The Application Layer (Layer 7 of the OSI model) provides the interface for end-users and applications to communicate over a network. Elaboration: Example: When you visit a website, the Application Layer (HTTP/HTTPS) ensures that web content is displayed correctly in your browser.

The Transport Layer (Layer 4 of the OSI model) is responsible for end-to-end communication, error handling, and flow control between devices. Elaboration: Example: When loading a website, the Transport Layer ensures that all TCP packets are received and reassembled in the correct order.

The Network Layer (Layer 3 of the OSI model) is responsible for routing packets between different networks using logical addressing (IP addresses). Elaboration: Example: A router operates at the Network Layer by forwarding packets from one network to another using IP addresses.

The Data Link Layer is Layer 2 of the OSI model, responsible for node-to-node data transfer and error detection/correction. Elaboration: Example: In Ethernet networks, the Data Link Layer ensures that data packets are sent to the correct MAC address within a LAN.

Ethernet is a wired networking technology that allows devices to communicate within a local area network (LAN) using physical cables. Elaboration: Example: A desktop computer is connected to a router using an Ethernet cable for a stable internet connection.

Bluetooth is a short-range wireless communication technology used for exchanging data between devices over a short distance. Elaboration: Example: A user connects their wireless headphones to a smartphone via Bluetooth.

Wi-Fi is a wireless networking technology that allows devices to connect to the internet using radio waves instead of wired connections. Elaboration: Example: A smartphone connects to the home Wi-Fi network using a router that provides internet access.

SSL (Secure Sockets Layer) and TLS (Transport Layer Security) are cryptographic protocols that encrypt data transmission over networks to ensure security and privacy. Elaboration: Example: A bank’s website (https://bank.com) uses TLS to encrypt user transactions, ensuring security. To check a website’s certificate:

ARP (Address Resolution Protocol) maps an IP address to a device’s MAC address within a local network. Elaboration: Example: If a computer wants to communicate with 192.168.1.1, it uses ARP to find the MAC address associated with that IP. To check the ARP table on Windows, run: arp -a

A MAC (Media Access Control) address is a unique identifier assigned to a device’s network interface card (NIC) for communication within a local network. Elaboration: Example: A laptop’s Wi-Fi adapter has a unique MAC address used by routers to assign local network IPs. To find your MAC address on Windows, run: bashCopyEditipconfig /all