Abstract: A method and apparatus for discovering network paths sets a bit, normally used for purposes other than tracing a network path, in an overhead portion of a signal for causing state changes at nodes along a network path. The state changes are correlated with information about the signal to determine link connectivity between nodes to identify the network path. In a network of DS3 circuits, a non-critical alarm bit is set in a signal to transmit Remote Alarm Indications (RAI) which activate alarms at nodes of the network path. A response signal from the nodes can be sent through a network to a main node for correlation purposes. The method of discovering network paths can be used to update network path databases of network carriers and can be offered as a service to network carriers.

Abstract: A cord reel assembly is provided which maintains a length of stationary wire and a length of shielded retractable wire around a spool. The assembly dispenses the retractable wire as an attached handset is extended away from the assembly, while the stationary wire is concurrently being wound. A portion of the stationary wire internal to a housing enclosure is unshielded, while a portion extending outside the housing enclosure is shielded. The unshielded stationary wire is shielded by applying conductive paint or electroplating to the housing enclosure, thereby reducing EMI emissions. A spring cover retains a recoil spring and provides a bearing surface against a spindle member. The winding direction of the stationary and retractable wires is chosen, and the stationary wire conductors are arranged with shield ground wires, such that EMI emissions are reduced.