Network Programming: Lecture 01

• Network programming is explored in Lecture 01
• Prerequisites include basic C++ programming, understanding operating systems, and knowledge of computer networks

Modules Covered

• Introduction to network programming
• TCP and UDP socket programming
• Advanced socket programming
• Application-level protocols
• Network performance and security

Outcomes

• Students should understand computer networks and various protocols
• Students will understand the World Wide Web concepts
• Students will be able to administer a network and flow of information
• Students can easily understand the concepts of network security and mobile

Network Overview

• Layering enables service abstraction through problem decomposition, modular design, and interoperability
• OSI principles include different levels of abstraction, well-defined functions and interfaces, open system support, and different functions in different layers

Networking Concepts

• A network is a collection of interconnected devices (computers, servers, routers) that share resources and data
• A node is any device (computer, printer, router) connected to a network
• A protocol is a set of rules for data transmission over a network (e.g., TCP/IP, HTTP, FTP)
• An IP address is a unique numerical identifier assigned to each device on a network for communication
• A MAC address is a hardware address assigned to a network interface card (NIC) for device identification
• LAN means local area network which is confined to a small area like a home or office
• WAN means wide area network and covers large geographic areas like the internet
• A router directs data packets between different networks
• A switch connects multiple devices within a LAN and forwards data based on MAC addresses
• A firewall monitors and controls network traffic based on security rules

IP Address

• Enables devices to send and receive data over the network by identifying their location
• Ensures that data reaches the correct destination in a networked environment

Types of Networks

• LAN (Local Area Network) is a small, single location network for a home or office
• WAN (Wide Area Network) is for large, multiple locations like the internet
• MAN (Metropolitan Area Network) is city-wide
• PAN (Personal Area Network) includes Bluetooth and smartwatches

Network Components

• Hosts, networking devices, communication media, and protocols are components included in networks
• Hosts include computers, servers, and IoT devices
• Networking devices include routers, switches, and hubs
• Communication media includes cables and wireless signals
• Protocols include TCP/IP, HTTP, and FTP

OSI Model

• The Open Systems Interconnection (OSI) Model is a conceptual framework for network communication
• It divides communication into 7 layers and ensures interoperability

OSI Model Layers

• Application Layer for end-user interaction (HTTP, FTP)
• Presentation Layer for data encryption & formatting (SSL, JPEG)
• Session Layer for session establishment (RPC, SQL)
• Transport Layer for reliable data transfer (TCP, UDP)
• Network Layer for routing & addressing (IP, Routers)
• Data Link Layer- MAC addressing, error detection (Ethernet)
• Physical Layer - Transmission of raw bits (Cables and Wi-Fi)

OSI Model Overview

• Application Layer is the human-computer interaction layer, where applications access network services
• Presentation Layer ensures data is in a usable format and handles data encryption
• Session Layer maintains connections and controls ports and sessions
• Transport Layer transmits data using protocols like TCP and UDP
• Network Layer decides the physical path data takes
• Data Link Layer defines the format of data on the network
• Physical Layer transmits raw bit stream over the physical medium

TCP/IP

• The Transmission Control Protocol/Internet Protocol (TCP/IP) is the foundation of the Internet and modern networks

TCP/IP Model Overview

• Application Layer enables user-level applications (HTTP, FTP, SMTP)
• Transport Layer ensures reliable data delivery (TCP, UDP)
• Internet Layer handles IP addressing and packet routing
• Network Access Layer manages physical network transmission