Design and Implementation of an EPON Master Bridge Function in an ASIC

An EPON(Ethernet Passive Optical Network) master, slave chipset was developed. In EPON, LLID(Logical Link ID) value in the Ethernet frame’s preamble is used to make the PON look like a point-topoint links seen from the OLT(Optical Line Termination) and ONUs. This paper describes the functions and implementation of an EPON bridge in the master chip which performs bridge function for the upper network port and many lower PON logical ports differentiated by LLID. This bridge also has VLAN(Virtual LAN)-LLID mapping function to make the PON appear as many VLANs seen from the network port. It is also possible to define many VLANs for each ONU. It also has multicast pruning function through which only registered multicast traffic is sent downstream to destined ONUs.