An efficient multi-OLT and multi wavelengths passive optical network for differentiated classes of services

Passive optical network (PON) is getting more popularity because it provides large bandwidth, uses only passive components that requires less power consumption, highly dynamic access network, and effectively converges several service providers. With the increase of multiple users having different priority classes of services an efficient access network is required which can handle the different data classes with better quality of services (QoSs). Usually, a single optical line terminal (OLT) and single wavelength (SS) PON is capable to provide multiple services and applications such as IPTV, HDTV, video conferencing, and real-time data transmission. However, the SS-PON is not the best network architecture to maintain better QoSs for all those services because it requires a complex dynamic bandwidth allocation (DBA) algorithm and synchronization of local time those lead a large delay. To overcome those problems in SS-PON, in this paper, we propose an efficient PON architecture which consists of two OLTs and two uplink wavelengths, i.e., multi-OLT and multi-wavelengths PON (MM-PON), for different classes of services. Here, two OLTs are used to reduce the data processing complexity and two uplink wavelengths are used to transmit the three different priority classes of services defined by IEEE802.1D standard. This paper presents a new network structure of MM-PON with simulation results for modified limited service DBA algorithm to prove the validity of the proposed network architecture. The simulation results show that the MM-PON with strict priority scheduling provide less packet delay, reduce the probability of packet loss, remove light load penalty, and maintain service level agreements for each priority class of service than the conventional SS-PON.