled programs, but are easier to debug and revise. Other examples of interpreted languages include JavaScript and Python.
Intermediate to computer-specific compiled programs and interpreted scripts are programs designed for runtime environments. Java and Smalltalk programs are executed in this fashion. Constructing programs for runtime environments is similar to writing traditional compiled programs. The difference is that instead of compiling the source code into a machine language, it is output into byte code for the runtime environment's "virtual machine". This virtual machine intercepts the byte code instructions and translates them into computer-specific commands. The advantage of this approach is that the runtime environment quickly compiles only the needed pieces of the code (some parts of the program may never need to be executed). This is called just-in-time compiling. The major disadvantage with runtime environments is that a program that is not designed well will force the runtime environment to compile almost all of the code up front and then make redundant calls to the interpreter. This makes the program slower to load and run.

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When it comes to hardware, what does CMOS stand for?

When it comes to hardware, what does CMOS stand for?

• Complementary Metal Oxide Semiconductor
• Carbon Magnesium Oxide Silicon
• Complete Memory Onboard System
• Computer Memory On Semiconductor 

EXPLANATION

CMOS. Stands for "Complementary Metal Oxide Semiconductor." It is a technology used to produce integrated circuits. CMOS circuits are found in several types of electronic components, including microprocessors, batteries, and digital camera image sensors

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Linux is named after:

Linux is named after:

• Linus Pauling
• Linus van Pelt
• Linus Sebastian
• Linus Torvalds 

EXPLANATION

Torvalds was named after Linus Pauling, the Nobel Prize-winning American chemist, although in the book Rebel Code: Linux and the Open Source Revolution, Torvalds is quoted as saying, "I think I was named equally for Linus the Peanuts cartoon character", noting that this makes him half "Nobel Prize-winning chemist" and half "blanket-carrying cartoon character.

Linus Torvalds had wanted to call his invention Freax, a portmanteau of "free", "freak", and "x" (as an allusion to Unix). During the start of his work on the system, he stored the files under the name "Freax" for about half of a year. ... So, he named the project "Linux" on the server without consulting Torvalds

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When it comes to security, what does IDS stand for?

When it comes to security, what does IDS stand for?

• Intrusion Defense System
• Integrated Delivery System
• Integrated Deterrence System
• Intrusion Detection System 

EXPLANATION

Intrusion Detection System (IDS)

An Intrusion Detection System (IDS) is a system that monitors network traffic for suspicious activity and issues alerts when such activity is discovered. It is a software application that scans a network or a system for harmful activity or policy breaching. Any malicious venture or violation is normally reported either to an administrator or collected centrally using a security information and event management (SIEM) system. A SIEM system integrates outputs from multiple sources and uses alarm filtering techniques to differentiate malicious activity from false alarms.
Although intrusion detection systems monitor networks for potentially malicious activity, they are also disposed to false alarms. Hence, organizations need to fine-tune their IDS products when they first install them. It means properly setting up the intrusion detection systems to recognize what normal traffic on the network looks like as compared to malicious activity.
Intrusion prevention systems also monitor network packets inbound the system to check the malicious activities involved in it and at once sends the warning notifications.
Classification of Intrusion Detection System:
IDS is basically classified into 2 types:

1. Network Intrusion Detection System (NIDS):
   Network intrusion detection systems (NIDS) are set up at a planned point within the network to examine traffic from all devices on the network. It performs an observation of passing traffic on the entire subnet and matches the traffic that is passed on the subnetts to the collection of known attacks. Once an attack is identified or abnormal behavior is observed, the alert can be sent to the administrator. An example of an NIDS is installing it on the subnet where firewalls are located in order to see if someone is trying crack the firewall.


2. Host Intrusion Detection System (HIDS):
   Host intrusion detection systems (HIDS) run on independent hosts or devices on the network. A HIDS monitors the incoming and outgoing packets from the device only and will alert the administrator if suspicious or malicious activity is detected. It takes a snapshot of existing system files and compares it with the previous snapshot. If the analytical system files were edited or deleted, an alert is sent to the administrator to investigate. Anexample of HIDS usage can be seen on mission critical machines, which are not expected to change their layout.

Detection Method of IDS:

1. Signature-based Method:
   Signature-based IDS detects the attacks on the basis of the specific patterns such as number of bytes or number of 1’s or number of 0’s in the network traffic. It also detects on the basis of the already known malicious instruction sequence that is used by the malware. The detected patterns in the IDS are known as signatures. Signature-based IDS can easily detect the attacks whose pattern (signature) already exists in system but it is quite difficult to detect the new malware attacks as their pattern (signature) is not known.
   
2. Anomaly-based Method:
   Anomaly-based IDS was introduced to detect the unknown malware attacks as new malware are developed rapidly. In anomaly-based IDS there is use of machine learning to create a trustful activity model and anything coming is compared with that model and it is declared suspicious if it is not found in model. Machine learning based method has a better generalized property in comparison to signature-based IDS as these models can be trained according to the applications and hardware configurations.

Comparison of IDS with Firewalls:
IDS and firewall both are related to the network security but an IDS differs from a firewall as a firewall looks outwardly for intrusions in order to stop them from happening. Firewalls restrict access between networks to prevent intrusion and if an attack is from inside the network it don’t signal. An IDS describes a suspected intrusion once it has happened and then signals an alarm.

 

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