IT Questions and Answers :)

Tuesday, April 30, 2019

What is/was the purpose for using a Dynamic Disk Overlay?

What is/was the purpose for using a Dynamic Disk Overlay?

  • Software to increase existing disk drives speed.
  • Software to hide a disk drive from hackers.
  • A dust cap for the disk drive to be used when cleaning the system.
  • Software technique to extend a system BIOS that does not support logical block addressing (LBA). 

 
What is/was the purpose for using a Dynamic Disk Overlay?

EXPLANATION


Dynamic drive overlay (DDO, also referred to as: software translation driver) is a software technique to extend a system BIOS that does not support logical block addressing (LBA) to access drives larger than 504 MiB. The technology was continued with similar types of problems up to the LBA-48 extension.

The most widespread vendor for such an extension is the company Ontrack which is licensing its DDO component to several of the major hard disk vendors for integration into their management tools and into their products.
The application of a Dynamic Drive Overlay (DDO), as licensed to Samsung Corporation for example, by Kroll Ontrack's version in their Disk Manager program is for the installation of various hard drives (Ultra/Super IDE/Parallel ATA) in computers that have older BIOS chips that do not recognize hard disk drives larger than 137.4 Gigabytes.[1] The interface is a software program that is loaded at start-up by the computer and augments the BIOS code, thus allowing the system to recognize and read areas of the hard disk drive that normally would not be accessible by the older BIOS.

This technique overrides some of the motherboard BIOS' hard disk controller driver in RAM. To allow access to the full size of any hard disk the software must be loaded before other programs try to access the upper parts of a disk with a critical size. To ensure that this extension gets loaded early most often the boot disk's master boot record is modified and the software installed at the beginning of the disk.

SOURCE

https://en.wikipedia.org/wiki/Dynamic_drive_overlay
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Friday, April 26, 2019

What settings in VMware would you use to keep VMs together or separate?

What settings in VMware would you use to keep VMs together or separate?

  • Affinity rules
  • NSX
  • VDS
  • Snapshots 

 
What settings in VMware would you use to keep VMs together or separate?

EXPLANATION


An affinity rule is a setting that establishes a relationship between two or more VMware virtual machines (VMs) and hosts.
Affinity rules and anti-affinity rules tell the vSphere hypervisor platform to keep virtual entities together or separated. The rules, which can be applied as either required or preferred, help reduce traffic across networks and keep the virtual workload balanced on available hosts.
If two virtual machines communicate frequently and should share a host, the VMware admin can create a VM-VM affinity rule to keep them together. Conversely, if two resource-hungry VMs would tax a host, an anti-affinity rule will keep those VMs from sharing a host.
Affinity rules and anti-affinity rules can be applied between VMs and hosts as well, and a VM can be subject to VM-VM affinity rules and VM-Host affinity rules at the same time. Affinity and anti-affinity rules in a vSphere environment can conflict with one another. For example, two VMs with an anti-affinity relationship may both be linked to a third VM via an affinity rule, but they cannot share a host. Optional affinity rule violation alarms can alert administrators to these events.

SOURCE

https://searchvmware.techtarget.com/definition/affinity-rules
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In Windows, how do you enter ASCII characters that are not displayed on a keyboard?

In Windows, how do you enter ASCII characters that are not displayed on a keyboard?

Ctrl-Alt + keyboard keys corresponding to ASCII
Alt + ASCII decimal value on number pad
Shift-Alt + keyboard keys cooresponding to ASCII
Alt + ASCII decimal value using keyboard top 

 

EXPLANATION

I have used Alt + ASCI decimal value entered on the number pad for many years for various reasons.  It's a nice way to hide characters in passwords or files you want to keep secure. A password with an Alt-255 (null) character will display as a space and baffle even the most experienced hacker. While working in a public school system, my remote software client was VNC and it stored the password in hexidecimal format in the registry which above average students might
possibly be able to decode. But when ASCII 255 characters are found, they're totally confused. I have also named programs and batch files with just the null character plus extension to make it hidden.  I have also used ASCII extended box and line characters to make things look nicer in batch programs, but is limited with newer versions of Windows that lack ANSI.sys not being standard (it can be enabled).

SOURCE

https://support.office.com/en-us/article/insert-ascii-or-unicode-latin-based-symbols-and-characters-d13f58d3-7bcb-44a7-a4d5-972ee12e50e0
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Wednesday, April 24, 2019

What do you dial to bring up the IMEI number on a mobile phone?

What do you dial to bring up the IMEI number on a mobile phone?

  • #69#*
  • *#123#
  • *#06#
  • #044*# 

What do you dial to bring up the IMEI number on a mobile phone?

EXPLANATION

Every phone or Mobile Broadband device has a unique 15 digit code, called an IMEI number. You might need to find your IMEI number if you want to unlock your device to use with other networks, or for some
insurance policies. You can find your IMEI in the following ways: by entering *#06# on your phone's call screen.

SOURCE

http://support.three.co.uk/SRVS/CGI-BIN/WEBISAPI.dll/,/?New,Kb=Mobile,Ts=Mobile,T=CaseDoc,Case=Obj(6589)
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Which operating system for Exchange 2019 is unsupported:

Which operating system for Exchange 2019 is unsupported:

  • Windows Server 2008 R2
  • Windows Server 2012 R2
  • All of them
  • Windows Server 2012 
Which operating system for Exchange 2019 is unsupported:

EXPLANATION

The supported operating system for Exchange 2019 is only Windows Server 2019 Standard or Datacenter. Windows Server 2019 Core edition is
also fully supported and recommended.

SOURCE

https://docs.microsoft.com/en-us/exchange/plan-and-deploy/system-requirements?view=exchserver-2019#operating-system
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Tuesday, April 23, 2019

In CSS, which one of these symbols is the child selector?

In CSS, which one of these symbols is the child selector?

  • -
  • +
  • >
In CSS, which one of these symbols is the child selector?

EXPLANATION

The greater-than symbol ">" is the child selector in CSS and is written between two elements, the first element being the parent and the second element being the child. From the W3Schools website,
"The child selector selects all elements that are the immediate children of a specified element."

SOURCE

https://www.w3schools.com/css/css_combinators.asp

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Monday, April 22, 2019

What is the command to restart IIS services on the command line?

What is the command to restart IIS services on the command line?

  • iisrestart
  • iisreset
  • iisrecycle
  • iisrefresh 

What is the command to restart IIS services on the command line?

EXPLANATION

An IIS server can be restarted without rebooting the entire machine by running the iisreset command on the command line.  There is a button on the IIS management console that can also do this; additionally, you can manually restart the services involved.


Take IISReset as a suite of commands that helps you manage IIS start / stop etc.
Which means you need to specify option (/switch) what you want to do to carry any operation.
Default behavior OR default switch is /restart with iisreset so you do not need to run command twice with /start and /stop.
Hope this clarifies your question. Check this MS DOS help picture you will understand.



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I have some private servers on my premises, also I have distributed some of my workload on the public cloud, what is this architecture called?

I have some private servers on my premises, also I have distributed some of my workload on the public cloud, what is this architecture called?

  • Hybrid Cloud
  • Private Cloud
  • Public Cloud
  • Virtual Private Cloud 

 
I have some private servers on my premises, also I have distributed some of my workload on the public cloud, what is this architecture called?

EXPLANATION

This type of architecture would be a hybrid cloud. Why? Because we are using both, the public cloud, and your on premises servers i.e the private cloud. To make this hybrid architecture easy to use, wouldn’t it be better if your private and public cloud were all on the same
network(virtually). This is established by including your public cloud servers in a virtual private cloud, and connecting this virtual cloud with your on premise servers using a VPN(Virtual Private Network).

SOURCE

https://www.edureka.co/blog/interview-questions/top-aws-architect-interview-questions-2016/
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Which of these would manually trigger a synchronization for Azure AD Connect through PowerShell?

Which of these would manually trigger a synchronization for Azure AD Connect through PowerShell?

  • start-adsyncsynccycle -policytype alfa
  • start-adsyncsynccycle -policytype delta
  • start-adsyncsynccycle -policytype all
  • start-adsyncsynccycle 
Which of these would manually trigger a synchronization for Azure AD Connect through PowerShell?

EXPLANATION

You can still force an export by using the synchronization service manager.
A server in staging mode continues to receive changes from Active Directory and Azure AD. It always has a copy of the latest changes and can very fast take over the responsibilities of another server.
If you make configuration changes to your primary server, it is your responsibility to make the same changes to the server in staging mode.
start-adsyncsynccycle -policytype delta

SOURCE

https://docs.microsoft.com/en-us/azure/active-directory/connect/active-directory-aadconnectsync-operations
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What command does someone type in a terminal session in Linux to turn it into a superuser session?

What command does someone type in a terminal session in Linux to turn it into a superuser session?

  • sudo -i
  • chmod
  • wget
  • chkdsk 

EXPLANATION

 chmod In Unix-like operating systems, is the command and system call which may change the access permissions to file system objects. It may also alter special mode flags. The request is filtered by the umask. The name is an abbreviation of change mode.



Wget is a computer program that retrieves content from web servers. It is part of the GNU Project. Its name derives from World Wide Web and get. It supports downloading via HTTP, HTTPS, and FTP
CHKDSK is a system tool in DOS, OS/2 and Windows. It verifies the file system integrity of a volume and fixes logical file system errors. It is similar to the fsck command in Unix.
sudo is a program for Unix-like computer operating systems that allows users to run programs with the security privileges of another user, by default the superuser. It originally stood for "superuser do" as the older versions of sudo were designed to run commands only as the superuser.
 
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What keyboard combination allows you to restore out of a Windows remote desktop session back to your desktop so you can use Alt + Tab to switch apps on your desktop, not the RDP session and then allows you to restore to full screen RDP again?

What keyboard combination allows you to restore out of a Windows remote desktop session back to your desktop so you can use Alt + Tab to switch apps on your desktop, not the RDP session and then allows you to restore to full screen RDP again?

  • Ctrl Alt Tab
  • Ctrl Shift Tab
  • Ctrl Alt Break
  • Alt Shift Break 


EXPLANATION

Pressing Ctrl + Alt + Fn + B maximizes the RDP session.

SOURCE

https://answers.microsoft.com/en-us/windows/forum/windows_7-desktop/rdp-full-screen-wo-break-pause-key/0aba31a9-b375-443b-8066-a57d41ea333c 
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I have keys but do not lock. I have space but have no room. You can enter but not come in what am I?

I have keys but do not lock. I have space but have no room. You can enter but not come in what am I?

  • Hard Drive
  • The Riddler
  • Keyboard
  • Windows

EXPLANATION

I have keys but no locks I have space but no room You can enter but cant go outside. Thank you for visiting our website. Below you will be able to find all I have keys but no locks I have space but no room You can enter but cant go outside . This is an excellent riddle which is tricky at the same time.

SOURCE

 https://www.answersking.com/i-have-keys-but-no-locks-i-have-space-but-no-room-you-can-enter-but-cant-go-outside/

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In Windows, what is the run command to bring up programs/apps list?

In Windows, what is the run command to bring up programs/apps list?

  • appwiz.cpl
  • appwiz.msc
  • appmgr.cpl
  • appmgr.dll 


EXPLANATION

Appwiz.cpl is a Windows shortcut that allows you to launch the installed programs window without going through the Control Panel. The installed programs window contains programs and applications that you can uninstall and remove safely without damaging your computer.

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Which is NOT a supported version of .NET Framework on any release of Exchange 2019?

Which is NOT a supported version of .NET Framework on any release of Exchange 2019?

  • .NET Framework 4.7.1
  • .NET Framework 4.5
  • All of them
  • .NET Framework 4.6.2 

Which is NOT a supported version of .NET Framework on any release of Exchange 2019?

EXPLANATION

.NET Framework

We strongly recommend that you use the latest version of the .NET Framework that's supported by the release of Exchange you're installing.

Important

Releases of .NET Framework that aren't listed in the table below aren't supported on any release of Exchange 2019. This includes minor and patch-level releases of .NET Framework.

Exchange version .NET Framework 4.7.2
Exchange 2019 Supported

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What does IT stand for in IT Administrator ?

What does IT stand for in IT Administrator ?

  • Information Technology
  • Integrated Timeline
  • Income Tax
  • Industrial Trainee 

 What does IT stand for in IT Administrator ?

EXPLANATION

Income tax
An income tax is a tax imposed on individuals or entities that varies with respective income or profits. Income tax generally is computed as the product of a tax rate times taxable income. Taxation rates may vary by type or characteristics of the taxpayer.
 
Information technology
Information technology is the use of computers to store, retrieve, transmit, and manipulate data, or information, often in the context of a business or other enterprise. IT is considered to be a subset of information and communications technology.

 

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Which of the following is Stack structure?

Which of the following is Stack structure?

  • LILO (Last In Last Out)
  • FILO (First In Last Out)
  • LIFO (Last In First Out)
  • LIFO (Last In First Out) 
Which of the following is Stack structure?

EXPLANATION

 Stack Stands for "First In, Last Out." FILO is an acronym used in computer science to describe the order in which objects are accessed. It is synonymous with LIFO (which is more commonly used) and may also be called LCFS or "last come, first served."

A stack is a typical data structure that may be accessed using the LIFO method. In a stack, each item is placed on top of the previous item, one at a time. Items can be removed from either the top of the stack (FILO) or from the bottom of the stack FIFO.
You can imagine a FILO stack as the paper in a printer tray. Whatever paper you place on top of the existing paper in the input tray will be accessed first.
FILO is not necessarily a "fair" way to access data, since it operates in opposite order of a queue. Still, the FILO method can be useful for retrieving recently used objects, such as those stored in cache memory.
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OSI model is having how many layers?

OSI model is having how many layers?

  • 7
  • 6
  • 2
 OSI model is having how many layers?

EXPLANATION

The Open Systems Interconnection model is a conceptual model that characterizes and standardizes the communication functions of a telecommunication or computing system without regard to its underlying internal structure and technology. Its goal is the interoperability of diverse communication systems with standard protocols. The model partitions a communication system into abstraction layers. The original version of the model defined seven layers.

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Which Microsoft product was code named Snowball?

Which Microsoft product was code named Snowball?

  • Windows 95
  • Windows Vista
  • Windows Server 2016
  • Windows For Workgroups 3.11 
 Which Microsoft product was code named Snowball?


EXPLANATION

Operating systems

Windows 3.1x and 9x

Codename Preliminary name Final name Notes Ref
Janus N/A Windows 3.1 N/A [2][3]
Sparta, Winball Windows Plus Windows for Workgroups 3.1 Windows 3.1 (16-bit) with enhanced networking; designed to work particularly well as a client with the new Windows NT. [4][5]
Snowball Windows for Workgroups 3.10 Windows for Workgroups 3.11 Although this release was still 16-bit Windows, it included a 32-bit TCP/IP stack (when running on compatible hardware). Along with Win32s, this was one of the first steps towards moving the Windows desktop to a 32-bit code base. [6]
Chicago Windows 4.0 Windows 95 For codenames of some of the internal components of Windows 95, see "Jaguar", "Cougar", "Panther" and "Stimpy" under § OS components. [7][8]
Detroit Windows 4.1 Windows 95 OSR 2 Named after Detroit, Michigan. A writer for Maximum PC suggested that "Detroit" and other Windows 95-era names were answers to the question posed by Microsoft's "Where do you want to go today?" marketing campaign. [9]
Nashville Windows 96 N/A Cancelled upgrade for Windows 95; sometimes referred to in the press as Windows 96. Codename was reused for Internet Explorer 4.0 and Windows Desktop Update which incorporated many of the technologies planned for Nashville. [10][11]
Memphis Windows 97, Windows 4.1 Windows 98 N/A [12]
Millennium Windows 4.9 Windows ME ME stands for Millennium Edition.

 

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What are the types of Eavesdropping attacks?

What are the types of Eavesdropping attacks?

  • Passive & Active
  • Data driven & software written
  • Right & Wrong
  • malicous & outbound 

What are the types of Eavesdropping attacks?

EXPLANATION

Eavesdropping attacks occur through the interception of network traffic. By eavesdropping, an attacker can obtain passwords, credit card numbers and other confidential information that a user might be sending over the network. Eavesdropping can be passive or active:
  • Passive eavesdropping — A hacker detects the information by listening to the message transmission in the network.
  • Active eavesdropping — A hacker actively grabs the information by disguising himself as friendly unit and by sending queries to transmitters. This is called probing, scanning or tampering.
Detecting passive eavesdropping attacks is often more important than spotting active ones, since active attacks requires the attacker to gain knowledge of the friendly units by conducting passive eavesdropping before.
Data encryption is the best countermeasure for eavesdropping.

SOURCE

https://blog.netwrix.com/2018/05/15/top-10-most-common-types-of-cyber-attacks/#Eavesdropping%20attack
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In telecommunications, what does DIA stand for?

In telecommunications, what does DIA stand for?

  • Dynamic Internet Access
  • Digital Internet Access
  • Direct Internet Access
  • Dedicated Internet Access 


EXPLANATION

 These are data center applications which might require your company to need a Dedicated Internet Access (DIA) circuit, instead of the average, cost-effective business Internet access types, like Fios, U-verse, business-class cable, and DSL.

Types of Dedicated Internet Access circuits include:
Dedicated Fiber (a.k.a. fast ethernet, metro ethernet, ethernet over fiber); Ethernet over Copper (EoC); T-1 (DS-1); T-3 (DS-3); and Dedicated Fixed-Wireless.
The type of DIA circuit your company needs, depends on the circuit types available at your address and the bandwidth your company requires. In theory, the type of DIA circuit (i.e. fiber vs. T-1), only affects the bandwidth and price of the Internet connection.

SOURCE

 https://acronyms.thefreedictionary.com/dia

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On ESXi, how is the parent-child relation determined between the base disk file and it's delta files, when a snapshot of a VM is taken.

On ESXi, how is the parent-child relation determined between the base disk file and it's delta files, when a snapshot of a VM is taken.

  • Through VMFS metadata
  • Through ESXi database
  • Through .vmx file
  • Through .vmdk descriptor file 

On ESXi, how is the parent-child relation determined between the base disk file and it's delta files, when a snapshot of a VM is taken.

EXPLANATION

 Delta disk files: A .vmdk file to which the guest operating system can write. The delta disk represents the difference between the current state of the virtual disk and the state that existed at the time that the previous snapshot was taken. When you take a snapshot, the state of the virtual disk is preserved, which prevents the guest operating system from writing to it, and a delta or child disk is created. A delta disk has two files, including a descriptor file that is small and contains information about the virtual disk and a corresponding file that contains the raw data. The files that make up the delta disk are referred to as child disks or redo logs.


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What is the name of Microsoft's virtualization suite?

What is the name of Microsoft's virtualization suite?

  • Hyper-V
  • VM Ware
  • Viridian
  • Windows Server Virtualization 
What is the name of Microsoft's virtualization suite?

EXPLANATION

VMware
vmware.comVMware, Inc. is a subsidiary of Dell Technologies that provides cloud computing and platform virtualization software and services. It was the first commercially successful company to virtualize the x86 architecture.
Hyper-V

Microsoft Hyper-V, codenamed Viridian and formerly known as Windows Server Virtualization, is a native hypervisor; it can create virtual machines on x86-64 systems running Windows. Starting with Windows 8, Hyper-V superseded Windows Virtual PC as the hardware virtualization component of the client editions of Windows NT. A server computer running Hyper-V can be configured to expose individual virtual machines to one or more networks.
Type:Native hypervisor
Included with:Windows Server 2008 and later, Select editions of Windows 8 and later
Replaces:Windows Virtual PC

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What is the longest run of UTP cable allowed for a single segment connection?

What is the longest run of UTP cable allowed for a single segment connection?

  • 110 to 150 meters
  • 90 to 100 Meters
  • 100 to 105 meters
  • 80 to 89 meters 

EXPLANATION

UTP cable does not have a maximum length.
However, the protocol that runs over UTP has a maximum length for performance and technical reasons (such as collision detection in Ethernet).

You're probably talking about Ethernet, and the maximum end-to-end cable length in Ethernet (at least for 100Base-TX, 1000Base-T and 10GBase-T) is 100M.

Assuming you're running full-duplex, you're withing spec (and hence should be fine) as long as no switch-switch or switch-host connection exceeds 100M.



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What is the port for HTTPS?

What is the port for HTTPS?

  • Port 434
  • Port 444
  • Port 440
  • Port 443 
 What is the port for HTTPS?

EXPLANATION

HTTPS

(HyperText Transport Protocol Secure) The protocol used to access a secure Web server. When https:// is used as the prefix of a Web address rather than the common http://, the session is managed by a security protocol, typically TLS, which superseded SSL, and the transmission is encrypted to and from the Web server. Increasingly, all websites use HTTPS;
for example, in 2015, Wikipedia switched to HTTPS. For details about the HTTP protocol, see HTTP. To learn about the security protocol, see TLS and security protocol. See HSTS and HTTPS Everywhere.

 Port 443 PortTCP - HTTPS (Hypertext Transfer Protocol over SSL/TLS)


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Sunday, April 21, 2019

What is the port for HTTP?

What is the port for HTTP?

  • Port 443
  • Port 225
  • Port 20
  • Port 80 

What is the port for HTTP?

EXPLANATION

Port 443
HTTP Secure is an extension of the Hypertext Transfer Protocol for secure communication over a computer network, and is widely used on the Internet. In HTTPS, the communication protocol is encrypted using Transport Layer Security, or formerly, its predecessor, Secure Sockets Layer. The protocol is therefore also often referred to as HTTP over TLS, or HTTP over SSL.



 Port 80 is the port number assigned to commonly used internet communication protocol, Hypertext Transfer Protocol (HTTP). It is the port from which a computer sends and receives Web client-based communication and messages from a Web server and is used to send and receive HTML pages or data

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The basis of internet is?

The basis of internet is?

  • TPC.PI
  • PCT/IP.
  • IP/ITC.
  • TCP/IP. 

The basis of internet is?

EXPLANATION

  1. DEFINITION • A communication system that connect computers and computer networks all over the world . It helps us to surf information on various topics, play online games, etc.
  2.  Internet is interconnection of large number of heterogeneous computer networks all over the world that can share information back and forth. These interconnected network exchange information by using same standards and protocols • It allows people to send and receive data wherever they are in the world if they have internet access
  3. TYPES OF NETWORK • There are three main types of network: • LAN (local area network) • MAN (metropolitan area network) • WAN (wide area network)
  4. USES OF INTERNET 1) Communication 2) Job searches 3) Bussiness use of internet 4) Travel 5) Health and medicine 6) Online booking . 7) Social networking. 8) Online shopping. 9) Video conferencing. 10) Stock markey updates 11) Games and songs 12)Easy access to information.
  5. Communication • It is used for sending and receiving message from one and other through internet by using electronic mail. Some of the web sites providing this service are yahoomail.com Hotmail.com rediffmail.com etc
  6.   Job searches Getting information regarding availability of job in different sectors and areas. You can publish your resume in online for prospective job. Some of the web sites providing this service are naukri.com, monster.com, summerjob.com, recuritmentindia.com etc.
  7.   Business use of internet• Different ways by which intenet can be used for business are: • • Information about the product can be provided online to the the customer . • • Provide market information to the business • • It help business to recruit talented people • Some examples: www.cleverbusinesswebsites.co.uk • https://www.godaddy.com
  8.   Traveling • One can use internet to gather information about various tourist place . it can be used for booking Holiday tours , hotels, train and flights. Some of the web sites providing this service are: indiatravelog.com, rajtravel.com, makemytrip.com.
  9.   Health and medicine: • Internet provide information and knowledge about field of health medicine people can have information about various disease and can receive help .patient can be taken to virtual check room where they can meet doctors. Some of the web sites providing this service are: www.indianhealthcenter.org, www.uwmedicine.org/
  10.   ONLINE BOOKING • We can book movie tickets, sports tickets online. We can book railway tickets, Airlines, hotels, bus tickets and much more through internet.For exmple-bookmyshow.com, www.kyazoonga.com
  11.   SOCIAL NETWORKING  Social networking websites function like an online community of internet users. Depending on the website in question, many of these online community members share common interests in hobbies, religion, politics and alternative lifestyles.   Some common sites are facebook, twitter, flickr, my space and YouTube.
  12.   ONLINE SHOPPING • We can buy mobiles, books, digital cameras, gifts, fashion jewellery, computers, laptops, watches and other products at best price. • Some common websites are : flipkart.com, letsbuy.com, indiaplaza.com etc.
  13.   VIDEO CONFERENCING Web conferencing refers to a service that allows conferencing events to be shared with remote locations. In general the service is made possible by Internet technologies, particularly on TCP/IP connections. It offers information of text-based messages, voice and video chat to be shared simultaneously, across geographically dispersed locations. For example- www.lifesize.com/
  14.   Stock market updates • You can sell or buy shares while sitting on computer through internet. Several websites like ndtvprofit.com, moneypore.com, provide information regarding investment
  15.   GAMES AND SONGS • We can play online games on internet. • We can listen any music, watch movies and download it from different web stores. • Such as, utorrent, songs.pk and beemp3 etc.
  16.   Easy to access information Through internet we can collect information on any topic. Any information is easily available on the internet .for example – google,wikipedia,y ahoo,bingetc
  17.   Some other uses are : • Finding books and study material • On-line Journals,Magazines,Enclopedia and Dictionary. • Software sharring. For example- techlanda.com

 

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The default Time-To-Live (TTL) value for IP packets differs based on operating system. What is the default TTL value in Windows?

The default Time-To-Live (TTL) value for IP packets differs based on operating system. What is the default TTL value in Windows?

  • 128
  • 255
  • 32
  • 64
The default Time-To-Live (TTL) value for IP packets differs based on operating system. What is the default TTL value in Windows?

EXPLANATION

You can find your own TTL value from your self.

RUN->CMD->ping 127.0.0.1

C:\>ping 127.0.0.1

Pinging 127.0.0.1 with 32 bytes of data:
Reply from 127.0.0.1: bytes=32 time<1ms TTL=128
Reply from 127.0.0.1: bytes=32 time<1ms TTL=128
Reply from 127.0.0.1: bytes=32 time<1ms TTL=128
Reply from 127.0.0.1: bytes=32 time<1ms TTL=128

Ping statistics for 127.0.0.1:
    Packets: Sent = 4, Received = 4, Lost = 0 (0% loss),
Approximate round trip times in milli-seconds:
    Minimum = 0ms, Maximum = 0ms, Average = 0ms

C:\>


As you can see from the output, you got the TTL value. Since this website is hosted on a Red Hat system, it returned 57 which is close to 64 (TTL default value of Linux system). So, from this we can understand the OS of the remote system. Here are the default TTL values of different devices / Operating Systems :

Device / OS Version Protocol TTL
AIX TCP 60
AIX UDP 30
AIX 3.2, 4.1 ICMP 255
BSDI BSD/OS 3.1 and 4.0 ICMP 255
Compa Tru64 v5.0 ICMP 64
Cisco ICMP 254
DEC Pathworks V5 TCP and UDP 30
Foundry ICMP 64
FreeBSD 2.1R TCP and UDP 64
FreeBSD 3.4, 4.0 ICMP 255
FreeBSD 5 ICMP 64
HP-UX 9.0x TCP and UDP 30
HP-UX 10.01 TCP and UDP 64
HP-UX 10.2 ICMP 255
HP-UX 11 ICMP 255
HP-UX 11 TCP 64
Irix 5.3 TCP and UDP 60
Irix 6.x TCP and UDP 60
Irix 6.5.3, 6.5.8 ICMP 255
juniper ICMP 64
MPE/IX (HP) ICMP 200
Linux 2.0.x kernel ICMP 64
Linux 2.2.14 kernel ICMP 255
Linux 2.4 kernel ICMP 255
Linux Red Hat 9 ICMP and TCP 64
MacOS/MacTCP 2.0.x TCP and UDP 60
MacOS/MacTCP X (10.5.6) ICMP/TCP/UDP 64
NetBSD ICMP 255
Netgear FVG318 ICMP and UDP 64
OpenBSD 2.6 & 2.7 ICMP 255
OpenVMS 07.01.2002 ICMP 255
OS/2 TCP/IP 3.0 64
OSF/1 V3.2A TCP 60
OSF/1 V3.2A UDP 30
Solaris 2.5.1, 2.6, 2.7, 2.8 ICMP 255
Solaris 2.8 TCP 64
Stratus TCP_OS ICMP 255
Stratus TCP_OS (14.2-) TCP and UDP 30
Stratus TCP_OS (14.3+) TCP and UDP 64
Stratus STCP ICMP/TCP/UDP 60
SunOS 4.1.3/4.1.4 TCP and UDP 60
SunOS 5.7 ICMP and TCP 255
Ultrix V4.1/V4.2A TCP 60
Ultrix V4.1/V4.2A UDP 30
Ultrix V4.2 – 4.5 ICMP 255
VMS/Multinet TCP and UDP 64
VMS/TCPware TCP 60
VMS/TCPware UDP 64
VMS/Wollongong 1.1.1.1 TCP 128
VMS/Wollongong 1.1.1.1 UDP 30
VMS/UCX TCP and UDP 128
Windows for Workgroups TCP and UDP 32
Windows 95 TCP and UDP 32
Windows 98 ICMP 32
Windows 98, 98 SE ICMP 128
Windows 98 TCP 128
Windows NT 3.51 TCP and UDP 32
Windows NT 4.0 TCP and UDP 128
Windows NT 4.0 SP5- 32
Windows NT 4.0 SP6+ 128
Windows NT 4 WRKS SP 3, SP 6a ICMP 128
Windows NT 4 Server SP4 ICMP 128
Windows ME ICMP 128
Windows 2000 pro ICMP/TCP/UDP 128
Windows 2000 family ICMP 128
Windows Server 2003 128
Windows XP ICMP/TCP/UDP 128
Windows Vista ICMP/TCP/UDP 128
Windows 7 ICMP/TCP/UDP 128
Windows Server 2008 ICMP/TCP/UDP 128
Windows 10 ICMP/TCP/UDP 128

I will update this table in the future when there’s a release of new important OS whenever I get the time. You can get the short version of default TTL values by this table :

Device / OS TTL
*nix (Linux/Unix) 64
Windows 128
Solaris/AIX 254


 

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What is the correct syntax to run a error fixing check disk in a command prompt?

What is the correct syntax to run a error fixing check disk in a command prompt?

  • chkdsk /f
  • cd
  • ipconfig
  • dir 

EXPLANATION

 The cd command, also known as chdir, is a command-line OS shell command used to change the current working directory in operating systems such as Unix, DOS, OS/2, AmigaOS, Windows, and Linux. It is also available for use in shell scripts and batch files. The system call that affects the command in most operating systems is chdir that is defined by POSIX.



In computing, ipconfig in Microsoft Windows is a console application that displays all current TCP/IP network configuration values and can modify Dynamic Host Configuration Protocol and Domain Name System settings.

In computing, dir is a command used for file and directory listing, specifically in the command line interface of the operating systems CP/M, DOS, OS/2, Singularity, Microsoft Windows and in the DCL command line interface used on VMS, RT-11 and RSX-11. The command is also supplied with OS/8 as a CUSP. 

Checks the file system and file system metadata of a volume for logical and physical errors. If used without parameters, chkdsk displays only the status of the volume and does not fix any errors. If used with the /f, /r, /x, or /b parameters, it fixes errors on the volume.

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