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New, syllabus, 2020-21, Chapter 10, Network security, Concepts, , Computer Science, Class XII ( As per CBSE Board), Visit : python.mykvs.in for regular updates

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Network Security Concepts, Network security is the process of physical and, software preventative measures to protect the, networking infrastructure from unauthorized access,, malfunction, destruction, misuse, modification, or, improper disclosure, thereby creating a secure platform, for computers, users, and programs to perform their, permitted critical functions within a secure, environment., , Visit : python.mykvs.in for regular updates

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Network Security Concepts, Network security threats types:, • Passive Network Threats: Passive cyber attacks employ nondisruptive methods so that the hacker does not draw attention to, the attack. Passive attacks are usually data gathering operations,, which means they usually employ some sort of malware or hack, that eavesdrops on system communications Activities such as, wiretapping and idle scans that are designed to intercept traffic, traveling through the network., • Active Network Threats: Active cyber attacks are often aggressive,, blatant attacks that victims immediately become aware of when, they occur. Activities such as Denial of Service (DoS) attacks and, SQL injection attacks where the attacker is attempting to execute, commands to disrupt the network’s normal operation. Viruses,, worms,Trojan horse,spam,malware, Denial of Service attacks, and, password crackers are all examples of active cyber attacks., Visit : python.mykvs.in for regular updates

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Network Security Concepts, Computer virus -, , is a malicious software program loaded onto a user's computer without the, user's knowledge and performs malicious actions., COMMON TYPES OF COMPUTER VIRUSES, 1. RESIDENT VIRUS-Resident viruses set up in RAM and meddle with system operations. They’re so, sneaky that they can even attach themselves to anti-virus software files., 2. MULTIPARTITE VIRUS-This virus infects the entire system. Multipartite viruses spread by performing, unauthorized actions on operating system, folders, and programs., 3. DIRECT ACTION-This virus targets a specific file type, most commonly executable files (.exe), by, replicating and infecting files. Due to its targeted nature, this virus type is one of the easier ones to, detect and remove., 4. BROWSER HIJACKER-Easily detected, this virus type infects browser and redirects you to malicious, websites., 5. OVERWRITE VIRUS-Like the name implies, overwrite viruses overwrite file content to infect entire, folders, files, and programs., 6. WEB SCRIPTING VIRUS-This sneaky virus disguises itself in the coding of links, ads, images, videos, and, site code. It can infect systems when users download malicious files or visit malicious websites., 7. FILE INFECTOR-By targeting executable files (.exe), file infector viruses slow down programs and, damage system files when a user runs them., 8. NETWORK VIRUS-Network viruses travel through network connections and replicate themselves, through shared resources., 9. BOOT SECTOR VIRUS-One of the easier viruses to avoid, this virus hides out in a file on a USB drive or, email attachment. When activated, it can infect the system’s master boot record to damage the system., , Visit : python.mykvs.in for regular updates

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Network Security Concepts, , Ways to prevent from computer virus –, • Open Emails, Even Coming From Friends,, Carefully, • Install Anti-virus Software and Keep it up to, Date, • Scan System Regularly, • Browse Safely, • Download Files Carefully, Visit : python.mykvs.in for regular updates

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Network Security Concepts, A computer worm - is a malicious, self-replicating software program, (popularly termed as 'malware') which affects the functions of software and, hardware programs., Different types of Computer Worms are:, • Email Worms: Email Worms spread through infected email messages as an, attachment or a link of an infected website., • Instant Messaging Worms: Instant Messaging Worms spread by sending, links to the contact list of instant messaging applications., • Internet Worms: Internet worm will scan all available network resources, using local operating system services and/or scan the Internet for vulnerable, machines. If a computer is found vulnerable it will attempt to connect and, gain access to them., • IRC Worms: IRC Worms spread through IRC chat channels, sending, infected files or links to infected websites., • File-sharing Networks Worms: File-sharing Networks Worms place a copy, of them in a shared folder and spread via P2P network., Visit : python.mykvs.in for regular updates

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Network Security Concepts, Ways to prevent from computer worms, • Since software vulnerabilities are major infection vectors, for computer worms, be sure that computer’s operating, system and applications are up to date with the latest, versions. Install these updates as soon as they’re available, because updates often include patches for security flaws., • Phishing is another popular way for hackers to spread, worms Always be extra cautious when opening unsolicited, emails, especially those from unknown senders that contain, attachments or dubious links., • Be sure to invest in a strong internet security software, solution that can help block computer worms., Visit : python.mykvs.in for regular updates

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Network Security Concepts, A Trojan horse - or Trojan, is a type of malicious code or software that looks legitimate, but can take control of computer. A Trojan is designed to damage, disrupt, steal, or in, general inflict some other harmful action on data or network., Types of Trojan viruses, • Backdoor Trojans - This type of Trojan allows hackers to remotely access and control, a computer, often for the purpose of uploading, downloading, or executing files at, will., • Exploit Trojans -These Trojans inject a machine with code deliberately designed to, take advantage of a weakness inherent to a specific piece of software., • Rootkit Trojans -These Trojans are intended to prevent the discovery of malware, already infecting a system so that it can affect maximum damage., • Banker Trojans -This type of Trojan specifically targets personal information used for, banking and other online transactions., • Distributed Denial of Service (DDoS) Trojans - These are programmed to execute, DDoS attacks, where a network or machine is disabled by a flood of requests, originating from many different sources., • Downloader Trojans -These are files written to download additional malware, often, including more Trojans, onto a device., Visit : python.mykvs.in for regular updates

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Network Security Concepts, Ways to prevent from Trojan Hoarse, • Never download or install software from a source you don’t, trust completely, • Never open an attachment or run a program sent in an, email from someone you don’t know., • Keep all software on your computer up to date with the, latest patches, • Make sure a Trojan antivirus is installed and running on, compute, Visit : python.mykvs.in for regular updates

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Network Security Concepts, Spam - is any kind of unwanted, unsolicited digital, communication that gets sent out in bulk through, email, Ways to prevent from spam, • Never give out or post your email address publicly, • Think before click, • Do not reply to spam messages, • Download spam filtering tools and use anti-virus, software, Visit : python.mykvs.in for regular updates

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Network Security Concepts, Cookies - are files that contain small pieces of data — like a, username and password — that are exchanged between a, user's computer and a web server to identify specific users, and improve their browsing experience., Shopping sites use cookies to track items users previously, viewed, allowing the sites to suggest other goods they might, like ., Cookies can’t infect computers with viruses or other malware,, although some cyber attacks can hijack cookies and,, therefore, browsing sessions., Beware Third-Party Cookies-Third-party cookies let advertisers, or analytics companies track an individual's browsing history, across the web on any sites that contain their ads. cookies, themselves aren't harmful., Visit : python.mykvs.in for regular updates

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Network Security Concepts, Protection using firewall-, , Firewalls are software programs or hardware devices that filter and examine the, information coming through your Internet connection., All messages entering or leaving the intranet pass through the firewall, which, examines each message and blocks those that do not meet the specified security, criteria., You need a firewall to protect your confidential information from those not, authorised to access it and to protect against malicious users and accidents that, originate outside your network., One of the most important elements of a firewall is its access control features,, which distinguish between good and bad traffic., There are various types of firewall. In ascending order, they are, • Packet layer : This analyses network traffic at the transport protocol layer., • Circuit level : This validates that packets are either connection or data packets., • Application layer : This ensures valid data at the application level before, connecting., • Proxy server : This intercepts all messages entering or leaving the network., Visit : python.mykvs.in for regular updates

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Network Security Concepts, What Kind of Attacks Do Firewalls Protect Against?, Firewalls prevent cybercriminals from gaining access to your personal information., The issues include, but are not limited to:, Backdoor Access: A backdoor refers to any security holes or bugs that, when, exploited, allow unauthorized control over the program. Even entire operating, systems like Windows can have backdoors, and an experienced hacker knows how, to take advantage of them., Remote Login Hijacking: A remote desktop allows you to connect and control your, computer from another location over the internet. However, hackers can hijack the, login, access your machine, and steal your files., Email Abuse: This type of attack targets an individual in which the perpetrator sends, thousands of emails to clog the victim’s inbox. Spam email is also popular and while, most is merely annoying, some may contain viruses and malware., Source Routing: When data packets are traveling through an online network, they, are typically “passed along” by multiple routers before reaching its destination., Some hackers take advantage of this system by making malicious data packs look, like they’re coming from a trusted source. Many firewalls disable source routing for, this reason., Visit : python.mykvs.in for regular updates

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Network Security Concepts, HTTPS(Hyper text transfer protocol secure) - helps prevent intruders, from tampering with the communications between your websites and, your users' browsers. It scramble the messages using that "code" so, that no one in between can read the message. It keeps our, information safe from hackers., Https uses the "code" on a Secure Sockets Layer (SSL), sometimes, called Transport Layer Security (TLS) to send the information back, and forth., Essentially, we need three things to encrypt data:, • The data to be sent/encrypted, • A unique encryption key, • An encryption algorithm (a math function that garbles the data), asymmetric encryption is used in https. Asymmetric means we are, using two different keys, one to encrypt and one to decrypt., This encryption is now done at TLS rather than SSL., Visit : python.mykvs.in for regular updates

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Network Security Concepts, Cyber Crime - Any crime that involves a computer and a network is, called a “Computer Crime” or “Cyber Crime., Or in other term ,it is a crime in which a computer is the object of, the crime (hacking, phishing, spamming) or is used as a tool to, commit an offense (child pornography, hate crimes)., STEPS TO PROTECT YOURSELF AGAINST CYBER CRIME, , 1. Make sure your security software is current – and update it, regularly., 2. Lock or log off your computer when you step away., 3. Go offline when you don’t need an internet connection., 4. Consider sharing less online., 5. Think twice about using public Wi-Fi., 6. When in doubt, don’t click., Visit : python.mykvs.in for regular updates

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Network Security Concepts, Phishing is a cyber attack that uses disguised email as a, weapon.The attackers masquerade as a trusted entity of some kind,, The goal is to trick the email recipient into believing that the, message is something they want or need — recipient fills/send, sensitive information like account no, username ,password etc., ,then attacker use these., How to prevent phishing, • Always check the spelling of the URLs before click, • Watch out for URL redirects, that sent to a different website with identical, design, • If receive an email from that seems suspicious, contact that source with a, new email, rather than just hitting reply, • Don't post personal data, like your birthday, vacation plans, or your address, or phone number, publicly on social media, Visit : python.mykvs.in for regular updates

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Network Security Concepts, Illegal downloading is obtaining files or computer resources that w, do not have the right to use from the Internet. Copyright laws, prohibit Internet users from obtaining copies of media that we do, not legally purchase. These laws exist to prevent digital piracy,, much of which is generally conducted through Internet file sharing., How to prevent illegal downloading, movie piracy has actually decreased significantly through BitTorrent, and other traceable methods, as the adoption curve of Netflix (and, other) streaming options has increased. The answer there is simple, - make it cheaper and easier to access media in a "legal" manner,, and more people will utilize those paths than the "illegal" paths, Visit : python.mykvs.in for regular updates

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Network Security Concepts, Child pornography is considered to be any depiction of a minor or, an individual who appears to be a minor who is engaged in sexual, or sexually related conduct. This includes pictures, videos, and, computer-generated content. Even altering an image or video so, that it appears to be a minor can be considered child pornography., Child pornography is a crime in India. IT Act, 2000 & Indian Penal, Code, 1860 provides protection from child pornography.The newly, passed Information Technology Bill is set to make it illegal to not, only create and transmit child pornography in any electronic form,, but even to browse it., Visit : python.mykvs.in for regular updates

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Network Security Concepts, With the growth in online services and internet use, there are many, opportunities for criminals to commit scams and fraud. These are, dishonest schemes that seek to take advantage of unsuspecting people, to gain a benefit (such as money, or access to personal details). These, are often contained in spam and phishing messages., Common types of online scams include:, • Unexpected prize scams,, • Unexpected money scams,, • Dating or romance scams,, • Threats and extortion scams,, • Jobs and investment scams, and, • Identity theft., Do not respond to online scams or fraud. If you receive an email or SMS which looks, like a scam, the best thing to do is delete it.It is the best solution for online scam., Visit : python.mykvs.in for regular updates

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Network Security Concepts, Cyber forensics is a way or an electronic discovery technique which, is used to determine and reveal technical criminal evidence. Various, capabilities of cyber forensics are., • Computer forensics, • Computer exams., • Data analysis., • Database study., • Malware analysis., • Mobile devices., • Network analysis., • Photography., • Video analysis., Visit : python.mykvs.in for regular updates

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Network Security Concepts, Intellectual Property (IP) – is a property created by a person or group of, persons using their own intellect for ultimate use in commerce and which, is already not available in the public domain., Examples of IP Property which are, an invention relating to a product or, any process, a new design, a literary or artistic work and a trademark (a, word, a symbol and / or a logo, etc.),, , Intellectual Property Right (IPR) is the statutory right granted by the, Government, to the owner(s) of the intellectual property or applicant(s) of, an intellectual property (IP) to exclude others from exploiting the IP, commercially for a given period of time, in lieu of the discloser of his/her, IP in an IPR application., Visit : python.mykvs.in for regular updates

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Network Security Concepts, Why should an IP be protected?,  IP is an assets and can be exploited by the owner for, commercial gains any manner,  IP owner may intend to stop others from manufacturing and, selling products and services which are dully protected by him,  IP owner can sell and/or license the IP for commercial gains,  IP can be used to establish the goodwill and brand value in the, market.,  IP can be mention in resumes of it’s creator and thus show, competence of it’s creator,  IPR certificate establishes legal and valid ownership about an, intellectual property, Visit : python.mykvs.in for regular updates

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Network Security Concepts, Kinds of IPRs, • Patent (to protect technologies - The Patent Act), • Trade Mark (to protect words, signs, logos, labels –The Trade, Mark Act), • Design (to protect outer ornamental configuration –The, Designs Act), • Geographical Indications (GI) (to protect region specific, product –The Geographical Indications of Goods Act), • Copyright (to protect literary and artistic work –The Copyright, Act), , Visit : python.mykvs.in for regular updates

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Network Security Concepts, IPRs are protected in accordance with the provisions of, legislations of a country specific. In India, IPRs can be protected, and monopolized as per the act. Some of them are, 1- The Patent Act, 1970,, 2- The Designs Act, 2000,, 3- The Trade Mark Act, 1999,, 4- The Geographical Indications of Goods Act, 1999,, 5- The Copyright Act, 1957,, 6- Protection of Integrated Circuits Layout and Designs Act, 2000,, 7- Protection of Plant Varieties and Farmers Rights Act, 2001, and, also Trade Secret, Visit : python.mykvs.in for regular updates

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Network Security Concepts, Hacking is identifying weakness in computer systems or networks to exploit its weaknesses, to gain access. Example:Using password cracking algo. to gain access to a system., Types of hackers • Ethical Hacker (White hat): A hacker who gains access to systems with a view to fix the, identified weaknesses. They may also perform penetration Testing and vulnerability, assessments., • Cracker (Black hat): A hacker who gains unauthorized access to computer systems for, personal gain. The intent is usually to steal corporate data, violate privacy rights, transfer, funds from bank accounts etc., • Grey hat: A hacker who is in between ethical and black hat hackers. He/she breaks into, computer systems without authority with a view to identify weaknesses and reveal them to, the system owner., • Script kiddies: A non-skilled person who gains access to computer systems using already, made tools., • Hacktivist: A hacker who use hacking to send social, religious, and political, etc. messages., This is usually done by hijacking websites and leaving the message on the hijacked website., • Phreaker:A hacker who identifies and exploits weaknesses in telephones instead of, computers., Visit : python.mykvs.in for regular updates

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Network Security Concepts, Cyber law is any law that applies to the internet and internet-related, technologies. Cyber law provides legal protections to people using the, internet. This includes both businesses and everyday citizens., Understanding cyber law is of the utmost importance to anyone who, uses the internet. Cyber law is important because it touches almost all, aspects of transactions and activities and on involving the internet,, World Wide Web and cyberspace. Every action and reaction in, cyberspace has some legal and cyber legal angles., Cyber Laws in India prevent any crime done using technology, where a, computer is a tool for cybercrime. IT Act 2000 was enacted and, amended in 2008 covering different types of crimes under cyber law in, India., Visit : python.mykvs.in for regular updates

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Network Security Concepts, The Information Technology Act, 2000 provides legal recognition to the transaction, done via an electronic exchange of data and other electronic means of, communication or electronic commerce transactions.Some of sections under it act, 2000 are given below., SECTIO, N, , OFFENCE, , PENALTY, , 67A, , Publishing images containing sexual, acts, , Imprisonment up to seven years, or/and with fine up to Rs., 1,000,000, Imprisonment up to five years, or/and with fine up, to Rs.1,000,000 on first conviction. Imprisonment up to, seven years, or/and with fine up to Rs.1,000,000 on second, conviction., , 67B, , Publishing child porn or predating, children online, , 67C, , Failure to maintain records, , Imprisonment up to three years, or/and with fine., , 68, , Failure/refusal to comply with orders, , Imprisonment up to three years, or/and with fine up, to Rs.200,000, , 69, , Failure/refusal to decrypt data, , Imprisonment up to seven years and possible fine., , 70, , Securing access or attempting to, secure access to a protected system, , Imprisonment up to ten years, or/and with fine., , 71, , Misrepresentation, , Imprisonment up to three years, or/and with fine up, to Rs.100,000, , Visit : python.mykvs.in for regular updates