How does EIGRP prevent routing loops in its operations?

EIGRP prevents routing loops through the implementation of the Diffusing Update Algorithm (DUAL). DUAL is a key feature of EIGRP that enables it to efficiently manage routing information and maintain loop-free routes. It allows EIGRP routers to calculate the best path to a destination while also keeping track of backup routes, which facilitates rapid convergence and minimizes the potential for loops.

The DUAL process works by keeping a topology table that contains the state of all known routes, along with metrics that indicate their viability. When a route becomes unavailable, DUAL quickly identifies alternate routes to ensure continuous network connectivity without risking the formation of loops. This mechanism is crucial for EIGRP’s capability to provide reliable and stable routing in dynamic network environments.

In contrast, the other options represent differing mechanisms that do not specifically address the loop prevention as effectively as DUAL does. For instance, while distance vector mechanisms are used in some routing protocols, they are more prone to routing loops if not implemented with appropriate safeguards. Similarly, the augmented path vector algorithm and spanning tree protocol serve different purposes and do not apply directly to EIGRP's method of preventing routing loops. Thus, DUAL stands out as the correct choice for maintaining loop-free routing in EIGRP operations