This read-only Gauge32, in bytes, reports the average frame size, transmitted and received, on Port 2 during this 15-minute long-term sample, with 4294967294 meaning unknown. An admin watches this value to detect shifts in traffic composition on Port 2, since a falling average frame size often means more small control or voice packets while a rising one suggests bulk data transfer. For example, an average frame size that suddenly drops toward 64 bytes on Port 2 during a 15-minute long-term sample suggests a flood of minimal-size frames, worth investigating alongside the accompanying Runts counter for that same interval.