1.1 Introduction to Cyber Security★

# A Day Full of Targets

• You pay by UPI, check results online and chat on WhatsApp, all before lunch.
• Each of those steps can be spied on, changed or blocked by a stranger.
• In 2018, hackers took about ₹94 crore from a Pune bank within days.
• Who protects all this, and how? That is cyber security.

# Cyber Security PYQ 1M · other

Cyber security is the practice of protecting computers, networks, programs and data from attacks, damage and unauthorised access.

Cyber security, information security and network security

• Information security: protects information in every form, paper or digital, through the CIA triad (→ 1.3).
• Cyber security: protects digital systems and data from attacks that come through cyberspace (→ 1.2).
• Network security: the part of cyber security that protects the network itself: traffic, devices and connections.
• Information security is the widest of the three; network security is the narrowest.

Why it matters

1. Daily life runs online: UPI payments, Aadhaar services, DigiLocker, online exams, hospital records.
2. More users and devices: hundreds of millions of smartphone users, plus smart (IoT) devices in homes and factories.
3. Rising crime: India recorded 86,420 cybercrime cases in 2023 (NCRB).
4. Cost of a breach: stolen money, services down, fines and lost trust (→ 1.7).
5. National security: power grids, banks and defence systems can be attacked from abroad (→ 1.5).
6. Privacy: personal data, photos and chats must stay private.

Challenges

1. Threats keep changing: new malware and zero-day flaws (weaknesses the maker doesn't know about yet, so no patch exists).
2. Growing attack surface: every cloud service, phone and IoT device is one more way in.
3. Ransomware: cheap to launch, costly to recover from.
4. Insiders: employees who misuse their access or make mistakes.
5. Low user awareness: most attacks begin with a click on a fake link.
6. Skills shortage: too few trained security professionals.
7. Legacy systems: old software that can no longer be patched.
8. Cross-border crime: the attacker sits in another country, out of reach of local police.

Why today's defence may not work tomorrow

• Attackers keep updating their attack vectors, the paths and methods they use to get in.
• New vulnerabilities are found in software every day, and every new technology brings new weaknesses.
• So security is a continuous process: monitor, patch, update and train, again and again.

From Creeper to ransomware

• 1971, Creeper: an experimental program that moved between ARPANET computers, showing "I'm the creeper, catch me if you can". Reaper was written to delete it, the first antivirus.
• 1986, Brain: the first virus for IBM PCs, written in Pakistan.
• 1988, Morris worm: slowed thousands of internet computers and led to the first CERT (Computer Emergency Response Team).
• 2017, WannaCry: ransomware that hit computers in over 150 countries (→ 2.4).
• Today: organised gangs, state-backed groups and AI-driven attacks; defences move towards zero trust ("never trust, always verify") and quantum-safe encryption.

# Elements of Cyber Security PYQ 1M

Cyber security is made of several elements (domains), each protecting one part of the digital world.

1. Application security: keeping software free of exploitable flaws (→ 2.12).
2. Information (data) security: protecting data when stored and when sent.
3. Network security: firewalls, intrusion detection, secure Wi-Fi (→ 6.6).
4. Endpoint security: protecting laptops, phones and servers with antivirus, patches and device control.
5. Cloud security: protecting data and applications on cloud platforms.
6. IoT security: protecting smart devices such as CCTV cameras, smart meters and medical devices.
7. Identity and access management (IAM): who can log in, and what each person can open.
8. Operational security: day-to-day processes and decisions for handling data.
9. Disaster recovery and business continuity: getting back to work after an attack or disaster (→ 4.11).
10. End-user education: training people not to fall for tricks.

• Attacks are not a component: they are what the components defend against.

Defence in depth

• Several layers of protection, so that if one layer fails, the next still stops the attacker.
• Built from people (trained users), process (policies, incident response) and technology (firewalls, encryption).

flowchart TD
    A["<b>Attacker</b><br>(from the internet)"]:::amber --> B["<b>Perimeter</b><br>(firewall, email filter)"]:::blue
    B --> C["<b>Network</b><br>(IDS, segmentation)"]:::blue
    C --> D["<b>Endpoint</b><br>(antivirus, patches)"]:::blue
    D --> E["<b>Application</b><br>(secure code, MFA)"]:::blue
    E --> F["<b>Data</b><br>(encryption, backup)"]:::green
    classDef blue fill:#5b84d424,stroke:#5b84d480
    classDef amber fill:#d6a24424,stroke:#d6a24480
    classDef green fill:#52a86e24,stroke:#52a86e80

• Example: a phishing email slips past the spam filter and the user types in a password, but MFA stops the attacker from logging in.

# Cognitive Cybersecurity PYQ 1M · other

Cognitive cybersecurity is the use of artificial intelligence and machine learning that learn like a human analyst to detect, understand and respond to threats.

• It reads huge amounts of data (logs, alerts, threat reports, even news articles) that no human team could read in time.
• It learns what normal activity looks like and flags anything unusual, such as a login at 3 am from another country.
• It suggests or takes action quickly, so analysts can focus on the real attacks.
• Example: IBM's Watson for Cyber Security reads security research and helps analysts investigate alerts.