CCNA Quick Reference Sheets (CCNA Exam 640-802)

Section 4. Routing Operations and VLSM

Routing Overview

Routing is the process of getting packets and messages from one location to another.

A router needs the following key information, as displayed in Figure 4-1:

• Destination address: The destination (typically an IP address) of the information being sent. This includes the subnet address.

• Possible routes: Likely routes to get from source to destination.

• Best route: The best path to the intended destination.

• Status of routes: Known paths to destinations.

Figure 4-1. Information Needed by Router for Routing

A router is constantly learning about routes in the network and storing this information ...