As described, this CienaGlobalState object toggles the cienaCesRstpPortOperEdgeNotification trap, which is generated when a port's RSTP operational edge status changes. Edge ports skip the RSTP listening/learning delay and forward immediately, so a change from edge to non-edge, usually triggered by receiving a BPDU on a port configured as an edge port, means a switch or hub was unexpectedly connected where only an end device was expected. A server-room admin would use this trap to catch someone plugging a switch into a port meant only for a server NIC, which could otherwise silently introduce forwarding delay or a loop.