The core of FES is a multi-gigabit forwarding engine capable of serving up to eight full-duplex gigabit Ethernet ports, thus forwarding eight gigabits of data every second. All the ports have four priority queues enabling four different priority levels. At congestion situation frames are discarded in WRED (Weighted Random Early Detection) fashion, which drops frames from low priority queues first, preserving the more important streams also during congestion. Using Store-and-Forward technique enables error-checking of the frames and eliminates the possibility of the switch forwarding broken frames, which is impossible for Cut-through type of switches. Forwarding latency is minimal, thanks to gigabit operation.