What does PAgP stand for?

PAgP stands for Port Aggregation Protocol. It is a Cisco proprietary protocol that is used to automate the aggregation of multiple Ethernet links into a single logical link. This is useful for increasing bandwidth and providing redundancy between switches or other devices. By employing PAgP, network devices can negotiate automatically to form a link aggregation group (LAG), which consolidates multiple physical interfaces into one logical interface, promoting effective load balancing and enhanced fault tolerance.

The correct answer aligns with the proper use and definition of the protocol within the context of networking, specifically in Cisco environments where link aggregation is implemented to optimize performance and reliability.