Chapter 1_ Introduction to Data Communications.pdf

Chapter 1: Introduction to Data Communications PowerPoint: CIS3347_13e_Ch01_IntroDataComm v1.3 (1).pdf Introduction Data communications networks are essential for data exchange between devices across distances. Networks enable communication across local area networks (LANs), wi...

Chapter 1: Introduction to Data Communications PowerPoint: CIS3347_13e_Ch01_IntroDataComm v1.3 (1).pdf Introduction Data communications networks are essential for data exchange between devices across distances. Networks enable communication across local area networks (LANs), wide area networks (WANs), and the Internet, supporting business operations, personal communications, and global data sharing. Data Communications Networks Components of a Network Servers: Computers that store and distribute data to clients. Clients: Devices like computers or smartphones that access data from servers. Circuit: The physical or logical connection between devices, enabling data transfer. Routers and Switches: Direct data to the correct destination by determining the optimal path. Types of Networks Local Area Network (LAN): A network within a small geographic area, such as a building. Wide Area Network (WAN): Covers a larger geographic area, typically consisting of multiple LANs connected via routers and using leased lines. Metropolitan Area Network (MAN): A network that spans a city or campus. Personal Area Network (PAN): A small network typically used for personal devices, like Bluetooth or home Wi-Fi. Network Models Network models provide a framework for understanding how data moves across different layers in a network. Open Systems Interconnection Reference Model (OSI Model)  A seven-layer model created by ISO to standardize network communication. ○ Layers: Physical, Data Link, Network, Transport, Session, Presentation, and Application. ○ Each layer has specific functions for managing data transfer, from physical connections to application-level services. Internet Model The TCP/IP model is the foundation of modern networks, especially the internet. ○ Layers: Network Interface, Internet, Transport, and Application. ○ It simplifies the OSI model and focuses on the protocols driving the internet. Message Transmission Using Layers When a message is transmitted over a network, it passes through each layer, gaining additional information (headers) at each layer. On the receiving end, these headers are stripped off, and the message is passed to the appropriate application. Network Standards Standards ensure that devices and networks built by different manufacturers can communicate efficiently. The Importance of Standards Standards ensure interoperability between devices, providing consistent rules for how data is transmitted, managed, and received. The Standards-Making Process Organizations like ISO (International Organization for Standardization) and IEEE (Institute of Electrical and Electronics Engineers) develop and approve standards. De facto standards emerge naturally through widespread use, while formal standards are ratified through a rigorous process. Common Standards IEEE 802.3 (Ethernet): A standard for wired LANs. IEEE 802.11 (Wi-Fi): A standard for wireless LANs. TCP/IP: A suite of protocols that governs the transmission of data across the internet. Future Trends Emerging trends are shaping the future of networking, particularly in wireless and internet-based systems. Wireless LAN and BYOD (Bring Your Own Device) Wireless LANs provide mobility and ease of access. BYOD policies allow employees to use personal devices on corporate networks, raising concerns about security and device management. The Internet of Things (IoT) IoT involves connecting everyday devices to the internet, enabling automation and data exchange (e.g., smart homes, connected cars). It poses challenges for network scalability, bandwidth, and security. Massively Online The growth of massively online platforms, such as cloud computing, social media, and online gaming, has led to increasing demand for bandwidth and reliable connectivity. Implications for CyberSecurity As networks evolve, so do security risks. Cybersecurity is a growing concern, requiring protection against threats like: ○ Data breaches, malware, and denial-of-service (DoS) attacks. ○ Encryption and firewalls: Essential tools for securing network communications. ○ Access control: Policies to restrict who can access the network and which resources they can use. Key Concepts to Remember Network Components: Servers, clients, circuits, and network devices like routers and switches. Types of Networks: LAN, WAN, MAN, and PAN. OSI vs. TCP/IP Models: Understand the functions of each layer in these models. Standards: Ensure interoperability between different network systems and devices. Future Trends: Wireless LANs, IoT, and massively online platforms are shaping the future of data communications. Cybersecurity: New technologies introduce new security risks, making encryption, firewalls, and secure access control more critical than ever.