The modem connects to the ISP and provides the internet signal. The router connects to the modem to manage the connection, provide DHCP, and act as a firewall. The switch then connects to the router to expand the number of available ports for the end devices. Connecting the switch before the router would prevent the router from managing the internal network traffic.

RAM (Random Access Memory) is volatile memory used for temporary storage of the running configuration, routing tables, and ARP cache. ROM (Read-Only Memory) is non-volatile and stores the bootstrap program and a limited backup IOS image, which are essential for the device’s initial startup and recovery.

Networked printers, servers, and other critical infrastructure devices are typically configured with static IP addresses. This ensures their address never changes, making them reliably accessible by users and other network devices, unlike dynamic addresses from a DHCP server which can change over time.

NAT allows multiple devices on a private network (with private IPs like 192.168.1.x) to share a single public IP address provided by the ISP. The router translates the laptop’s private source IP to its own public IP when sending the request to the internet, and translates the returning traffic back to the laptop’s private IP.

An IP address in the 169.254.x.x range is an Automatic Private IP Address (APIPA) assigned by the operating system when a DHCP client fails to contact a DHCP server. The computer can communicate locally (printer, other PCs) but has no valid gateway or DNS to reach the internet.

When connecting two similar devices (e.g., computer-to-computer or switch-to-switch) directly, a crossover cable is required to properly align the transmit and receive pairs. A straight-through cable is used for connecting dissimilar devices (e.g., computer-to-switch). Modern devices often have Auto-MDI/MDIX to correct this automatically, but it’s a fundamental concept.

The default gateway is the IP address of a router interface on the same local network. When a host needs to send data to an IP address that is not on its local subnet, it forwards that data to its default gateway. The router then uses its routing table to send the data toward the destination network.

A traditional switch operates at Layer 2. It builds a MAC address table that maps MAC addresses to switch ports and uses this table to forward frames only to the specific port where the destination device is located, reducing network collisions. A hub (Layer 1) repeats signals to all ports, and a router (Layer 3) uses IP addresses.

WEP (Wired Equivalent Privacy) is an outdated and cryptographically weak protocol that can be broken in minutes. WPA2 (Wi-Fi Protected Access 2) mandates the use of the strong AES (Advanced Encryption Standard) encryption protocol, providing robust security for wireless data. WPA3 is the newer, recommended standard.

The modem connects to the ISP and provides the internet signal. The router connects to the modem to manage the connection, provide DHCP, and act as a firewall. The switch then connects to the router to expand the number of available ports for the end devices. Connecting the switch before the router would prevent the router from managing the internal network traffic.0