CREST Practitioner Security Analyst (CPSA) Practice

Which protocol is primarily used to prevent network loops by adopting a dynamic routing method?

1. STP

2. DHCP

3. VRRP

4. CDP

The correct answer is: STP

The protocol primarily used to prevent network loops by adopting a dynamic routing method is Spanning Tree Protocol (STP). STP is designed to detect and eliminate loops in a network topology that could lead to broadcast storms and other issues that degrade network performance. It works by creating a logical tree structure that spans all the switches in a network while blocking redundant paths, ensuring that there is only one active path between any two network devices. In this context, dynamic routing methods involve protocols that automatically adjust the paths data packets take through the network as changes occur, such as link failures or additions. However, while dynamic routing protocols like OSPF or EIGRP do not directly prevent loops, STP specifically addresses the loop issue within switched Ethernet networks. The other protocols listed serve different functions: DHCP (Dynamic Host Configuration Protocol) is responsible for assigning IP addresses to devices on a network; VRRP (Virtual Router Redundancy Protocol) provides high availability and failover for routers; and CDP (Cisco Discovery Protocol) is a network discovery tool used to gather information about the directly connected Cisco devices. None of these protocols are designed primarily for loop prevention in the context of network topology management.