Abstract: A system may include a bus carrying signals, a frame pulse generator generating a generally periodic frame pulse signal having timing boundaries delineating consecutive timing periods and a frame pulse enable signal active for a portion of each timing period proximate to the timing boundaries and inactive otherwise, a first controlled buffer driving the frame pulse signal on the bus during durations in which the frame pulse enable signal is active to generate a modified frame pulse, a reference clock controller receiving the modified frame pulse via the bus and generating a reference clock enable signal in response to presence of the modified frame pulse, a reference clock generator generating a generally periodic reference clock signal, and a second controlled buffer driving the reference clock signal on the bus during durations in which the reference clock enable signal is active to generate a modified reference clock.

Abstract: A system may include a bus carrying signals, a frame pulse generator generating a generally periodic frame pulse signal having timing boundaries delineating consecutive timing periods and a frame pulse enable signal active for a portion of each timing period proximate to the timing boundaries and inactive otherwise, a first controlled buffer driving the frame pulse signal on the bus during durations in which the frame pulse enable signal is active to generate a modified frame pulse, a reference clock controller receiving the modified frame pulse via the bus and generating a reference clock enable signal in response to presence of the modified frame pulse, a reference clock generator generating a generally periodic reference clock signal, and a second controlled buffer driving the reference clock signal on the bus during durations in which the reference clock enable signal is active to generate a modified reference clock.

Abstract: A system for downloading a software image to a SONET network element which eliminates the need for a separate overhead channel for this purpose. The system conveys the software image using the File Transfer Protocol (FTP) over the Transmission Control Protocol (TCP), over the Internet Protocol (IP), using ATM. The disclosed system enables ATM cells carrying the software image to be received over a SONET ring connected to the device. The disclosed system uses permanent virtual circuits (PVCs) between network elements over which the software image may be transported. In a first embodiment, the PVCs form a star of logical connections with remote network elements to which software image files may be downloaded from a “gateway” network element. The gateway network element is a network element communicative with a central management station, which provides data to be downloaded to the remote network elements.