A routing table is used by a router (or sometimes by a computer) to decide where to forward packets. It contains information about the destination and how to reach it via the gateway.

2. Components of the Simplified Routing Table

In a basic routing table that only includes destination and gateway, here's what each column means:

3. What Goes in the Destination Column?

The Destination column specifies the network or host the router is trying to reach. It can contain:

1. Subnet:
   • Specifies an entire network.
   • Written in CIDR notation (e.g., 192.168.1.0/24 for a network or 10.0.0.0/8 for a large network).
2. Single Host:
   • Specifies a single device.
   • Written as an individual IP address (e.g., 192.168.1.10).
3. Default Route (0.0.0.0/0):
   • Acts as a "catch-all" for any destination not explicitly listed in the table.
   • Typically used to forward traffic destined for unknown networks to the internet.

4. What Goes in the Gateway Column?

The Gateway column specifies the next-hop router where the packet should be sent. It is:

1. IP Address of the Next-Hop Router:
   • The router that will handle forwarding the packet toward its destination.
   • Example: If you're trying to reach 8.8.8.8, your gateway might be 192.168.1.1.
2. Direct Connection:
   • If the destination network is directly connected to the router, the Gateway column is marked as `` or 0.0.0.0 (meaning "no gateway needed").

5. Example of a Routing Table

Explanation of the Example