A router is a networking device that forwards data packets between computer networks using headers and forwarding tables to determine the best path to forward the packets.

A mail transfer agent (MTA) is a software program or computer system that transfers electronic mail messages from one computer to another, using protocols such as SMTP.

The OSI (Open Systems Interconnection) model is a conceptual framework used to describe the functions of a networking system. It consists of 7 layers: Physical, Data Link, Network, Transport, Session, Presentation, and Application.

The Physical layer is responsible for the physical equipment involved in the transfer of data, such as cables, connectors, and specifies electrical, mechanical, and functional requirements.

The Network layer is responsible for logical addressing, routing, and determining the path for data transfer between source and destination nodes across multiple networks.

The Transport layer protocols include TCP (Transmission Control Protocol) and UDP (User Datagram Protocol), which handle data segmentation, flow control, and error correction.

The Internet Protocol (IP) is a core protocol of the Internet that operates at the Network layer. It is responsible for logical addressing, routing, and fragmenting data for transmission over packet-switched networks.

TCP is a connection-oriented protocol that ensures reliable data delivery through error checking and flow control mechanisms. UDP is a connectionless protocol with no inherent error checking, making it faster but less reliable than TCP.

A subnet mask is a 32-bit number that separates an IP address into the network and host portions, enabling efficient routing and allocation of IP addresses within a network.

A default gateway is a node or router on a computer network that serves as the forwarding host to other networks when no other route specification matches the destination IP address of a packet.

Network Address Translation (NAT) is a method of remapping one IP address space into another, allowing multiple devices to share a single public IP address for connecting to the Internet.

A firewall is a network security device or software that monitors and filters incoming and outgoing network traffic based on predetermined security rules to protect a network or individual host from unauthorized access.

A Virtual Private Network (VPN) is a secure, encrypted connection over the Internet between a device and a private network, allowing remote users to access network resources as if they were directly connected.

HTTP is an application-layer protocol used for transmitting hypermedia documents, such as HTML webpages, between a web browser and a web server over the Internet.

The Domain Name System (DNS) is a hierarchical and decentralized naming system that translates human-readable domain names (e.g., www.example.com) into numerical IP addresses that can be interpreted by computers.

A hub is a simple device that broadcasts data to all connected devices, whereas a switch is an intelligent device that directs data only to the intended recipient device based on MAC addresses.

The File Transfer Protocol (FTP) is a standard network protocol used for transferring computer files between a client and a server over a network.

A socket is a software endpoint that acts as an interface between an application and the network, enabling communication between two programs over a network.

A port number is a logical construct that identifies a specific process or service running on a computer to which network data can be sent or from which it can be received.

A man-in-the-middle attack is a type of cyberattack where an attacker secretly intercepts and relays messages between two parties, potentially altering the communication content.

A denial-of-service (DoS) attack is a type of cyberattack aimed at making a network resource unavailable to its intended users by overwhelming the target with a flood of traffic or requests.

A brute-force attack is a trial-and-error method used by attackers to crack encrypted data or gain unauthorized access by systematically trying all possible combinations of passwords or encryption keys.

A botnet is a network of compromised computers or devices infected with malware and controlled remotely by a cybercriminal, often used to carry out coordinated attacks or distribute spam.

A backdoor is a malicious program or code that allows unauthorized remote access to a computer system, bypassing security measures and granting control to an attacker.

A honeypot is a decoy system or resource designed to lure and detect cyber attackers and study their techniques and methods for defensive purposes.

A DMZ (demilitarized zone) is a physical or logical subnetwork that separates an organization's internal network from the external, untrusted network (such as the Internet), acting as a buffer zone for external-facing services.

A proxy server is a computer system or application that acts as an intermediary between a client and a server, forwarding client requests and returning responses from the server to the client.

A load balancer is a device or software that distributes network traffic across multiple servers or computing resources, optimizing resource utilization, maximizing throughput, minimizing response times, and avoiding overload.

A Content Delivery Network (CDN) is a geographically distributed network of proxy servers and data centers that provides fast and efficient delivery of web content, such as images, videos, and other static files, to end-users based on their geographical location.

A wireless access point (WAP) is a device that allows wireless devices to connect to a wired network, creating a wireless local area network (WLAN).

WEP, WPA, and WPA2 are wireless security protocols. WEP (Wired Equivalent Privacy) is an older, less secure protocol. WPA (Wi-Fi Protected Access) and WPA2 are more recent and secure protocols, with WPA2 being the most secure and widely used today.

A wireless ad-hoc network is a decentralized, self-configuring, and infrastructure-less network of wireless devices that communicate directly with one another without the need for a centralized access point or router.

A LAN (Local Area Network) is a computer network that spans a small geographical area, such as an office or building. A MAN (Metropolitan Area Network) covers a larger geographical area, like a city. A WAN (Wide Area Network) is a network that spans an even larger geographical area, often across countries or continents.

DHCP (Dynamic Host Configuration Protocol) is a network management protocol that automatically assigns IP addresses, default gateways, and other network parameters to client devices on a network, reducing the need for manual configuration.

Network segmentation is the practice of dividing a computer network into smaller, isolated subnetworks or segments, often used to improve security, performance, and manageability by controlling traffic flow between different parts of the network.

Network topology refers to the physical or logical arrangement of devices and connections within a computer network, such as bus, ring, star, mesh, or hybrid topologies, which impact factors like performance, reliability, and scalability.

A MAC (Media Access Control) address is a unique identifier assigned to a network interface controller (NIC) for use as a network address in communications within a network segment.

Network latency is the amount of time it takes for data to travel from one point to another on a network, measured as the delay between the transmission and reception of data packets.

Network bandwidth is the maximum amount of data that can be transferred over a network or internet connection in a given amount of time, typically measured in bits per second (bps).

Network congestion occurs when the network traffic exceeds the available network resources, leading to poor performance, packet loss, and increased latency.

A network interface card (NIC) is a hardware component that connects a computer or device to a network, enabling it to send and receive data over that network.

A repeater is a device that amplifies or regenerates signals in a wired or wireless network to extend the network's coverage area and distance between nodes.

A network bridge is a device that connects and forwards data between two or more network segments at the data link layer (layer 2) of the OSI model, based on MAC addresses.

Network convergence refers to the integration of various communication services and networks, such as voice, data, and video, onto a single unified network infrastructure.

Network virtualization is a method of combining available network resources by splitting up physical network devices into multiple virtual networks, each with its own logical topology and policies.

VoIP (Voice over Internet Protocol) is a technology that allows voice communications to be transmitted over internet or IP-based networks, enabling telephone calls to be made over a broadband internet connection instead of traditional analog telephone lines.

Network management is the process of administering, operating, and maintaining computer networks to ensure their availability, reliability, security, and performance through the use of specialized tools and protocols.

Unicast is one-to-one transmission, multicast is one-to-many transmission, and broadcast is one-to-all transmission within a network segment.