Here are the different networks within RFC1918 and their respective sizes:
IP segments can be divided into smaller networks, each featuring a reserved broadcast address used to send data to all hosts; this address is the last IP in the segment (e.g., in the 192.168.0.0/24 network, the broadcast address is 192.168.0.255).
The smallest netmask is 255.255.255.255 (or /32), allowing only one IP address, while the localhost address (127.0.0.1) facilitates communication between applications and belongs to a /8 network.
Routing traffic in IP networks is handled by routers, which forward packets between networks, unlike switches that function within a single network.
Packets on the network include headers that contain important details related to the IP protocol. Here’s an illustration of the IPv4 header:
The Source Address in the IP header identifies the sending system’s IP address, while the Destination Address indicates the recipient. The header includes additional fields for various IP features, which are beyond the scope of this introductory class.
To check your IP address, use the command ipconfig on Windows, or ip addr show or ifconfig on Linux. When communicating with a device outside the local area network (LAN), a computer sends traffic to the default gateway, usually a router set to forward traffic to the destination IP address.