Poe switch rackmount switch switching ports 28 gigabit ethernet ports 24 x rj 45 4 x sfp switch type standalone management managed layer 2 network standards spanning tree protocol stp port mirroring igmp snooping vlan quality of services qos full duplex link layer discovery protocol lldp link aggregation lag link aggregation control protocol lacp weighted round robin wrr mld snooping loop detection backplane bandwidth 56 gbs packet forwarding rate