Description

Operating principles, architecture, technology and norms of computer networks, especially of Internet. Design-oriented course, complemented by practical skills

Requirements

Subjects that it is recommended to have taken before

• Data Communication (V05G301V01204)

Instructors

• López Ardao, José Carlos
• Rivas Costa, Carlos
• Sousa Vieira, Estrella

Contents

1. Introduction

• 1.1 Network elements, types of links, services and protocols
• 1.2 Switching techniques: circuits, messages and packets
• 1.3 Reference models and service modes

2. Packet switching (I): Link Transmission

• 2.1 Delimitation and transmission of frames
• 2.2 Multiplexing in the link: static vs. statistical
• 2.3 Forwarding techniques: generalized forwarding, virtual circuits and datagrams
• 2.4 Packet switching: delay and losses in a link

3. Packet switching (II): Route Transmission

• 3.1 Fundamental metrics: delay, losses, equivalent capacity
• 3.2 Reliable end-to-end transmission (hop-by-hop vs. end-to-end retransmissions)
• 3.3 Flow control

4. The Data Plane (I): IEEE 802.x networks

• 4.1 Link layer and link types
• 4.2 IEEE 802 project
• 4.3 Flat addressing in IEEE 802
• 4.4 IEEE 802 bridges
• 4.5 IEEE 802.3: Ethernet
• 4.6 IEEE 802.11: WiFi

5. The Data Plane (II): IP networks

• 5.1 Internet and IP
• 5.2 Hierarchical addressing and IP structure
• 5.3 Routers and forwarding tables
• 5.4 Longest prefix match
• 5.5 IP protocol: IPv4 and IPv6
• 5.6 Addressing scopes and private networks
• 5.7 NAT

6. Interconnection of Link Networks

• 6.1 IP as an interconnection network
• 6.2 Routers vs. bridges
• 6.3 Address translation: NDP / ARP
• 6.4 IP fragmentation

7. The Control Plane (I): IEEE 802.x networks

• 7.1 Data and control planes, distributed vs. centralized control
• 7.2 Control plane in IEEE 802 networks
• 7.3 Backward learning
• 7.4 Spanning Tree Protocol (STP)

8. The Control Plane (II): IP networks

• 8.1 Routing problem: algorithms, protocols, RIB
• 8.2 Hierarchical routing: autonomous systems and domains
• 8.3 RIB format and FIB generation
• 8.4 Intra-domain routing: RIP and OSPF
• 8.5 Inter-domain routing: BGP

9. The Transport Layer

• 9.1 Multiplexing, reliability and transmission modes
• 9.2 Transport protocols
• 9.3 UDP
• 9.4 TCP: connection management, ordered delivery, ARQ, flow control

10. Congestion Control

• 10.1 Congestion problem
• 10.2 Objectives, requirements and mechanisms
• 10.3 TCP congestion control: AIMD algorithm
• 10.4 Classic implementations: Tahoe, Reno
• 10.5 Delay-based mechanisms: Vegas

11. Internet Security

• 11.1 Secure communication systems
• 11.2 Confidentiality: symmetric and asymmetric cryptography
• 11.3 Authenticity and integrity: hash functions, digital signatures
• 11.4 Availability: DDoS attacks
• 11.5 Secure transport: TLS over TCP

Lab Sessions

• Practical work using network tools: GNS3, Wireshark, ping, traceroute, dig
• Reinforcement of lecture content through hands-on exercises
• Software used: GNS3, Wireshark, Java
• Introduction to programming concepts: sockets and network utilities

Learning Outcomes

B1

• CG1: The ability to write, develop and sign projects in the field of Telecommunication Engineering, including the conception, development, and operation of networks, services, and applications in Telecommunications and Electronics

B3

• CG3: Knowledge of basic subjects and technologies that enables learning new methods and adapting to new situations with versatility

B4

• CG4: Ability to solve problems with initiative, make creative decisions, and communicate knowledge and skills, understanding ethical and professional responsibility

B6

• CG6: Aptitude to manage mandatory specifications, procedures, and laws

B9

• CG9: Ability to work in multidisciplinary and multilingual environments, and to communicate knowledge, procedures, results, and ideas effectively

C11

• CE11/T6: Ability to conceive, deploy, organize, and manage telecommunication networks, systems, services, and infrastructures in various environments, considering social and economic impact

C17

• CE17/T12: Knowledge and use of communication network architecture, protocols, and interfaces

C18

• CE18/T13: Ability to differentiate access vs. transport networks, packet vs. circuit switching, mobile vs. fixed networks, and multimedia services

C19

• CE19/T14: Knowledge of networking and routing methods, and fundamentals of planning and evaluating networks based on traffic parameters

D2

• CT2: Understanding engineering within a sustainable development framework

D3

• CT3: Awareness of lifelong learning and continuous improvement, with an ethical and inclusive attitude

D4

• CT4: Promotion of teamwork and skills in communication, organization, planning, and responsibility in multilingual and multidisciplinary environments

Recommended Readings and Tools

To take the course, in order to carry out the network programs, it is very important to have a certain programming skills in an object-oriented language such as Java (or C ++). The skill level obtained after passing the Programming II course is enough.

Planned Activities

Lecturing

• Exposition of ideas, concepts, techniques, and algorithms related to the course topics
• Competences developed: D2, D3, B3, B4, C11, C17, C18, C19

Problem solving

• Resolution of problems and exercises in class by the professor based on lecture content
• Competences developed: B3, B4, C11, C17, C18, C19

Laboratory practical

• Networking laboratory sessions using tools such as GNS3, Wireshark, ping, traceroute, dig
• Reinforcement of lecture content through hands-on practice
• Software used: GNS3, Wireshark, Java
• Competences developed: B1, B9, C17, C19

Autonomous problem solving

• Weekly online activities including self-evaluation tests and small tasks
• Tasks completed before or after practical sessions
• Includes development of a basic network program as preparation for a final project
• Competences developed: B4, B6, B9, C11, C17, C18, C19, D2, D3, D4

Practices through ICT

• Development of small network programs individually and autonomously
• Sessions include explanation of programming concepts (sockets, network utilities)
• Support for debugging and evaluation in the laboratory
• Competences developed: B1, B6, B9, C11, C17, C19

Gamification

• Use of a gamification system in the virtual classroom (points, mechanics, rewards)
• Encourages participation in online activities and forums
• Rewards can be used in exams or continuous assessment
• Discussion forums serve as the main space for resolving doubts
• Promotes peer support and collaborative learning
• Enhances motivation and engagement
• Competences developed: B9, D3, D4

Assessment Methods and Criteria

Evaluation Activities

Autonomous problem solving

• Description: Weekly tasks, exercises, questions, and self-evaluation tests carried out individually and remotely via the virtual classroom, all with deadlines
• Qualification: 0–10 (counts as 10% only for Continuous Assessment Option B; for Option A it is only self-assessment)
• Training and Learning Results: B4, B6, B9, C11, C17, C18, C19, D2, D3, D4

Practices through ICT

• Description: Development of small network programs with support sessions (concept explanation, tutoring, debugging in lab)
• Evaluation: Program mark (0–10) multiplied by a related exam question (value between 0 and 1)
• Qualification: 10%
• Training and Learning Results: B1, B6, B9, C11, C17, C19

Essay questions exam (Final Exam)

• Description: Final exam covering the whole subject
• Qualification: 40% (minimum 3.5/10 required to pass)
• Training and Learning Results: B3, B4, C11, C17, C18, C19, D2

Objective questions exam

• Description: One-hour multiple-choice progress tests
• Qualification:
  • 20% (Option B – Continuous Assessment)
  • 25% (Option A – Continuous Assessment)
• Training and Learning Results: B3, B4, C11, C17, C18, C19, D2

Other Comments on the Evaluation

Assessment Types

• Continuous Assessment (CA)
• Global Assessment (EA)

Continuous Assessment (CA)

General Rules

• Two options: A and B
• Must be selected within the first month (before first control test)
• No selection → Global Assessment
• Option B requires a minimum group size of 30 students

Assessment Components

1. Online qualifying activities (Merit Points – MP)
   • Weekly tasks in the virtual classroom
   • Maximum: 100 points → normalized (MP/100)
   • Includes rewards and peer evaluation
   • Only counts for Option B
2. Network programs (PR)
   • Individual development of programs
   • Evaluated in lab sessions
   • Final contribution: PR × CR (CR = exam question factor between 0 and 1)
3. Control Tests (C1 and C2)
   • Two multiple-choice exams
   • Weight:
     • Option A: 25% each
     • Option B: 20% total contribution
   • Not recoverable (absence = 0)
4. Final Exam (FE)
   • Covers all contents
   • Weight: 40%
   • Minimum required: 3.5/10
   • Includes CR (program-related question, not directly counted but used as multiplier)

Final Grade Calculation

• Option A:
  • FG = 0.25 × (C1 + C2) + 0.1 × CR × PR + 0.4 × FE (if FE ≥ 3.5)
• Option B:
  • FG = 0.2 × (C1 + C2) + MP/100 + 0.1 × CR × PR + 0.4 × FE (if FE ≥ 3.5)
• If FE < 3.5 → Final grade = min(3.5, calculated FG)

Global Assessment (EA)

• Single final exam (FE) including CR
• Final grade:
  • FG = 0.9 × FE + CR

Extraordinary Exam

• New final exam (FE) including CR
• Best marks (ordinary vs extraordinary) are retained
• Continuous Assessment students may switch to Global Assessment (with prior notice)

End-of-Program Exam

• Same procedure as Global Assessment

Additional Rules

• Any student attending FE is considered “presented”
• All grades are valid only for the current academic year

Academic Integrity

• Plagiarism or dishonest behavior → FAIL (0) + report to authorities
• Virtual platform tools detect cheating and plagiarism

Communication

• All official communications published in the virtual classroom News Forum
• Students are assumed to be informed

Note on Language

• In case of discrepancies, the Galician version prevails (except for English groups, where the English version applies)