70218 - Telecommunications Networks

Learning outcomes

The student will learn how the Internet works, with particular reference to addressing and routing of information.

Course contents

1. Internet architecture. The IP protocol. Addressing, subnetting and supernetting, CIDR. Direct and indirect forwarding.
   
2. Signaling and management in IP networks: ICMP, DHCP, NAT, ARP.
3. Routing in the Internet. Distance vector versus link state protocols. Authonomous Systems. Interior (IGP) and Exterior (EGP) routing protocols. Configuring RIP and OSPF.
4. Network Overlays: GRE, VLAN, VxLAN etc.
5. Introduction to network security. VPNs.
6. Local Area Networks (LANs). The Ethernet LAN and IEEE 802.3. Wireless LANs and IEEE 802.11.

Readings/Bibliography

J. F. Kurose, K. W. Ross, Computer Networking: A Top-Down Approach, Global Edition, Pearson Education; 8th edition (2021)

Teaching methods

Lectures

Practical experiments:

• network traffic analysis (Wireshark);
• IP network configuration
• analysis of forwarding and routing

Assessment methods

The exam is conducted in the computer laboratory using the Esami on Line platform.

Exam Format

The exam consists of a test that includes multiple-choice questions, open-ended questions, and exercises.

In the case of open-ended questions (essays), students are required to answer one or more questions related to the course topics using their own words. Questions are usually structured into sub-points, and answers should follow the same structure.

For exercises, similar to those presented during the classes, students are asked to solve one or more numerical problems, or to perform operations related to protocol functioning or device configuration.

For multiple-choice questions, students must answer a series of pre-formatted questions, either graphical or textual. Text-based questions consist of a statement followed by three possible answers or statements, and can be of two types:

• Multiple choice - multiple answer questions, where students are asked to identify which of the three statements are true. More than one (or all) statements may be true, but at least one always is.

• Mutually exclusive multiple-choice questions, where students must identify the single true statement among the three proposed (if one is true, the others are consequently false).

Exam Composition

Typically, each exam includes 20 questions, one of which is open-ended.
In addition, one optional question/exercise related to the practical sessions is proposed; it is not mandatory and may be completed at the student’s discretion.

Evaluation

The open-ended question is graded manually by the examination board and is worth up to 10 points.
Multiple-choice questions and exercises are graded automatically, with a maximum total score of 23 points.

Multiple-choice evaluation

• Non-mutually exclusive multiple-choice:
  The score depends on which statements the student selects as true.

  • If all and only the true statements are selected → 1 point.

  • If only some of the true statements are selected → a proportional fraction of 1 point (e.g., if all three statements are true but only one is selected → 1/3 point).

  • If false statements are also selected as true → a negative score is assigned, adjusted so that selecting all statements as true yields 0 points.

  • The minimum score per question is 0 (never negative).

• Mutually exclusive multiple-choice:

  • Correct answer (true statement selected) → 1 point.

  • Incorrect answer (false statement selected) → 0 points.

The optional practical exercise, if completed, is graded on a scale from 0 to 3 points.

Final Grade and Conversion to a 30-Point Scale

The final score is calculated as follows:

• D: theoretical section score, up to 33 points (0 ≤ D ≤ 33)

• P: practical section score, up to 3 points (0 ≤ P ≤ 3)

The final grade V (out of 30) is computed by rounding to the nearest integer using the formula:
V = (D / 33) × 30 + P

Honors (lode) are typically awarded to students who achieve a score above 30.
The practical section score P may be 0 without preventing the student from passing the exam.

Duration

The exam lasts 1 hour and 45 minutes (105 minutes).

Recording of Results

All exam results are officially recorded within 5 days after their publication. Four outcomes are possible:

1. Pass — grade between 18 and 30, possibly with honors.

2. WITHDRAWN — if the student does not attend or decides to withdraw during the exam; in this case, the test is not graded.

3. FAILED — if the exam score is insufficient to pass.

4. REJECTED — if the grade is sufficient, but the student chooses not to accept it and wishes to retake the exam.

After the results are published, the instructor sends an email to all students who took the exam, indicating the date of official recording. Students who passed may reject their grade by replying to this email and explicitly stating their decision.

Retaking the Exam

Students who withdrew, failed, or rejected their grade may freely retake the exam during any subsequent scheduled session.

Rules of Conduct

Students must present their student ID (or another photo ID) — failure to do so will result in exclusion from the exam session.

The following are strictly prohibited:

• Consulting books, notes, or other materials of any kind. Bags and backpacks must be left at the entrance.

• Connecting external storage devices to the computer or accessing files stored on the hard drive.

• Using any applications other than the browser and calculator, or opening any browser page other than the exam page.

Violation of these rules will result in immediate removal from the exam and the assignment of a “FAILED” result.

Teaching tools

Lecture notes and slides (in Italian) available on the Virtuale platform.

Office hours

See the website of Franco Callegati

See the website of Andrea Piroddi