A CIDR notation of /16 in an IPv4 address means that the first 16 bits are used for the network prefix. This notation is used to represent the subnet mask and the network prefix in IPv4 addresses.

When devices on the network send data to an unexpected MAC address while the IP address is correct, it could be indicative of ARP (Address Resolution Protocol) Spoofing. ARP Spoofing is a type of attack where an attacker associates their MAC address with another device's IP address, redirecting traffic meant for that IP address to the attacker's system. This can lead to a security breach. DNS Hijacking, IP Spoofing, and Packet Fragmentation are different issues with distinct characteristics.

In an Ethernet network, the MAC address is typically 48 bits (6 bytes) in length. It is usually represented as a series of 12 hexadecimal characters, separated by colons or hyphens.

A PAN (Personal Area Network) typically covers a smaller area, focusing on individual or immediate vicinity connections, such as connecting a smartphone to a laptop via Bluetooth. In contrast, a LAN (Local Area Network) serves a more extensive area, typically within a building or campus, connecting devices for personal and business use.

In a Star Topology, if one node fails, it does not affect the rest of the network. Each device is directly connected to a central hub or switch, so the failure of one device does not impact the others.

Port Numbers are responsible for directing a piece of data to a specific process running on a machine. Ports allow multiple processes on the same machine to use network resources simultaneously.

BGP (Border Gateway Protocol) is a path vector routing protocol used on the internet for routing between different autonomous systems. It's crucial for inter-domain routing and helps in making core routing decisions.

The primary purpose of flow control in computer networks is to prevent data loss and overwhelming receivers. Flow control mechanisms and methods help regulate the pace of data transmission to ensure that the receiver can process and acknowledge data effectively, preventing network congestion and data loss.

Coaxial Cable is commonly used for cable TV. It is susceptible to electromagnetic interference due to its copper core and outer shielding. This interference can affect signal quality, but its affordability and bandwidth make it a popular choice for cable television.

To achieve redirection from "www.example.com" to "example.com," the startup should configure a CNAME (Canonical Name) record. A CNAME record points one domain name to another, effectively allowing multiple domain names to resolve to the same website.