This document provides an overview of Synchronous Optical Network (SONET), represented in images.
Note: Tables and diagrams courtesy of JDS Uniphase Corporation
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This document is not restricted to specific software and hardware versions.
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This section provides an overview of SONET in a graphical format.
Figure 1 shows what a SONET link looks like.
Figure 1 – A SONET Link
Figure 2 shows the Synchronous Transport Signal level 1 (STS-1) frame structure.
Figure 2 – STS-1 Frame Structure
Figure 3 shows the STS-1 Transport and Path Overhead (SONET Overhead).
Figure 3 – STS-1 Transport and Path Overhead
Figure 4 looks at OC-12 concatenation.
Figure 4 – OC-12 Concatenation
Figure 5 displays the SONET hierarchy.
Figure 5 – SONET Hierarchy
Figure 6 shows how SONET maintenance interactions appear.
Figure 6 – SONET Maintenance Interactions
Table 1 lists what the alarms mean, and their detection criteria.
Table 1 – Meaning of Alarms and their Detection Criteria
Figure 7 and Figure 8 provide a description of all the bytes from STS-1 SOH, Line OverHead (LOH), Path OverHead (POH) and Virtual Tributary Path OverHead (VT POH).
Figure 7 – SOH Section Overhead
Figure 8 – LOH Line Overhead