Dell PowerEdge FN I/O Module Configuration Guide 9.10(0.0)

Link aggregation is defined by IEEE 802.3ad as a method of grouping multiple physical interfaces into a single logical interface—a link aggregation group (LAG) or port channel.

A LAG is “a group of links that appear to a MAC client as if they were a single link” according to IEEE 802.3ad. In the Dell Networking OS, a LAG is referred to as a port channel interface.

A port channel provides redundancy by aggregating physical interfaces into one logical interface. If one physical interface goes down in the port channel, another physical interface carries the traffic.