OSI and TCP/IP Models

Course Description

• The course explores the OSI and TCP/IP layered models that are fundamental to understanding device communication.
• It analyzes the role protocols play in physical/logical addressing, network types, end-to-end connectivity, and application requirements.
• Key factors assessment in designing and building effective computer networks are developed.

Course Learning Outcomes

• CLO1: Demonstrate understanding of networking principles.
• CLO2: Implement enterprise network switching infrastructure.
• CLO3: Implement IP addressing and routing.
• CLO4: Apply protocols and standards for data communication.

Assessment Strategy

• In-class lab Activities are worth 30%, weeks 5-13 consisting of practical activities, covering CLOs 2, 3, and 4.
• Theory Exam is worth 20%, week 9 and covers CLOs 1, 2, and 3.
• PCQ is worth 10%, week 14 and consists of Cisco CCNA (Introduction to Networks).
• Practical Exam (FWA) is worth 40%, week 15 and is a final exam, covering CLOs 2, 3, and 4.

Recommended Reading

• Textbook: Bongsik Shin (2021), 'A Practical Introduction to Enterprise Network and Security Management', 2nd ed., Auerbach Publications, eText ISBN: 9781000418163.
• Course Notes: Lecture slides and labs are located on Bb Learn.
• A large number of electronic resources exist on the Internet including book chapters, academic papers, FAQs, online workshops, programs and other relevant material.

Delivery Outline

• Week 1: CLO1 - Explaining modern network technologies principles
• Week 2: CLO1 - Explaining network protocols and standards principles
• Week 3: CLO2 – Classifying network physical connectivity
• Week 4: CLO2 – Implementing media access control, and data link communication
• Week 5: CLO2 – Implementing Ethernets, and switched networks
• Week 6: CLO3 – Implementing Network layer IP protocols
• Week 7-8: CLO3 – Implementing IPv4 subnetting for network segmentation
• Week 9: CLO3 – Implementing IPv6 addressing
• Week 10: CLO4 – Classifying transport layer protocols operation for end-to-end communication
• Week 11: CLO4 – Classifying application layer protocols operation in end-user applications
• Week 12: CLO4 – Implementing network hardening features to enhance security
• Week 13-14: CLO2-4 – Designing and simulating a small network
• Week 15: CLO2-4 – Troubleshooting internetworking Devices

Objectives (Module 1)

• Students will be able to demonstrate understanding of network models, peer-to-peer networks and media types.
• Students will be able to demonstrate understanding of network topologies, the difference between the Internet, Intranets and Extranets
• Students will be able to demonstrate understanding of scales of networks, LANs and WANs, implementation considerations, QoS and VOIP.

Networks Connect Us - No Boundaries

• Networking technologies greatly impact lives by enabling the internet, real-time communications, global online communities, and cloud computing.

Host Devices

• Computers, tablets, or smartphones are hosts needed for network connectivity.
• Hosts need a unique IP address within a network and are also known as end devices.

Client-Server Networks

• End devices can be clients or servers.
• Clients use software to request/display information from servers (e.g., web pages, emails).
• Servers have software to provide information (email, web pages, files) to other end devices.

Peer-to-Peer Networks

• P2P networks lack a central device with complete control.
• The term "peer" denotes individuals of the same status.
• Every device authenticates users, checks a local security database and controls file/service access.
• Setup is easy, less complex and lower cost because it doesn't require a server.
• Limited size, performance, and security make it suitable for 10 or fewer users/devices.

Intermediary Network Devices

• These interconnect end devices such as switches, wireless access points, routers, and firewalls.
• An intermediary device manages data flow and can regenerate/retransmit signals.
• These devices maintain pathway information and notify of errors or communication failures.

Media Types

• Networks may include legacy cables (10 Mbps) and high-speed fiber (40 Gbps+).
• Cable includes: Coaxial cables (uses electrical impulses), Twisted pair cables (uses electrical impulses), Fiber optic cables (uses light pulses).
• Wireless uses modulation of specific frequencies of electromagnetic waves.

Network Topologies

• Networks use diagrams called network topologies to map different sizes and types of businesses.
• Physical topologies describe device connections.
• Logical topologies describe data travel.

Common Types of Networks

• Understanding the key characteristics of networks is vital to understanding terminologies like the Internet, Intranets, and Extranets

The Internet

• Refers to publicly available services and infrastructure outside of private networks.

Intranets

• The prefix "intra-" = means inside.
• Relates to network communication within a specific network.
• Services are restricted and require user/device authentication for privacy and inaccessibility from the internet.

Extranets

• Grants outside organizations access to a specific intranet.
• Access should only be given to trusted organizations or individuals, such as business partners.

Scales of Networks

• Networks are described by their deployment scale, based on the area they cover.

Understanding Local Area Networks

• LANs cover a small geographic area where devices are considered local.
• The internal infrastructure for most organizations will normally take the form of a local area network (LAN)
• LAN technologies must be understood to support and efficiently run the organization.

Understanding Wide Area Networks

• WANs cover large geographical areas and link multiple LANs.
• Infrastructure is hosted/controlled by third-party service providers due to size.

Implementation Considerations

• Factors for implementing any network include budget, skill set, existing infrastructure, hardware, environment, number of users, security, and network model.

Setting up a Broadband Connection

• Homes and small offices (SOHO) can use cable, DSL, wireless WAN, mobile services, or dial-up.
• Large organizations/enterprises can use leased lines, Metro Ethernet, Business DSL, or satellite.

Network Architecture

• Refers to the technologies supporting the infrastructure that moves data across the network.

Reliable Networks

• Fault Tolerance: Limits failure impact using multiple paths.
• Scalability: Quickly expands to support new users/applications.
• Quality of Service (QoS): Enables prioritization for services like video.
• Security: Protects infrastructure and data.

Fault Tolerance

• Limits the impact of failure using multiple paths.
• Providing redundancy with packet switching helps reliable networks.
• Packet switching splits traffic into packets routed over a network.
• Each packet can take a different path to the destination.
• Circuit switched networks which establish dedicated circuits do not support this.

Scalability

• A network can easily expand to support new users/applications without impacting existing services.
• Standards and protocols are followed to make networks scalable.

Quality of Service (QoS)

• Ensures that video transmissions require higher expectations for service delivery.
• Helps routers prioritize network traffic.
• Data includes ToS or DiffServ indicators for routers identify and prioritize traffic types.
• Without QoS, issues like buffering can occur.

Network Security

• Network infrastructure include physical security of network devices and preventing unauthorized access.
• Information Security involved protection of data transmitted over the network.
• The three main goals are confidentiality, integrity, and availability.

Voice Over IP (VoIP)

• Requires QoS for efficient operation.
• Buffering/delay makes VoIP and teleconferencing impractical.

The Converging Network

• Before, organizations used separate cables for telephone, video, and data.
• Each network used different technologies and standards.