Dynamic bandwidth and wavelength allocation with coexistence of transmission technologies in TWDM PONs

In a Passive Optical Network (PON), the possibility of smooth upgrading the network infrastructure is an important requirement for network providers as it allows to minimize initial investments for networks deployment. During the upgrade process, it is expected a coexistence of new and old end-users, i.e., Optical Network Units (ONU), with diverse transceiver technologies. Our work focuses on the scenario where the network is upgraded from a TDM PON to a hybrid WDM/TDM PON (both short-reach and long-reach), and where the transceivers used in the old TDM PON can coexist with the new transceivers adopted in the hybrid WDM/TDM PON. In this work, we propose new Dynamic Bandwidth and Wavelength Allocation (DBWA) algorithms that solve the problem of managing the traffic originated by end-user transceivers with different characteristics. Specifically, in this paper we focus on the case of transceivers characterized by different tuning time. To investigate the importance of a DBWA which can specifically manage the traffic originated by transceivers with different tuning time, we also compare them to DBWAs which are not aware that different transmission technologies with different requirements coexist in the network. Finally, we test these DBWAs in different network scenarios (e.g., short-reach (PON) and long-reach (LR-PON) scenarios), and discuss what are the network parameters that mostly affect the algorithms performance.