Welcome To Technical Gyan

Protect your PC from virus & cyber attack.

2020-07-04T13:36:00.000+05:30

Hi Friends! Modern age is going towards digitization. Railway,Banking,Corporate,Education etc. are shifting towards digital platform.We can book tickets or can shop easily just in a click, even our surveillance system became strong by using digitization. We are using programming software. Mobile, Computers, IP cameras, Drones, Radars and many more resources are using on digital platform. Internet is the medium through which we have connected these resources & avail benefits. Softwares through which human & machines can connect & share data.But.. think a moment , are we safe? Out data is secure? no one watching us??? if yes then we should be aware.

Cyber crime may be happen & breach your data, it can disrupt your security & may be destroy your data. On these days we watch news related to "cyber crime happen in Australia.." NAHI was hit by ransomware attack suffered lose of data". Day to day we here these types of news. We need to be alert secure ourselves. So,our resources may not be tracked by hackers.

Awareness is key ingredient in success. So lets know How to Protect your PC from virus & cyber attack.

Must aware with Virus, Malware, Worm, Trojan horse, Spyware & other computer security breakers.

Turn on your computer Firewall. It is designed to actually filter threatening communication.I allows or block either inclusive of exclusive parameters. It is working like an access control list, which has particular set of guideline that allow or resist access to specific computer communication.

Keep your computer up to date.So that the OS patches will be up to date, it is just like the immunity booster for OS against the newly developed misbehavior programs.

Only download programs from websites that you trust. If you're not sure whether to trust a program that you want to download, enter the name of the program into your favorite search engine to see whether anyone else has reported that it contains spyware.

Read all security warnings,license agreements,and privacy statements that are associated with any software that you download.

Never click "Agree" or "OK" to close a window that you suspect might be spyware. Instead, click the red "x" in the corner of the window or press Alt + F4 on your keyboard to close a window.

Require employees to use strong passwords and change them periodically: A hacker may try to access your account more than once over a period of time. Changing your password reduces the risk that they will have frequent access. A keystroke logger is surveillance technology used to record keystrokes. Regularly changing your password makes it less likely that passwords obtained this way will be useful for any length of time.Keep your password length between 8-15 characters must be contains alphanumeric & special character.

Install anti-virus software: AV periodically scan your computer to keep protect your files, emails & web browsing activities. Antivirus gets update periodically & install updated virus definition.

Use email with caution: Users of email should be careful when they are using it. Hackers can exploit an email in many different ways; hiding viruses in attachments for example. It is very important to not open or read emails from email addresses you don’t recognize, they should be deleted from your inbox immediately.

Use internet carefully: Do you know even the safest website can contains spyware & malware, on a single click they can install in your computer. Avoid clicking on popups, ads, graphics and links to other websites.

Be Aware... Be Safe..😊😉😎

What is computer virus or malware?

2020-06-27T09:03:00.034+05:30

Computer Virus:-

Computer virus is a small program of malicious code, is written to alter the way of computer operation & spread it from one computer to another computer. It is similar to biological or flu virus which cannot reproduce without host cell. Computer virus spread through the programming files such as files or documents. It also spread by attachments in email messages or by instant messaging messages. Viruses can be disguised as attachments of funny images, greeting cards, or audio and video files. Computer viruses also spread through downloads on the Internet. They can be hidden in pirated software or in other files or programs that you might download.

A computer virus might corrupt or delete data on a computer, use an email program to spread the virus to other computers, or even delete everything on the hard disk. Stealing passwords or data, logging keystrokes, corrupting files, spamming your email contacts, and even taking over your machine are just some of the devastating and irritating things a virus can do.

Symptoms of virus active in your system:-

Pop-ups will appear frequently on your desktop:- Frequently pop-ups will appear on your computer screen & show you message that your computer need protection, download any fake antivirus or unwanted software. This may be due to any spyware available in computer or rogueware (Fake antivirus).
Computer running slow :- If suddenly your computer running slow. It may be a symbol of virus, Worm, Trojen , which running tasks which consume more space & slow down your computer.
Home page redirect automatically: - uhh hoooo.. my home page redirect automatically to another website.
Multiple tabs open when open web browser which neither is nor requested by you…
Cannot connect to the internet or internet is very slow….. Yes it may happen due to malware which, establish another session through your internet connectivity & you may face this issue.
My antivirus & firewall getting disappeared.. any program like this may be stop working of going to disappeared due to failure of some program in your computer, but when your all data security program disappear then you need to alert you are almost certainly infected.
Where have my data gone…..!!!! Usually no body asking these types of questions but.. Some types of thread may move your data from one location to other or encrypt them.

Till now you have familiar more words like Worm, Trojan horse, Spyware, Rouge ware, Malware etc.. so lets know these term.

What is worm?

Worm is a self replicating computer program that spreads without human interaction. Mostly it spreads from emails attachments that infect the computer when they are open. Worms uses system resources like hard drive & bandwidth by overloading a share network. It also steal data, install a backdoor and allow hackers to gain system control. So, keep monitoring your bandwidth , keep eyes on your hard drive, check time ti time for missing files of new files because worms delete and replace files in your computers.

What is spyware?

Spyware is a type of malware which can install on your computer without your knowledge. It can collect personal information secretly from your computer. Spyware can monitor your usually web browsing activity, it may install un necessary software in your system & guide your web browser according to him or may control your system.

What is a trojan horse?

Trojan horse is a malicious program is not spread by themselves but they spreads from virus, worms or downloaded software.It can spread like....You might think you’ve received an email from someone you know and click on what looks like a legitimate attachment. But you’ve been fooled. The email is from a cyber criminal, and the file you clicked on — and downloaded and opened — has gone on to install malware on your device.When you execute the program, the malware can spread to other files and damage your computer.

What is rogue security software?

A rogue security software program tries to make you think that your computer is infected by a virus and usually prompts you to download or buy a product that removes the virus. The names of these products frequently contain words like Antivirus, Shield, Security, Protection, or Fixer. This makes them sound legitimate. They frequently run right after you download them, or the next time that your computer starts. Rogue security software can prevent applications, such as Internet Explorer, from opening. Rogue security software might also display legitimate and important Windows files as infections.

What is malware?

Malware is a term that is used for malicious software that is designed to do damage or unwanted actions to a computer system. Examples of malware include the following:

Viruses
Worms
Trojan horses
Spyware
Rogue security software

👆How to Protect your PC from virus & cyber attack.

Security awareness is health for digitization.So, Guys....Be aware Be safe.!!!! 😊😊😊😊😊

IP Subnetting & CIDR

2020-06-24T21:10:00.001+05:30

What is IP Subnetting :-

IP Subnetting is a process of breaking a large network IP range to the small & reliable subnets. Subnets means the subnetwork of a large network. Subnet mask contains network & host portion. We acquire host portion to the network & perform subnetting. We know that one large network is not good thing so, we reduce the network congestion in our organization using subnetting.

Lets see an example of a large network :- 192.168.10.1/24 of class c default network, so the subnet mask is 255.255.255.0, now convert this decimal value into binary.

255 . 255 . 255 . 0

11111111 . 11111111 . 11111111 . 00000000

Network Bit Host Bit

All ones are on bits & represent network bit & all zeros are off bits represents as host bit. every octate have a maximum number is 255 in decimal, so, as per the above example there are 255 hosts available in the network range. suppose if we required only 25 hosts then our (255-30 = 225) IP will be waste.

We need subnetting to Organized our network, Reduce congestion & Prevent unused IP addresses.

Yes we will do subnetting but before that lets understand one more terms is CIDR.

Classless Inter-Domain Routing (CIDR) :-

CIDR is a slash (/) notation. When you receive any block of IP like 192.168.10.1/24 it is telling your subnet mask, slash notation means the on bits or the bits turns into 1's. In the block of 192.168.10.1/24, 24 bits are turned on.

There are 4 octate in ip address, 8 bits in each so total number of bits would be 8*4 = 32 . When we sunet any block there are 2 ip addresses are reserved first one for the Network address and Last one for Broadcast address, in the view of above till the /30 we have 4 ip addresses (2 are Network & Broadcast, other 2 are only valid host ip) so, practically to build a network we need 2 or more hosts & IPs. So, practically we can use only till /30 CIDR value.

Find the below subnet mask value for each slash notation CIDR value.

You can find out subnet mask for any slash (/) notation... as for example for /27 we have to find subnet mask so, we have already read IP class in last post What is IP address

if not please refer. So, /27 means there are 27 bits are on out of 32 like this:-

11111111.11111111.11111111. 1110 0 0 0 0

here we can see the power of 2 means 2^x. in last octate there are 5 bits are off means 0...... we will subtract the value from the 256.

11111111.11111111.11111111. 111 0 0 0 0 0

🠛 🠛 🠛 🠛 🠛

2⁵ = 32 2⁴ 2³ 2² 2¹= 2

We will count the power of two from right to left so the last off bit power of 2 is 32 so, minus this value from the 256. It will be 256-32= 224 so the subnet mask will be 255.255.255.240.

Now let's do subnetting in very easy steps.....!!! Think about these five points before subnet any IP block.

How many subnets does the chosen subnet mask produce?
How many valid hosts per subnet are available?
What are the valid subnets?
What’s the broadcast address of each subnet?
What are the valid hosts in each subnet?

Now let's subnet a block e.g 192.168.10.1/28, here /28 denote the total number of on bit out of 32 bits means total 1's.

11111111 . 11111111 . 11111111 . 11110000

Network Bit Host Bit

We are going to acquire host bit to the network bit since, it is a class C ip address so by default 24 bit allowed for network portion & we are going to acquire 4 more bits from the host portion, you can see in the highlighted text we have to check values from the portion from where we are acquiring bits.So................

1. How many subnets does the chosen subnet mask produce?

We will use formula 2^xhere x is the on bits or the masked bit. So, in our example check the highlighted portion there are 4 masked bits or ones so it is simple to find the number of subnets is...

2⁴= 2*2*2*2 =16 Subnets.

2. How many valid hosts per subnet are available?

We will use formula 2^y - 2 here y is off bit or all zeros.So, in our example check the highlighted portion there are 4 off bits or zeros so it is simple to find the number of hosts per subnets is...

2⁴ – 2 = 14 hosts per subnets

3. What are the valid subnets?

We can determined valid subnet by using formula 256-subnet mask so, it is 256- 240 (Subnet mask of /28 is 255.255.255.240) = 16 so, block starts with 0 then add 16 until 240.so it will be 0,16,32,48,64,80,96,112,128,144,160,176,192,208,224,240.

4. What’s the broadcast address of each subnet?

The broadcast address will be the number just before the next subnet number or the last number of current subnet block. lets check in our example we have already find the subnets in point number 3 so ,check the broadcast address of subnet 16 is 31, because the next subnet is 32..... broadcast address of 32 is 47.

5. What are the valid hosts in each subnet?

Valid hosts are always a group of numbers between the subnet & broadcast address, we have already find the both in point number 3 & 4 so lets find the valid hosts for first block 0 to 15 the valid hosts will be 1-14 means there are valid host range is 14, as it is for the next block 16 to 31 valid hosts will be 17-30............. yes its easy!!!!!

This is how we can subnet easily & find all the required details. For this class c subnet find all the details in below mentioned table:-

Thank you for reading... comment on post for any doubt....... 😊😉

CPU Central Processing Unit

2020-06-22T12:56:00.001+05:30

Processor/CPU Overview:-

Central processing unit understand all the activities between human & computer then, process the the instruction further as a command of a computer program by performing the basic arithmetical, logical, and input/output operations of the system.CPU is basically brain of computer, it stores data, immediate results & instructions.It performs all type of data processing operations.It controls the operations of all parts of the computer.

CPU has three main component:-

Memory or Storage Unit
Control Unit
ALU(Arithmetic Logic Unit)

Memory or Storage Unit

This unit can store instructions, data, and intermediate results. This unit supplies information to other units of the computer when needed. It is also known as internal storage unit or the main memory or the primary storage or Random Access Memory (RAM).Its size affects speed, power, and capability.

Primary memory and secondary memory are two types of memories in the computer. Functions of the memory unit are :-

It stores all the data and the instructions required for processing.
It stores intermediate results of processing.
It stores the final results of processing before these results are released to an output device.
All inputs and outputs are transmitted through the main memory.

Control Unit

This unit controls the operations of all parts of the computer but does not carry out any actual data processing operations.

Functions of this unit are :-

It is responsible for controlling the transfer of data and instructions among other units of a computer.
It manages and coordinates all the units of the computer.
It obtains the instructions from the memory, interprets them, and directs the operation of the computer.
It communicates with Input/output devices for transfer of data or results from storage.
It does not process or store data.

ALU (Arithmetic Logic Unit)

Arithmetic Section
Logic Section

Arithmetic Section

Function of arithmetic section is to perform arithmetic operations like addition, subtraction, multiplication, and division. All complex operations are done by making repetitive use of the above operations.

Logic Section

Function of logic section is to perform logic operations such as comparing, selecting, matching, and merging of data.

CPU Features :-

Speeds and Feeds :- Processor performance is usually a number in either MHz (megahertz) or GHz (gigahertz.) That number represents how many times the internal clock inside the CPU ticks in cycles per second. The clock inside a 2.5GHz CPU ticks 2.5 billion times each second.

But clock frequency isn’t a complete measure of performance. Efficiency — how much work can be done by the CPU in each clock cycle — is also important. This is measured in terms of instructions per cycle, often abbreviated as IPC. A CPU with a very high clock frequency, but low IPC, may not perform as well as a CPU with a lower clock frequency and high IPC.

Cache :- Fast access to memory is important to a PC processor, and that’s what your cache is for. Waiting for data to come in from system memory can make your CPU inefficient. The memory hierarchy is a way to show where memory bottlenecks exist. The CPU registers hold the data actually being used in calculations and comprise the fastest memory. The next fastest are levels 1 and 2 caches.

These are small amounts of fast memory built right onto the CPU core. Level 1 (L1) cache is faster but smaller than Level 2 (L2). Some CPUs have a third level, which is often shared between different CPU cores. Even the L3 cache is much faster than your computer’s main memory.

If an item of data is not in the cache, the CPU must wait until the data is retrieved from memory. In the slowest case, the data isn’t even in main memory, but must be fetched from the hard drive. However, while waiting for that data to be retrieved from system memory, the CPU can turn to a different task to help keep the PC running.

Cores:- Modern PC processors are multi core. Each core is as fully functional as the others. Each has its own cache, but can communicate with other CPU cores as needed. Cores can also share information in a cache, such as the level 3 cache built into AMD Phenom II processors. AMD’s Accelerated Processing Unit (APU) technology adds a new concept — the GPU core — which is better at certain kinds of math than the traditional core. The technology, originally developed for AMD’s Direct X 11-capable line of graphics cards, brings sophisticated graphics capability and parallel compute technology directly onto the CPU.

Current time you can see the cores like the mention below:-

Dual Core Processor (It has two cores)
Quad Core Processor (It has four cores)
Hexa Core Processor (It has six cores)
Octo Core Processor (It has eight cores)
Decca Core Processor (It has ten cores)

Bandwidth:- CPUs are part of a larger platform. They need to communicate with the outside world. Data buses (circuits that carry the data) communicate with the chip sets built onto the motherboard. The chips act as traffic cops to route data to the outside world, for example to the PCI Express slots, which communicate with discrete graphics cards and other expansion cards, and USB ports, which communicate with external storage, keyboards, mice, etc.

The speed of this communication is called bandwidth. It’s split into two types: memory and input/output (I/O). AMD processors have circuitry integrated into the CPU itself to handle all communication with system memory. This block of circuits is called the memory controller.

There are various companies manufactures processor but, below mentioned are the top processor manufacturing companies :-

Intel
AMD
Qualcomm
NVIDIA
IBM
Samsung
Motorola
Hewlett-Packard(HP)

Intel & AMD are the most demanding processor in current time. Choosing options & comparison between them:-

AMD Stands for Advance Micro Device was founded in 1969 & currently it is 2nd largest processor manufacturing company after Intel.AMD is said to offer the same basic product at the cheaper price than Intel.It consumption of power is more than Intel. AMD APUs made for gaming which contains CPU + GPU.AMD have low life/speed cpu's.

Intel Corporation was founded a year earlier in 1968 & its processors are costly than the AMD.Intel processors are power efficient.For gaming you need GPU which is not inbuilt in Intel processor but both the processor performs well for gaming. Intel have better cpu's life/speed like Core I7 (8 cores every core have 3Ghz speed).

Networking Devices

2020-06-21T19:41:00.001+05:30

Devices used in Networking:-

HUB:- Hub is centralized device, which is used to connect multiple workstations.It has no special kind of memory. It simply receives the frame (data) and forwards it to all its nodes except the receiving node. It always performs broadcasting. In case of hub, there is one collision domain and one broadcast domain. The media access method is used CSMA/CD (Carrier Sense Multiple Access/Collision Detection).

There are two types of Hub: -

Active Hub
Passive Hub

Active Hub:- In Active hub, it receives the frame regenerate and then forward to all its nodes. It increases the distance between devices, and it amplifies the signal and also the noise with it.

Passive Hub:-In Passive hub, it simply receives the frame and forward to all its connected nodes. It reduces the cabling distance by half because it doesn’t boost the signal and in fact absorbs some of the signal.

SWITCH:- Switch is also used to connect multiple workstations. Switch is more intelligent than hub. It has special kind of memory called mac address/filter/lookup table. Switch reads mac addresses. Switch stores mac addresses in its filter address table. Switch when receives frame, it reads the destination mac address and consult with its filter table. If he has entry in its filter table then he forwards the frame to that particular mac address, if not found then it performs broadcasting to all its connected nodes.

Every port has its own buffer memory. A port has two queues one is input queue and second is output queue. When switch receives the frame, the frame is received in input queue and forward from output queue. So in case of switch there is no chance or place for collisions. In case of switch, the media access method is used CSMA/CA (Carrier Sense Multiple Access/ Collision Avoidance). Switches provide more efficiency, more speed and security.

There are two types of switches: -

Manageable switches (can be configured with console cable).
Non-manageable switches.

BRIDGE:- Bridge is a hardware device, which is used to provide LAN segmentation means it is used for break the collision domain. It has same functionality as performed by switch. We can use bridge between two different typologies. It has fewer ports. Each port has a own buffer memory. It works on Data Link Layer of OSI model. It also read mac address and stores it in its filter table. In case of bridge there is one broadcast domain.

ROUTER:-Router is hardware device, which is used to communicate two different networks. Router performs routing and path determination. It does not perform broadcast information. Routers learn remote network information from neighboring router.Router then build routing table, which is basically map of interconnected network & it describe how to find remote network.

LAN CARD:- Lan card is media access device. Lan card provide us connectivity in the network. There is a RJ45 (Registered Jack) connector space on the Lan card. RJ45 is used in UTP cable. There is another led which is also called heartbeat of Lan card. When any activity occur it may be receiving or transmitting any kind of data. This led start blinking and also tell us the status of lan card.

Computer Tricks for day to day activity

2020-06-21T10:54:00.003+05:30

Tricks:-

Move the cursor quicker to the beginning of the previous word by pressing CTRL+Left Arrow, instead of doing it manually.
To get the cursor to the beginning of the next word, use CTRL+Right Arrow.
Recover a deleted item with ALT+Backspace.
Delete an entire word by pressing CTRL+Backspace.
Select a word you want to highlight quickly, without dragging the mouse, by double-clicking on it.
Highlight a whole paragraph by triple-clicking on it.
Make superscript and sub text by pressing CTRL + = for sub, and CTRL+ Shift for superscript.
Close all your windows quickly if you’re in a hurry by pushing the Windows button +D, and they will all shut immediately.
Rename your highlighted files quickly by pressing FN + F2.
Re-open your last closed tab with Shift + CTRL + T on most browsers.
Instead of moving the cursor to the close (X) in the corner, press CTRL + W to close the current window.
Take a screen shot with Windows + Print Screen.
Adjust any setting on your PC with the Windows “God Mode” folder, which is a centralized Control Panel for all the OS settings. Access this by creating a new folder named: God Mode.{ED7BA470-8E54-465E-825C-99712043E01C}.

Problem Step Recorder will record all mouse clicks and take screenshots. This tool is helpful to a tech when an issue with your PC needs to be diagnosed. Use this by pressing Windows + R then type the letters “psr” & press enter.

Start recording dialogue box will be open like this 👉

You may save or review the recording steps & screenshots also....

Enjoy Guys......😊

Check Internet speed on Taskbar

2020-06-20T15:57:00.001+05:30

How to Check Internet speed on Taskbar:-

Hello Guys!!! Generally we can check the speed of internet in our mobile phone but, not able to check in windows system. It is very easy to see now in windows machines. Let's do few steps..........

Step 1. We need to install a software. Download link is given below:-

👆Net Speed Monitor Software

Step 2. Open the download link & click on the Download now tab.

Step 3. Select the software size as your windows support.

Step 4. Double click on setup to install.... but,oops!!! there are an error message. Setup could not be install in the higher version of windows 8 & more.

Step 5. Right click on setup & go to property.

Step 6. Click on compatibility tab & check on "Run this program in compatibility mode for" Previous version of windows then click on Apply & Ok.

Step 7. Again double click on setup & let them install normally.

Step 8. Net Speed Monitor has been installed need few configuration to show on desktop. Right click anywhere on taskbar ➤ Toolbars ➤ NetSpeedMonitor.

Step 9. Yes guys!!! now you can see the Uplink & Downlink on your taskbar. Opps.. But speed is not monitored yet!!!!!!!

Step 10. Right click on the NetSpeedMonitored showing on taskbar & go to the connections. & Change or select your current connected internet driver. It may be WiFi of LAN on any other...

OK Guys Enjoy Now....!!!! 😊😊😊

How to see the password behind asterisk (*******)

2020-06-16T16:00:00.007+05:30

Hello Guys,

Now I am Gonna Show You How to Get Password Behind the Asterisk, that is *******

Firstly we know the meaning of Asterisk:-

An asterisk is the sign *. It is used especially to indicate that there is further information about something in another part of the text.

Follow the below steps:-

Step 1:- Firstly go to any login page in your web browser,(i have choose Facebook).

You can see here the password is saved under the Asterisk, and there are no any view option so you can click and view the password directly. Now, I will tell you the trick, how to see the password behind the Asterisk.

Step 2:- Right click on the page and go to the inspect....

Step 3:- Press control + F and type password

you can see here there are 8 times password Shaun in the the search bar. You have to select input Type password for any page may be other than Facebook.

Step 4:- Now just right click on the password found in yellow highlight and click on Add attribute.

Step 5:- Now double click on the passwords shown in yellow highlight and edit this "password" to the "text"

Finally guys it's working now..........

you can check in the asterisk ********change to the plain text and the password is visible now.

You May Also Watch:-

How to see password behind asterisk (*******) - https://youtu.be/Hn04o0bi8rY

How to hide drive without using any software - https://youtu.be/vqw2hy59USw

xxx

IP Addressing

2020-06-15T19:00:00.005+05:30

What is IP address ?

An IP address is a numeric identifier assigned to each machine on an IP network. It designates the specific location of a device on the network. An IP address is a software address, not a hardware address—the latter is hard-coded on a network interface card (NIC) and used for finding hosts on a local network. IP addressing was designed to allow hosts on one network to communicate with a host on a different network regardless of the type of LANs the hosts are participating in.

Types of IP Address

IPv₄(IP Version 4)

IPv₆(IP Version 6)

IPv₄(IP Version 4)

An IP address consists of 32 bits of information.These bits are divided into four sections referred to as octets or bytes, with each containing 1 byte (8 bits). You can depict an IP address using one of three methods:

· Dotted-decimal, as in 172.16.30.66

· Binary, as in 10101100.00010000.00011110.00111000

The 32-bit IP address is a structured or hierarchical address, as opposed to a flat or non hierarchical address. Although either type of addressing scheme could have been used, hierarchical addressing was chosen for a good reason. The advantage of this scheme is that it can handle a large number of addresses, namely 6.3 billion (a 32-bit address space with two possible values for each position—either 0 or 1—gives you 232, or 6,296,967,296). IPv4 is divided into classes.

classes

Network Address Range: Class A

The designers of the IP address scheme decided that the first bit of the first byte in a Class A

network address must always be off, or 0. This means a Class A address must be between 0 and 127 in the first byte, inclusive.Consider the following network address:

0xxxxxxx If we turn the other 7 bits all off and then turn them all on, we’ll find the Class A range of

network addresses:

00000000 = 0

01111111 = 127

So, a Class A network is defined in the first octet between 0 and 127, and it can’t be less or more. Understand that 0 and 127 are not valid in a Class A network because they’re reserved addresses, which I’ll explain soon.

Network Address Range: Class B

In a Class B network, the RFCs state that the first bit of the first byte must always be turned

on but the second bit must always be turned off. If you turn the other 6 bits all off and then all on, you will find the range for a Class B network:

10000000 = 128

10111111 = 191

As you can see, a Class B network is defined when the first byte is configured from 128 to 191.

Network Address Range: Class C

For Class C networks, the RFCs define the first 2 bits of the first octet as always turned on,

but the third bit can never be on. Following the same process as the previous classes, convert

from binary to decimal to find the range. Here’s the range for a Class C network:

11000000 = 192

11011111 = 223

So, if you see an IP address that starts at 192 and goes to 223, you’ll know it is a Class C IP address.

Network Address Ranges: Classes D and E

The addresses between 226 to 266 are reserved for Class D and E networks. Class D (226–239) is used for multicast addresses and Class E (260–266) for scientific purposes.

IPv6

Internet Protocol version 6 (IPv6) is the latest version of the Internet Protocol (IP), the communications protocol that provides an identification and location system for computers on networks and routes traffic across the Internet. IPv6 was developed by the Internet Engineering Task Force (IETF) to deal with the long-anticipated problem of IPv6 address exhaustion. IPv6 is intended to replace IPv6.

Every device on the Internet is assigned an IP address for identification and location definition. With the rapid growth of the Internet after commercialization in the 1990s, it became evident that far more addresses than the IPv6 address space has available were necessary to connect new devices in the future. By 1998, the Internet Engineering Task Force (IETF) had formalized the successor protocol. IPv6 uses a 128-bit address, allowing 2128, or approximately 3.6×1038 addresses, or more than 7.9×1028 times as many as IPv6, which uses 32-bit addresses and provides approximately 6.3 billion addresses. The two protocols are not designed to be interoperable, complicating the transition to IPv6. However, several IPv6 transition mechanisms have been devised to permit communication between IPv6 and IPv6 hosts.

IPv6 provides other technical benefits in addition to a larger addressing space. In particular, it permits hierarchical address allocation methods that facilitate route aggregation across the Internet, and thus limit the expansion of routing tables. The use of multicast addressing is expanded and simplified, and provides additional optimization for the delivery of services. Device mobility, security, and configuration aspects have been considered in the design of the protocol.

IPv6 addresses are represented as eight groups of four hexadecimal digits separated by colons, for example 2001:0db8:86a3:0062:1000:8a2e:0370:7336, but methods to abbreviate this full notation exist.

ipv6 conversion

OSI (Open Systems Interconnection) Model

2020-06-15T18:00:00.003+05:30

Open Systems Interconnection

OSI model is the layer approach to design, develop and implement network. OSI provides following advantages: -

Designing of network will be standard base.
Development of new technology will be faster.
Devices from multiple vendors can communicate with each other.
Implementation and troubleshooting of network will be easy.

1. Application Layer: -

Application layer accepts data and forward into the protocol stack. It creates user interface between application software and protocol stack.

2. Presentation Layer: -

This layer decides presentation format of the data. It also able to performs other function like compression/decompression and encryption/decryption.

3. Session Layer: -

This layer initiate, maintain and terminate sessions between different applications. Due to this layer multiple application software can be executed at the same time.

4. Transport Layer: -

Transport layer is responsible for connection oriented and connection less communication. Transport layer also performs other functions like

Error checking

Flow Control
Buffering
Windowing
Multiplexing
Sequencing
Positive Acknowledgement
Response

5. Network Layer

This layer performs function like logical addressing and path determination. Each networking device has a physical address that is MAC address. But logical addressing is easier to communicate on large size network.

Logical addressing defines network address and host address. This type of addressing is used to simplify implementation of large network. Some examples of logical addressing are: - IP addresses, IPX addresses etc.

6. Data Link Layer

The functions of Data Link layer are divided into two sub layers

Logical Link Control
Media Access Control

Logical Link Control defines the encapsulation that will be used by the NIC to delivered data to destination. Some examples of Logical Link Control are ARPA (Ethernet), 802.11 wi-fi.

Media Access Control defines methods to access the shared media and establish the identity with the help of MAC address. Some examples of Media Access Control are CSMA/CD, Token Passing.

7. Physical Layer

Physical Layer is responsible to communicate bits over the media this layer deals with the standard defined for media and signals. This layer may also perform modulation and demodulation as required.

Protocols

2020-06-15T17:00:00.003+05:30

Protocols

When two humans converse, they may have to use the same language but they generally understand each other without having to adhere to rigid rules of grammar or formal language frameworks. Computers, on the other hand, have to have everything explicitly defined and structured. If computers wish to communicate with one another, they have to know in advance exactly how information is to be exchanged and precisely what the format will be. Therefore, standard methods of transmitting and processing various kinds of information are used and these methods are called "protocols". Protocols are established by international agreement and ensure that computers everywhere can talk to one another. There are a variety of protocols for different kinds of information and functions. This article will discuss some of the common protocols that the average PC user is likely to encounter.

Types of protocols

HTTP (hyper text transfer protocol)

DNS (Domain Name server)

ARP(Address Resolution Protocol)

RARP(Reverse Address Resolution Protocol )

ICMP(Internal Controal Message Protocol)

TELNET(Telecommunication network)

DHCP(Dynamic Host Configuration Protocol)

FTP(File transfer Protocol)

TFTP(Trivial File Transfer Protocol)

POP-3(Post office Protocol)

IMAP(Internal Message Address Protocol)

SNMP(Simple network management Protocol)

SMTP(Simple Mail Transfer Protocol)

SSH(Server Shell)

Hypertext Transfer Protocol

Web pages are constructed according to a standard method called Hypertext Markup Language (HTML). An HTML page is transmitted over the Web in a standard way and format known as Hypertext Transfer Protocol (HTTP). This protocol uses TCP/IP to manage the Web transmission.

A related protocol is "Hypertext Transfer Protocol over Secure Socket Layer" (HTTPS), first introduced by Netscape. It provides for the transmission in encrypted form to provide security for sensitive data. A Web page using this protocol will have https: at the front of its URL.

File Transfer Protocol

File Transfer Protocol (FTP) lives up to its name and provides a method for copying files over a network from one computer to another. More generally, it provides for some simple file management on the contents of a remote computer. It is an old protocol and is used less than it was before the World Wide Web came along. Today, Its primary use is uploading files to a Web site. It can also be used for downloading from the Web but, more often than not, downloading is done via HTTP. Sites that have a lot of downloading (software sites, for example) will often have an FTP server to handle the traffic. If FTP is involved, the URL will have ftp: at the front.

Mail Protocols POP3 and SMTP

Email requires its own set of protocols and there are a variety, both for sending and for receiving mail. The most common protocol for sending mail is Simple Mail Transfer Protocol (SMTP). When configuring email clients, an Internet address for an SMTP server must be entered. The most common protocol used by PCs for receiving mail is Post Office Protocol(POP). It is now in version 3 so it is called POP3. Email clients require an address for a POP3 server before they can read mail. The SMTP and POP3 servers may or may not be the same address. Both SMTP and POP3 use TCP for managing the transmission and delivery of mail across the Internet.

A more powerful protocol for reading mail is Interactive Mail Access Protocol (IMAP). This protocol allows for the reading of individual mailboxes at a single account and is more common in business environments. IMAP also uses TCP to manage the actual transmission of mail.

ICMP

A different type of protocol is Internet Control Message Protocol (ICMP) . It defines a small number of messages used for diagnostic and management purposes. It is also used by Ping and Traceroute.

DNS

Domain Name System - translates network address (such as IP addresses) into terms understood by humans (such as Domain Names) and vice-versa

DHCP

Dynamic Host Configuration Protocol - can automatically assign Internet addresses to computers and users

FTP

File Transfer Protocol - a protocol that is used to transfer and manipulate files on the Internet

HTTP

HyperText Transfer Protocol - An Internet-based protocol for sending and receiving webpages

IMAP

Internet Message Access Protocol - A protocol for e-mail messages on the Internet

IRC

Internet Relay Chat - a protocol used for Internet chat and other communications

POP3

Post Office protocol Version 3 - a protocol used by e-mail clients to retrieve messages from remote servers

SMTP

Simple Mail Transfer Protocol - A protocol for e-mail messages on the Internet.

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Topology

2020-06-15T16:00:00.002+05:30

Network Topology:-

The physical topology of a network refers to the configuration of cables, computers, and other peripherals. Physical topology should not be confused with logical topology which is the method used to pass information between workstations.

Main Types of Physical Typologies

I. Linear Bus
II. Star
III. Tree (Expanded Star)
IV. Ring

Linear Bus:- A linear bus topology consists of a main run of cable with a terminator at each end . All nodes (file server, workstations, and peripherals) are connected to the linear cable.

linear bus topology

Advantages of a Linear Bus Topology

Easy to connect a computer or peripheral to a linear bus.

Requires less cable length than a star topology.

Disadvantages of a Linear Bus Topology

Entire network shuts down if there is a break in the main cable.

Terminators are required at both ends of the backbone cable.

Difficult to identify the problem if the entire network shuts down.

Not meant to be used as a stand-alone solution in a large building.

Star

A star topology is designed with each node (file server, workstations, and peripherals) connected directly to a central network hub, switch, or concentrator .

Data on a star network passes through the hub, switch, or concentrator before continuing to its destination. The hub, switch, or concentrator manages and controls all functions of the network. It also acts as a repeater for the data flow. This configuration is common with twisted pair cable; however, it can also be used with coaxial cable or fiber optic cable.

star topology

Advantages of a Star Topology

Easy to install and wire.

No disruptions to the network when connecting or removing devices.

Easy to detect faults and to remove parts.

Disadvantages of a Star Topology

Requires more cable length than a linear topology.

If the hub, switch, or concentrator fails, nodes attached are disabled.

More expensive than linear bus topologies because of the cost of the hubs, etc.

Tree or Expanded Star

A tree topology combines characteristics of linear bus and star topologies. It consists of groups of star-configured workstations connected to a linear bus backbone cable. Tree topologies allow for the expansion of an existing network, and enable schools to configure a network to meet their needs.

Tree topology

Advantages of a Tree Topology

Point-to-point wiring for individual segments.

Supported by several hardware and software venders.

Disadvantages of a Tree Topology

Overall length of each segment is limited by the type of cabling used.

If the backbone line breaks, the entire segment goes down.

More difficult to configure and wire than other topologies.

ring topology :

All devices are connected to one another in the shape of a closed loop, so that each device is connected directly to two other devices, one on either side of it. Ring topologies are relatively expensive and difficult to install, but they offer high bandwidth and can span large distances.

ring topology

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On Screen Keyboard Provided by Microsoft

2020-06-15T15:00:00.001+05:30

On Screen Keyboard Provided by Microsoft:-

Follow these steps:-

STEP 1:

Open "Run dialog box"(Use Win+R Key).

STEP 2:

Write "OSK" and Press "Enter"

What is Network?

2020-06-15T14:30:00.011+05:30

What Is Computer Network?

A network consists of two or more computers that are linked in order to share resources (such as printers and CDs), exchange files, or allow electronic communications. The computers on a network may be linked through mediums such as,cables, telephone lines, radio waves, satellites, or infrared light beams.

Types of network

         LAN(Local Area Network)
       WAN(Wide Area Network)
     MAN(Metropolitan Area Network)
   CAN(Campus Area Network)
   HAN(Home Area Network)

LAN :- A Local Area Network (LAN) is a network that is confined to a relatively small area. It is generally limited to a geographic area such as a writing lab, school, or building. Computers connected to a network are broadly categorized as servers or workstations. It is very simple to understand that the multi pal network resources are connected in same same network segment is called local area network.

WAN:- Wide Area Networks (WANs) connect networks in larger geographic areas, such as India, the United States, or the world. Dedicated transoceanic cabling or satellite up-links may be used to connect this type of global network. It uses multiplexers, bridges, and routers to connect local and metropolitan networks to global communications networks like the Internet.

CAN - The computers are within a limited geographic area, such as a campus or military base or school campus.

MAN:- A data network designed for a town or city.

HAN:- A network contained within a user's home that connects a person's digital devices such as, Laptop, TV, Mobile,Printers etc. You may connect personal digital devices through broadband connection.

Advantage of networking

User access control.

Modern networks almost always have one or more servers which allows centralized management for users and for network resources to which they have access. User credentials on a privately-owned and operated network may be as simple as a user name and password, but with ever-increasing attention to computing security issues, these servers are critical to ensuring that sensitive information is only available to authorized users.

Information storing and sharing.

Computers allow users to create and manipulate information. Information takes on a life of its own on a network. The network provides both a place to store the information and mechanisms to share that information with other network users.

Connections.

Administrators, instructors, and even students and guests can be connected using the campus network.

Services.

The school can provide services, such as registration, school directories, course schedules, access to research, and email accounts, and many others. (Remember, network services are generally provided by servers).

Internet.

The school can provide network users with access to the internet, via an internet gateway.

Computing resources.

The school can provide access to special purpose computing devices which individual users would not normally own. For example, a school network might have high-speed high quality printers strategically located around a campus for instructor or student use.

Flexible Access.

School networks allow students to access their information from connected devices throughout the school. Students can begin an assignment in their classroom, save part of it on a public access area of the network, then go to the media center after school to finish their work. Students can also work cooperatively through the network.

Work-group Computing.

Collaborative software allows many users to work on a document or project concurrently. For example, educators located at various schools within a county could simultaneously contribute their ideas about new curriculum standards to the same document, spreadsheets, or website.

Disadvantage of networking

Expensive to Install.

Large campus networks can carry hefty price tags. Cabling, network cards, routers, bridges, firewalls, wireless access points, and software can get expensive, and the installation would certainly require the services of technicians. But, with the ease of setup of home networks, a simple network with internet access can be setup for a small campus in an afternoon.

Requires Administrative Time.

Proper maintenance of a network requires considerable time and expertise. Many schools have installed a network, only to find that they did not budget for the necessary administrative support.

Servers Fail.

Although a network server is no more susceptible to failure than any other computer, when the files server "goes down" the entire network may come to a halt. Good network design practices say that critical network services (provided by servers) should be redundant on the network whenever possible.

Cables May Break.

The Topology chapter presents information about the various configurations of cables. Some of the configurations are designed to minimize the inconvenience of a broken cable; with other configurations, one broken cable can stop the entire network.

Security and compliance.

Network security is expensive. It is also very important. A school network would possibly be subject to more stringent security requirements than a similarly-sized corporate network, because of its likelihood of storing personal and confidential information of network users, the danger of which can be compounded if any network users are minors. A great deal of attention must be paid to network services to ensure all network content is appropriate for the network community it serves.

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Privet Browsing/incognito Tab

2020-06-15T13:03:00.001+05:30

Privet Browsing/incognito Tab

You know that if u want to browse something on web without being noticed by anyone, you can do it by using an option in various browsers,I will tell u how to use it :-

For Google Chrome :-

1.click on menu button of chrome.

2.A new window will be appear,click on "New incognito window" & enjoy privet browsing.

Now you are in ur privet window

FOR Firefox :-

1.click on menu button

2.Then click on "New privet window"

DONE!!!!!!!!

Hide Drives Without Using Any Software

2020-06-14T17:04:00.007+05:30

Hide Drives Without Using Any Software

Hi friends now u can hide your drivers without using any software.In our computer labs we see only "C" drive and think that there are no drivers are available except "C" drive,but all drivers are hidden by lab in charge...
Let see how to hide drivers without using any software :-

Press window + R key.
Open gpedit.msc

A new window will be appear as Local Group Policy Editor.

Click & expand User Configuration >Administrative Templates > Windows Component

After Double click on Windows component on the right side bar Windows Explorer (for window 7 & xp) File Explorer (for window 8,8.1 & 10)
Now click on Hide These Specified drives in My computer.
Click on Enable then choose below the drives you want to hide on Pick one of the following combination.
Then click Apply & Ok.

For Unhide Drive follow the same steps, In step 7 just click on Not Configure then apply & OK

Thank you.

Make Folder Without Name in Windows 7,8,8.1 & 10

2013-07-10T17:09:00.026+05:30

Follow The Following Steps:-

Make a folder anywhere in your computer,where you want.
Right click & select rename option.
Press alt key with numeric 255 (You may type 0106 also) from numeric keyboard & release alt key.
Press 🠈Enter key or click any where.

You can check now your folder be like without name.

Thank you guys!!! Subscribe my blog for new technical gyan. 😊

Message From Me

2013-07-10T00:15:00.027+05:30

To became successful in life never stop learning. Success doesn’t just find you. you have to go out and get it. This blog is very easily explain about technical gyan, every post explain steps by steps to learn you easily so, go through the blog & enhance your technical skills by learning computer tricks & networking theories. As you know, sometimes later becomes never. Do it now.

From My Pen 🖋

Welcome To Technical Gyan

Protect your PC from virus & cyber attack.

What is computer virus or malware?

Computer Virus:-

Symptoms of virus active in your system:-

👆How to Protect your PC from virus & cyber attack.

IP Subnetting & CIDR

CPU Central Processing Unit

Processor/CPU Overview:-

CPU Features :-

Networking Devices

Devices used in Networking:-

Computer Tricks for day to day activity

Tricks:-

Check Internet speed on Taskbar

How to Check Internet speed on Taskbar:-

How to see the password behind asterisk (*******)

IP Addressing

What is IP address ?

OSI (Open Systems Interconnection) Model

Open Systems Interconnection

Protocols

Protocols

Types of protocols

Topology

Network Topology:-

The physical topology of a network refers to the configuration of cables, computers, and other peripherals. Physical topology should not be confused with logical topology which is the method used to pass information between workstations.

Main Types of Physical Typologies

I. Linear BusII. StarIII. Tree (Expanded Star)IV. Ring

Linear Bus:- A linear bus topology consists of a main run of cable with a terminator at each end . All nodes (file server, workstations, and peripherals) are connected to the linear cable. linear bus topology

Advantages of a Linear Bus Topology

Easy to connect a computer or peripheral to a linear bus. Requires less cable length than a star topology.

Disadvantages of a Linear Bus Topology

Entire network shuts down if there is a break in the main cable. Terminators are required at both ends of the backbone cable. Difficult to identify the problem if the entire network shuts down. Not meant to be used as a stand-alone solution in a large building.

Star

Advantages of a Star Topology

Easy to install and wire. No disruptions to the network when connecting or removing devices. Easy to detect faults and to remove parts.

Disadvantages of a Star Topology

Requires more cable length than a linear topology. If the hub, switch, or concentrator fails, nodes attached are disabled. More expensive than linear bus topologies because of the cost of the hubs, etc.

Tree or Expanded Star

Advantages of a Tree Topology

Point-to-point wiring for individual segments. Supported by several hardware and software venders.

Disadvantages of a Tree Topology

Overall length of each segment is limited by the type of cabling used. If the backbone line breaks, the entire segment goes down. More difficult to configure and wire than other topologies.

ring topology :

On Screen Keyboard Provided by Microsoft

What is Network?

What Is Computer Network?

Types of network

LAN(Local Area Network) WAN(Wide Area Network) MAN(Metropolitan Area Network) CAN(Campus Area Network) HAN(Home Area Network)

CAN - The computers are within a limited geographic area, such as a campus or military base or school campus.

MAN:- A data network designed for a town or city.

HAN:- A network contained within a user's home that connects a person's digital devices such as, Laptop, TV, Mobile,Printers etc. You may connect personal digital devices through broadband connection.

Advantage of networking

Disadvantage of networking

Privet Browsing/incognito Tab

Privet Browsing/incognito Tab

Now you are in ur privet window

Hide Drives Without Using Any Software

Make Folder Without Name in Windows 7,8,8.1 & 10

Message From Me

I. Linear Bus
II. Star
III. Tree (Expanded Star)
IV. Ring

Linear Bus:- A linear bus topology consists of a main run of cable with a terminator at each end . All nodes (file server, workstations, and peripherals) are connected to the linear cable.

linear bus topology

Easy to connect a computer or peripheral to a linear bus.

Requires less cable length than a star topology.

Entire network shuts down if there is a break in the main cable.

Terminators are required at both ends of the backbone cable.

Difficult to identify the problem if the entire network shuts down.

Not meant to be used as a stand-alone solution in a large building.

Easy to install and wire.

No disruptions to the network when connecting or removing devices.

Easy to detect faults and to remove parts.

Requires more cable length than a linear topology.

If the hub, switch, or concentrator fails, nodes attached are disabled.

More expensive than linear bus topologies because of the cost of the hubs, etc.

Point-to-point wiring for individual segments.

Supported by several hardware and software venders.

Overall length of each segment is limited by the type of cabling used.

If the backbone line breaks, the entire segment goes down.

More difficult to configure and wire than other topologies.

LAN(Local Area Network)
WAN(Wide Area Network)
MAN(Metropolitan Area Network)
CAN(Campus Area Network)
HAN(Home Area Network)