CompTIA Network+ (N10-008) - Network Concepts & Troubleshooting

A router connects different networks (e.g., a local area network to the internet) and forwards data packets between them based on IP addresses. It operates at Layer 3 (Network Layer) of the OSI model.

A switch connects devices within the same local area network (LAN). It forwards data frames to specific devices based on their MAC addresses, improving network efficiency compared to a hub. It operates at Layer 2 (Data Link Layer) of the OSI model.

A firewall monitors and controls incoming and outgoing network traffic based on predetermined security rules. It acts as a barrier between a trusted internal network and untrusted external networks (like the internet), preventing unauthorized access.

An Access Point (AP) allows wireless devices to connect to a wired network. It acts as a central hub for wireless clients, converting wireless signals into wired signals and vice-versa, extending network access without cables.

HTTP is an application-layer protocol for transmitting hypermedia documents, such as HTML. It is the foundation of data communication for the World Wide Web, defining how clients (like web browsers) request and servers respond to web pages.

HTTPS is the secure version of HTTP. It uses SSL/TLS encryption to secure communication between a web browser and a website, protecting data integrity and confidentiality (e.g., for online banking or shopping). It typically uses port 443.

DNS translates human-readable domain names (e.g., google.com) into machine-readable IP addresses (e.g., 172.217.160.142). It's often called the 'phonebook of the internet' and is crucial for web browsing and email.

DHCP automatically assigns IP addresses and other network configuration parameters (like subnet mask, default gateway, and DNS server) to devices on a network. This simplifies network administration and prevents IP address conflicts.