Networking

📡 Network Device: Wireless Access Point (AP) A Wireless Access Point (AP) is a networking device that allows Wi-Fi-enabled devices to connect to a wired LAN. It operates primarily at the Data Link Layer (Layer 2) of the OSI model but interacts with the Physical Layer (Layer 1) as well. 🔹 What is an Access Point? An Access Point is like a wireless switch. It connects wireless clients (like laptops, phones) to a wired network and extends network access to areas without Ethernet cables. ...

📡 Network Device: Transceiver A Transceiver (short for Transmitter + Receiver) is a device used in networking to transmit and receive data signals. It operates at the Physical Layer (Layer 1) of the OSI model and plays a key role in converting electrical signals for network communication. 🔹 What is a Transceiver? A Transceiver is a hardware component that enables a device to send and receive signals over a network medium. It acts as an interface between the network medium (like copper, fiber, or wireless) and the networking device (like a NIC or router). ...

🔌 Network Device: Modem A Modem (Modulator-Demodulator) is a device that operates at the Physical Layer of the OSI model. It is used to convert digital data to analog signals and vice versa, enabling digital devices to communicate over analog communication channels like telephone lines. 🔹 What is a Modem? A Modem is a device that modulates digital data from a computer into an analog signal for transmission over telephone lines (or similar media) and demodulates analog signals back into digital data at the receiving end. This is crucial for Internet access, particularly in older or rural areas where traditional broadband services (like fiber or cable) are unavailable. ...

🔌 Network Device: Repeater A Repeater is a simple networking device that operates at Layer 1 (Physical Layer) of the OSI model. It is used to extend the range of a network by amplifying or regenerating signals over long distances. 🔹 What is a Repeater? A Repeater is a device that receives weak or degraded signals from a network, amplifies or regenerates them, and then retransmits the stronger signal. This is particularly useful in large networks or environments where signal loss occurs due to distance or physical obstacles. ...

🔌 Network Device: Hub A Hub is a basic networking device that operates at Layer 1 (Physical Layer) of the OSI model. It is used to connect multiple devices in a LAN (Local Area Network) by broadcasting data to all connected devices. 🔹 What is a Hub? A Hub is a simple, non-intelligent device that connects multiple computers or devices within a LAN. Unlike a switch or bridge, a hub does not filter or direct traffic based on MAC or IP addresses. It broadcasts incoming data to all ports, regardless of the destination, which can lead to inefficiencies in larger networks. ...

🔌 Network Device: Bridge A Bridge is a networking device that operates at Layer 2 (Data Link Layer) of the OSI model. It is used to connect two or more network segments within a local area network (LAN), helping to filter traffic and reduce collisions. 🔹 What is a Bridge? A Bridge is a device used to divide large networks into smaller segments. It helps in controlling traffic between segments, increasing the efficiency of network communications. Unlike a hub or a switch, which broadcasts data to all devices, a bridge forwards data only to the segment where the destination device is located, improving network performance. ...

🔌 Network Device: Router A Router is a networking device that operates at Layer 3 (Network Layer) of the OSI model and is responsible for routing data packets between different networks. It uses IP addresses to determine the best path for data transmission. 🔹 What is a Router? A Router connects different networks together and manages traffic between them. For example, it connects a local area network (LAN) to the internet (a wide area network, WAN) and forwards data packets between them. Routers also assign local IP addresses to devices within a network. ...

🔌 Network Device: Switch A Switch is a networking device that operates primarily at Layer 2 (Data Link Layer) of the OSI model, though some switches can also function at Layer 3 (Network Layer). 🔹 What is a Switch? A Switch is an intelligent device used in LANs to connect multiple devices (like computers, printers, and servers). It uses MAC addresses to forward data only to the intended recipient, making communication more efficient compared to hubs. ...

Layered Network Protocol Architectures: OSI and TCP/IP Protocol architectures organize communication tasks into layers. Each layer handles a specific function, ensuring modularity, easier troubleshooting, and interoperability. 🔹 What is a Protocol Stack? A protocol stack is a collection of network protocols layered to work together. Each layer performs a specific function and interacts with layers directly above and below. 🔹 OSI Model (Open Systems Interconnection) The OSI model is a theoretical model developed by ISO to standardize networking. ...

Introduction to Computer Networking Concepts Computer networking connects computing devices to enable data sharing and communication. This foundation supports services like the internet, file sharing, and cloud computing. 🔹 Purposes of Digital Communication and Computer Networks Resource Sharing: Access shared printers, files, storage. Communication: Email, chat, video conferencing. Remote Access: Control systems across locations. Centralized Data: Easier management and backups. Efficiency: Distributed workloads and services. 🔹 Types of Digital Communication and Computer Networks Network Coverage Area Example PAN Personal range (~10 meters) Bluetooth headset LAN Building or campus Home/office Wi-Fi MAN Citywide University networks WAN Country or global Internet 🖼️ Textual Diagram - Network Scale PAN < LAN < MAN < WAN 🔹 Network Components End Devices: Users’ computers, phones. Network Devices: Switch: Connects devices in a LAN (uses MAC address). Router: Connects different networks (uses IP). Modem: Converts digital ↔ analog for ISP. Hub: Broadcasts data to all ports (no intelligence). Bridge: Connects LAN segments, filters by MAC. Repeater: Regenerates weak signals. Access Point: Provides Wi-Fi access. Network Interface Card (NIC): Hardware to connect devices to a network. Transceivers: Send and receive signals over media. Transmission Media: Wired: Ethernet (Cat6), Fiber. Wireless: Wi-Fi, 4G/5G, Bluetooth. 🖼️ Textual Diagram - Basic LAN Setup [PC]---+ | [PC]---+--[SWITCH]---[ROUTER]---[INTERNET] | [Printer] 🔹 Communication Modes Mode Description Example Simplex One-way only Keyboard to PC Half Duplex Two-way, one at a time Walkie-talkies Full Duplex Two-way, simultaneous Phone calls 🖼️ Textual Diagram - Duplex Modes Simplex: A ---> B Half-Duplex: A <--> B (one at a time) Full-Duplex: A <===> B (simultaneous) 🔹 Transmission Types Unicast: One-to-one Broadcast: One-to-all Multicast: One-to-selected Anycast: One-to-nearest 🖼️ Textual Diagram - Broadcast vs Unicast Unicast: [Sender] ---> [Receiver] Broadcast: [Sender] ---> [All Devices on Network] Multicast: [Sender] ---> [Group of Devices] Anycast: [Sender] ---> [Nearest Suitable Receiver] 🔹 Communication Models Peer-to-Peer (P2P): ...