Cisco Certified Network Associate (CCNA) Practice Exam

What do router advertisements include in relevant configurations?

1. IP addressing information

2. Routing loop prevention

3. Community string details

4. Host DNS settings

The correct answer is: IP addressing information

Router advertisements, particularly in the context of IPv6 and the Neighbor Discovery Protocol (NDP), serve as a fundamental mechanism for distributing important configuration information to devices on the same local network. One of the primary contents of these advertisements is the IP addressing information which includes the prefix, the preferred and valid lifetime of the address, and whether the device should use Stateless Address Autoconfiguration (SLAAC) to generate its own IP address based on the advertised prefix. Through these advertisements, routers announce the networks they are associated with, enabling hosts to configure their own IP addresses automatically without the need for manual configuration or a DHCP server. This process optimizes network management and allows devices to join the network seamlessly by acquiring necessary addressing information directly from the router. The other options provided, while essential concepts in networking, do not relate directly to the contents of router advertisements. Routing loop prevention pertains to mechanisms like Split Horizon and Poison Reverse to prevent routing loops, community strings are associated with SNMP for managing network devices, and host DNS settings typically involve manual or DHCP-facilitated configurations rather than being part of router advertisements.