OC-96/OC-192 technology impact on SONET self-healing rings

The SONET self-healing ring architecture is planned for interoffice network deployment starting from 1992. Unfortunately, the demand requirement for metropolitan intraLATA interoffice networks could exhaust the OC-48 (2.5 Gbit/s) ring capacity, where OC-48 is the maximum rate that has been defined in current SONET standards. This could result in LATA interoffice networks composed of many small SONET rings interconnected at hub buildings. The use of ultrahigh-speed add-drop multiplexers (ADMs) operating at OC-96 (4.8 Gbit/s) or OC-192 (9.6 Gbit/s) rates can maximize the potential cost and survivability advantages of SONET rings by connecting more office buildings on a ring, thus simplifying operations and planning by reducing the number of interconnections needed at hub buildings. The OC-192 fiber transmission rate has been demonstrated in research laboratories.