Patent ID: 6891862

Claim:
A method of assembling a frame structure of a SDH signal at a hierarchy level N, comprising: receiving a hierarchically multiplexed administrative unit AU-n comprising an AU-n payload and an AU-n pointer; transforming said AU-n into a tributary unit TU-n having a TU-n payload and a TU-n pointer such that said AU-n becomes said TU-n, said transforming including transforming said AU-n payload of said AU-n into the TU-n payload of said TU-n and transforming said AU-n pointer of said AU-n into said TU-n pointer of said TU-n; and hierarchically multiplexing said TU-n into said frame structure, where n≧3, and gives the granularity of said SDH signal, and said AU-n pointer transformed into said TU-n pointer provides the beginning of said TU-n payload with respect to said frame structure.