A Cost Effective Architecture and Throughput Efficient Dynamic Bandwidth Allocation Protocol for Fog Computing Over EPON
Dibbendu Roy, Sourav Dutta, Arunashish Datta, Goutam Das
Abstract
Edge and fog networks call for high speed and energy-efficient networking platforms. Passive Optical Networks (PON) have been identified as a promising candidate for such platforms. In conventional dynamic bandwidth allocation (DBA) schemes for PON, the transmitter of an optical network unit (ONU) remains idle until the completion of upstream transmission of all other ONUs which indicates poor utilization of the transmitter. Scheduling fog services during these free intervals of time would lead to improved transmitter utilization. In this work, we exploit this opportunity and present a DBA protocol and its architecture, for enabling fog services. Our architecture employs a single line card at the ONUs providing considerable savings in terms of cost and energy. The results show that the cost per ONU could be reduced by 87$ and power savings of 5W per ONU could be achieved compared to proposals using separate transceivers at the ONU. The proposed DBA improves the load tolerance by ~300% towards maintaining delay bound of 10 ms and an improvement in throughput by ~20% at high loads when compared to existing philosophies, which is highly desirable for a delay-sensitive fog network. Placing fog node at remote node allows the fog node to operate at higher loads while maintaining delay bound when compared to its placement at OLT.