Patent ID: 7286538
Filing Date: 2007-10-23
Classification: H04L,H04Q

Abstract:
1. A method for checking whether a transmission is a multicast transmission or not in an Ethernet passive optical network including an Optical Line Termination (OLT) and multiple Optical Network Units (ONUs) connected to the OLT by generating a multicast logical link ID (LLID) that represents multicast information, from a multicast Medium Access Control (MAC) address in a MAC layer in one of the multiple ONUs or the OLT, so that at least one ONU from among the multiple ONUs or the OLT receives the multicast transmission, the method comprising the steps of: (a) modifying the multicast MAC address and mapping the modified address to an LLID field in a Regenerator Section (RS) layer below the MAC layer; and (b) generating mode information that represents a multicast transmission, and arranging the mode information in a position adjacent to the LLID field, wherein, the RS layer checks whether a transmission transmitted to the said at least one ONU selected from among the multiple ONUs or the OLT is a multicast transmission or not.