Inverse-multiplexing in multi-layer optical grooming networks

Optical DWDM technology has delivered immense scalability across long-haul and metropolitan core networks. However, since many client services still operate at slower speeds, there remains a large "granularity gap" with larger multi-gigabit wavelengths. Hence, various sub-rate grooming technologies have been developed to efficiently multiplex smaller demands on wavelengths and improve utilizations. The most notable such offering is "next-generation" SONET/SDH, which is now gaining significant market traction. A key feature of NGS is inverse multiplexing, which can resolve demands into smaller "subconnections." However, most studies on sub-rate grooming have not fully leveraged this vital addition. This paper presents a detailed initial look at inverse multiplexing in SONET/SDH-DWDM networks. Here, a novel grooming algorithm is tabled and its detailed performance is studied. Overall, results indicate notable improvements via the inverse multiplexing capability.