A heuristic approach for designing hybrid PONs employing WDM and OCDMA with asymmetric traffic distribution

In this paper we examine the resource provisioning aspects in a passive optical network (PON) employing wavelength-division multiplexing (WDM) and optical code-division multiple access (OCDMA) techniques. A judicious resource allocation scheme is proposed for a given set of optical codes and wavelengths with due consideration to the traffic asymmetry between upstream and downstream transmissions. The proposed scheme employs some initial heuristic estimates, followed by a subsequent open search mode towards reaching an optimal solution. The search mechanism in the provisioning scheme is carried out by employing some network performance metrics and evaluated using the appropriate analytical models.