MCA-126 Information Security Notes from Unnati Educations cover all 4 units of this GGSIPU MCA Semester 2 Core Elective I paper in 76 pages, with 49 solved short-answer questions, 33 long-answer practice questions, 4 worked numericals and 22 figures. They follow the MCA syllabus effective from Academic Year 2025-26.
Written by Prateek Talwar, Founder, Unnati Educations · Reviewed by Ritik Rawat, B.Tech, Senior Full Stack Developer · Checked against the official MCA scheme (effective 2025-26) · Updated 13 October 2026 · Editorial policy
Scheme: MCA (2 years), affiliated institutes, effective 2025-26 | Applies to: Academic Year 2025-26 onwards | Verified against: MCA Scheme of Examination and Detailed Syllabus, 13 Oct 2026
MCA-126 Information Security at a glance: GGSIPU MCA Sem 2 credits, units and exam pattern
| Code and title | MCA-126 Information Security |
|---|---|
| Course and semester | MCA (2 years), Semester 2 |
| Category and credits | Core Elective I (one of ten options) · L 3, T 1 · 4 credits |
| Marks | Out of 100; pass marks 40. Internal and end-term split not printed in the official PDF |
| End-term pattern | Q1 compulsory, short answers on the whole syllabus, 12 marks; then one of two questions per unit, 12 marks each (12 + 48 = 60 marks) |
| Paired lab | MCA-168 Information Security Lab · 0-2 · 1 credit |
Verify these facts in the official MCA syllabus PDF on ipu.ac.in: pass marks in Important Note 9 (page 8), the MCA-126 paper pattern on page 65 and the unit topics on page 66.
If fewer than 20 students pick this elective, you complete it on SWAYAM with approval. Full paper list: GGSIPU MCA Semester 2 papers.
Re-appear rules sit in Ordinance 11 on ipu.ac.in. These GGSIPU MCA Sem 2 Information Security notes follow the same four-unit split the paper setter uses.
MCA-126 Information Security Notes unit-wise: 49 solved short answers, 4 worked numericals and 22 figures across 4 units
These MCA-126 Information Security IPU notes run 76 pages, and each unit ends with a Quick Revision Table, solved short answers and long-answer practice. Every other paper is listed under GGSIPU MCA notes.
The official PDF numbers units without titles, so the names below are the notes' own. Pages 8, 31, 46 and 72 are in the sample PDF above.
MCA-126 Unit 1: Introduction to Information Security, Security Threats and Ethical Issues
Pages 5-21, 15 sections. CIA plus accuracy and authenticity, with Indian cases like IRCTC Tatkal booking, and the 27-cell McCumber Cube. Then Whitman and Mattord's 12 threat categories, 14 common attacks, control types and the SecSDLC, then law vs ethics with IT Act 2000 sections and six codes of ethics. 12 solved short answers, 8 long-answer practice questions, 4 figures.
| Basis | Passive | Active |
|---|---|---|
| Attacker | Observes | Modifies or disrupts |
| Hits | Confidentiality | Integrity, availability |
| Detection | Hard | Easier |
| Examples | Sniffing, traffic analysis | Replay, masquerade, DoS |
Quick look: passive vs active attacks (from page 12)
- Basis
- Attacker
- Passive
- Observes
- Active
- Modifies or disrupts
- Basis
- Hits
- Passive
- Confidentiality
- Active
- Integrity, availability
- Basis
- Detection
- Passive
- Hard
- Active
- Easier
- Basis
- Examples
- Passive
- Sniffing, traffic analysis
- Active
- Replay, masquerade, DoS
MCA-126 Unit 2: Managing IT Risk and Security Plan
Pages 22-38, 13 sections. Weighted factor analysis, the TVA worksheet and the risk formula lead into five control strategies (D-T-M-A-T) and quantitative vs qualitative analysis. Planning covers governance, EISP, ISSP and SysSP, ISO 27000 with PDCA, NIST CSF 2.0 and SETA. 12 solved short answers, 8 long-answer practice questions, 3 worked numericals, 6 figures.
Quick look: is DDoS protection worth ₹2,00,000 a year? (from page 28)
- SLE = ₹10,00,000 × 0.4 = ₹4,00,000
- ALE (prior) = 4,00,000 × 2 = ₹8,00,000
- ALE (post) = 4,00,000 × 0.25 = ₹1,00,000
- CBA = 8,00,000 − 1,00,000 − 2,00,000 = ₹5,00,000, positive, so the control is justified
MCA-126 Unit 3: Security Technologies: Access Control, Firewalls, IDPS and Biometrics
Pages 39-58, 23 sections, the longest unit. IAAA and access models from DAC to ABAC, five firewall processing modes by OSI layer, RADIUS, Kerberos, SESAME and VPN modes, then IDPS detection methods, honeypots, OS hardening, tools like nmap, and biometric FAR, FRR and CER. 13 solved short answers, 9 long-answer practice questions, 7 figures.
| Basis | NIDPS | HIDPS |
|---|---|---|
| Watches | Network packets | Logs, files, processes |
| Encrypted traffic | Cannot inspect | Can inspect |
| Attack success known? | Usually not | Yes |
| Example | Snort | OSSEC |
Quick look: NIDPS vs HIDPS (from pages 51-52)
- Basis
- Watches
- NIDPS
- Network packets
- HIDPS
- Logs, files, processes
- Basis
- Encrypted traffic
- NIDPS
- Cannot inspect
- HIDPS
- Can inspect
- Basis
- Attack success known?
- NIDPS
- Usually not
- HIDPS
- Yes
- Basis
- Example
- NIDPS
- Snort
- HIDPS
- OSSEC
MCA-126 Unit 4: Implementing Information Security, Maintenance and Digital Forensics
Pages 59-76, 16 sections. BYOD controls, a 7-task sample WBS with PERT, four conversion strategies and certifications from CISSP to OSCP, then the five-domain maintenance model, six types of vulnerability assessment and the forensics process with Section 63 of the Bharatiya Sakshya Adhiniyam 2023. 12 solved short answers, 8 long-answer practice questions, 1 worked numerical, 5 figures.
| Score | Severity | Fix within |
|---|---|---|
| 9.0-10.0 | Critical | 24-72 hours |
| 7.0-8.9 | High | A week |
| 4.0-6.9 | Medium | A month |
| 0.1-3.9 | Low | Routine maintenance |
Quick look: CVSS v3 severity (from page 69)
- Score
- 9.0-10.0
- Severity
- Critical
- Fix within
- 24-72 hours
- Score
- 7.0-8.9
- Severity
- High
- Fix within
- A week
- Score
- 4.0-6.9
- Severity
- Medium
- Fix within
- A month
- Score
- 0.1-3.9
- Severity
- Low
- Fix within
- Routine maintenance
Screened subnet DMZ and firewall rule sets in information security: excerpt from page 46 of the MCA-126 notes
Excerpt from page 46
Dual-homed host architecture
The bastion host has two network interface cards: one faces the external network and one faces the internal network. All traffic has to pass through it, and IP forwarding is switched off. It often performs NAT, which hides internal addresses. The weakness is simple: if this one host is compromised, the inside network is exposed.
Screened subnet architecture (with DMZ)
This is the most widely used design today. One or more bastion hosts sit between two filtering routers or firewalls, which creates an isolated network called the DMZ (demilitarised zone). Public servers such as web, mail and DNS live in the DMZ.
- Connections from outside are allowed only into the DMZ.
- Connections from the DMZ to the internal network are tightly restricted.
- If a DMZ server is hacked, the second firewall still protects the internal LAN.
- A part of the DMZ used to give partners access to some internal data is called an extranet.
Selecting the right architecture
Four questions decide the choice: what protection the organisation needs, how much budget is available for purchase, staff and maintenance, how the firewall fits the existing network, and what skills are needed to configure and maintain it.
Configuring and managing firewalls
A firewall is only as good as its rule set. Rules are read from top to bottom, the first matching rule is applied, and the last rule should be a deny-all cleanup rule.
Whitman and Mattord's best practices include: never make the firewall directly reachable from the public network, route SMTP only to a mail gateway, deny ICMP from outside to stop network mapping, block Telnet in favour of SSH or VPN, allow HTTP and HTTPS only to a web server in the DMZ, and deny anything not verified as authentic.
| # | Source | Destination | Service | Action |
|---|---|---|---|---|
| 1 | Any | Firewall itself | Any | Deny |
| 2 | Internal 10.10.0.0/16 | Any | Any | Allow |
| 3 | Any | DMZ web 10.10.10.5 | TCP 80, 443 | Allow |
| 4 | Any | DMZ mail 10.10.10.6 | TCP 25 | Allow |
| 5 | Any | Internal | ICMP | Deny |
| 6 | Any | Internal | TCP 23 (Telnet) | Deny |
| 7 | Any | Any | Any | Deny (cleanup) |
Sample firewall rule set (excerpt, page 46)
- #
- 1
- Source
- Any
- Destination
- Firewall itself
- Service
- Any
- Action
- Deny
- #
- 2
- Source
- Internal 10.10.0.0/16
- Destination
- Any
- Service
- Any
- Action
- Allow
- #
- 3
- Source
- Any
- Destination
- DMZ web 10.10.10.5
- Service
- TCP 80, 443
- Action
- Allow
- #
- 4
- Source
- Any
- Destination
- DMZ mail 10.10.10.6
- Service
- TCP 25
- Action
- Allow
- #
- 5
- Source
- Any
- Destination
- Internal
- Service
- ICMP
- Action
- Deny
- #
- 6
- Source
- Any
- Destination
- Internal
- Service
- TCP 23 (Telnet)
- Action
- Deny
- #
- 7
- Source
- Any
- Destination
- Any
- Service
- Any
- Action
- Deny (cleanup)
Do the MCA-126 notes cover the full GGSIPU syllabus?
Yes. Every topic printed under the four official units has a section in the notes. Malware (viruses, worms, Trojans), named in the learning objectives, sits inside "Common Attacks" on page 12, not in a chapter of its own.
| Unit | Official topics | In the notes | Status |
|---|---|---|---|
| I | Introduction to Information Security; Security Threats, Secure Software Development; Ethical Issues, Codes of Ethics | Sections 1-15, pages 6-18 | Covered |
| II | Managing IT Risk, Quantitative and Qualitative Risk Control; Security Plan, ISO, NIST Models, SETA | Sections 1-13, pages 23-35 | Covered |
| III | Access Control; Firewalls; Intrusion Detection and Prevention System, Security Tools, Biometrics | Sections 1-23, pages 40-55 | Covered |
| IV | Remote Computing, Security Project Management, Certifications; Maintenance Models, Vulnerability Assessment, Digital Forensics | Sections 1-16, pages 60-73 | Covered |
MCA-126 official topics vs the notes
- Unit
- I
- Official topics
- Introduction to Information Security; Security Threats, Secure Software Development; Ethical Issues, Codes of Ethics
- In the notes
- Sections 1-15, pages 6-18
- Status
- Covered
- Unit
- II
- Official topics
- Managing IT Risk, Quantitative and Qualitative Risk Control; Security Plan, ISO, NIST Models, SETA
- In the notes
- Sections 1-13, pages 23-35
- Status
- Covered
- Unit
- III
- Official topics
- Access Control; Firewalls; Intrusion Detection and Prevention System, Security Tools, Biometrics
- In the notes
- Sections 1-23, pages 40-55
- Status
- Covered
- Unit
- IV
- Official topics
- Remote Computing, Security Project Management, Certifications; Maintenance Models, Vulnerability Assessment, Digital Forensics
- In the notes
- Sections 1-16, pages 60-73
- Status
- Covered
Official source: MCA Scheme of Examination and Detailed Syllabus, effective 2025-26 (ipu.ac.in)
For CO3 (security audits on databases and networks), read the Unit 2 TVA worksheet with the Unit 4 intranet assessment. Every course in GGSIPU notes is mapped to its official PDF this way.
How to write MCA-126 answers: definition-first theory answers and SLE, ALE and PERT numericals
The notes give one flow for every theory answer: definition, diagram, explanation in points, example, then a one-line conclusion. For the definition of InfoSec, Unit 1 prints three standard versions (CNSS, ISO/IEC 27000 and NIST) and asks you to write any one word for word.
- Diagrams carry this paper. Of the 22 figures, practise these until each takes two minutes: the CIA triad, the threat-vulnerability-attack chain, the policy hierarchy, the five risk control strategies, the four firewall architectures, NIDPS vs HIDPS placement and the FAR/FRR curve with CER where they cross.
- Close pairs as tables. The common mistake is blurring close pairs. Answer them as a two-column table with at least five rows of basis, meaning and example: accuracy vs integrity, threat vs vulnerability, IDS vs IPS, RADIUS vs TACACS+, certification vs accreditation, VA vs penetration testing.
- Marks labels. The notes tag short answers "2.5 Marks" and long answers "12.5 Marks", but the 2025-26 paper-setter instructions give Question 1 twelve marks in total and each unit question 12 marks. Plan a long answer as about two pages with one diagram and one table.
- Indian law points. Add them where they fit, like IT Act Section 66 for hacking or Section 65B for electronic evidence, and close Unit 4 forensics answers with the chain of custody, since the notes give a filled custody record on page 72 you can copy as a model.
Worked example: PERT expected time (page 63)
Numericals follow a fixed order: formula, each step, then a conclusion line.
O = 2 days, M = 4 days, P = 12 days
TE = (O + 4M + P) / 6
TE = (2 + 16 + 12) / 6 = 5 days
Conclusion: expected time is 5 days.Practise this format on GGSIPU MCA important questions.
MCA-126 exam corner: 49 solved short answers and 33 long-answer practice questions by unit
| Unit | Short, solved (2.5 Marks) | Long, practice (12.5 Marks) | Worked numericals |
|---|---|---|---|
| 1 | 12 | 8 | 0 |
| 2 | 12 | 8 | 3 |
| 3 | 13 | 9 | 0 |
| 4 | 12 | 8 | 1 |
MCA-126 questions in the notes, by unit (labels as printed)
- Unit
- 1
- Short, solved (2.5 Marks)
- 12
- Long, practice (12.5 Marks)
- 8
- Worked numericals
- 0
- Unit
- 2
- Short, solved (2.5 Marks)
- 12
- Long, practice (12.5 Marks)
- 8
- Worked numericals
- 3
- Unit
- 3
- Short, solved (2.5 Marks)
- 13
- Long, practice (12.5 Marks)
- 9
- Worked numericals
- 0
- Unit
- 4
- Short, solved (2.5 Marks)
- 12
- Long, practice (12.5 Marks)
- 8
- Worked numericals
- 1
The MCA-126 notes solve 49 short-answer questions across 4 units, plus 4 worked numericals, and add 33 long-answer practice questions.
- Differentiate accuracy and integrity (Unit 1). Pointer: accuracy: data was correct when created. Integrity: it was not altered afterwards (page 19).
- When is the "accept" strategy appropriate? (Unit 2) Pointer: only after the risk is assessed and a cost-benefit analysis shows protection costs more than the expected loss (page 36).
- Differentiate RADIUS and TACACS+ (Unit 3). Pointer: RADIUS: UDP, encrypts only the password. TACACS+: TCP, separates the AAA functions, encrypts the whole packet body (page 57).
- Why use write blockers and hash values? (Unit 4) Pointer: write blockers stop changes to original evidence; matching SHA-256 hashes prove the image is exact (page 75).
More practice sits in the MCA-126 important questions.
Who writes and checks the MCA-126 InfoSec notes?
- Prateek Talwar, author: Founder, Unnati Educations; Associate Company Secretary (ACS), ICSI, membership no. 58704, since 15 May 2019; B.Com, University of Delhi (School of Open Learning), 2012. Profile
- Ritik Rawat, subject reviewer: Senior Full Stack Developer, Unnati Educations; B.Tech.
Built on TB1, Whitman and Mattord's Principles of Information Security. The 2026-27 edition adds what the 2003 text book predates: the DPDP Act 2023, ISO/IEC 27002:2022 and NIST CSF 2.0. Last updated 13 October 2026. See our editorial policy.
The same team prepares GGSIPU important questions for every course.
MCA-126 and the MCA-168 Information Security lab (1 credit), plus other GGSIPU MCA Sem 2 papers
Paired lab: MCA-168 Information Security lab notes. The official PDF prints six outcomes but no practical list. Prerequisite: basic MATLAB.
Lab outcomes draw on:
- Unit 2 risk (pages 23-29).
- Unit 3 OS hardening (pages 52-53).
- Unit 1 attacks (pages 10-12).
- Unit 3 IAAA (pages 40-42).
The PKI outcome goes beyond these notes.
Same semester: MCA-102 Data and File Structures, MCA-104 Object Oriented Software Engineering, MCA-106 Python Programming, one Open Elective I (MCA-128 to MCA-134), MCA-170 Minor Project II, MCA-172 and MCA-174. The SecSDLC in Unit 1 lines up with MCA-104, and MCA-221 Applied Cryptography in Semester 3 builds on this paper.
MCA-126 InfoSec notes FAQs
How do I get the full MCA-126 notes?
Tap "Get Full Notes" on this page to message our desk on WhatsApp at 9899436384. The full MCA-126 notes come only as a printed book, not as a PDF, covering all 4 units in 76 pages. Delivery takes 5 to 7 days at most, depending on your location, and the team shares the order details on WhatsApp.
Is MCA-126 compulsory in GGSIPU MCA Semester 2?
No. MCA-126 is one of ten Core Elective I options, and you choose one, for example MCA-108 Advanced DBMS or MCA-116 Web Technologies instead. Each option carries 4 credits (L 3, T 1). If fewer than 20 students choose an elective, the scheme lets you complete it on SWAYAM with prior approval, while your institute still evaluates you.
What is the passing mark for MCA-126 Information Security?
MCA-126 is marked out of 100; the official PDF does not print the internal and end-term split, and its paper-setter pattern totals 60 marks (12 + 48). The MCA scheme of examination states pass marks as 40%, which is 40 out of 100, for every paper. End-term minimums and re-appear rules are in Ordinance 11.
Which MCA-126 unit is the biggest in the notes?
Unit 3: 20 pages and 23 sections on access control, firewalls, remote connections, IDPS, security tools and biometrics. It also has the most questions, 13 solved short answers and 9 long-answer practice questions, plus 7 of the 22 figures. Units 1 and 2 run 17 pages each and Unit 4 runs 18, so give Unit 3 extra revision time.
Do the MCA-126 notes include solved numericals?
Yes, four. Unit 2 works the Whitman and Mattord risk formula to a score of 35, solves a full SLE, ALE and cost-benefit case for DDoS protection, and gives an answer key for a practice numerical on a ₹5,00,000 asset. Unit 4 solves a PERT expected-time example. Each shows the formula, every step and a conclusion line.
Which text book do the MCA-126 notes follow?
TB1 of the official syllabus, Whitman and Mattord's Principles of Information Security, for the 12 threat categories, risk formula, policy types, firewall best practices, biometric rankings and the maintenance model. Indian material is added on top: IT Act 2000 sections, the DPDP Act 2023, CERT-In, and Section 63 of the Bharatiya Sakshya Adhiniyam 2023 for electronic evidence.
Get the full MCA-126 Information Security Notes on WhatsApp
The full notes come only as a printed book, not as a PDF. These are Information Security notes in English. Delivery: within 5 to 7 days at most; the exact time may vary with your location.
Order the MCA-126 Information Security Notes book on WhatsApp (4 units, 76 pages)
Unnati Educations is an independent education provider based in Vikaspuri, Delhi. We are not affiliated with, authorised by, or endorsed by Guru Gobind Singh Indraprastha University (GGSIPU). 'GGSIPU' and 'IPU' are used only to describe the syllabus our notes follow. For official information, visit ipu.ac.in.
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