Patent ID: 6870877
Filing Date: 2005-03-22
Classification: H04J

Abstract:
1. A transmission unit which transmits and receives digital signals over a first and second network systems, comprising: (a) a first signal interface means for receiving a first network signal and converting the received first network signal into a first internal signal with a fixed bit rate, and for sending an outgoing first network signal which is converted from a given second remapped internal signal with the same fixed bit rate; (b) a second signal interface means for receiving a second network signal and converting the received second network signal into a second internal signal with the fixed bit rate, and for sending out an outgoing second network signal which is converted from a given first remapped internal signal with the same fixed bit rate; (c) a two-way signal conversion means for making conversions between the first and second network signal, comprising: (d) a switching means for providing and controlling circuit paths to route the first internal signal, the second internal signal, the first remapped internal signal, and the second remapped internal signal; and wherein said two-way signal conversion means makes the conversions between the first and second network signals which include at least one of: two-way conversions between Synchronous Digital Hierarchy(SDH) signals and Synchronous Optical Network(SONET) signals; two-way conversions between Plesiochronous Digital Hierarchy(PDH) signals; and two-way conversions between Asynchronous Transfer Mode(ATM) signals.