摘要:
One embodiment provides a media access control (MAC) module facilitating operations of an Ethernet passive optical network (EPON). The MAC module includes a frame formatter configured to generate a MAC control frame. The generated MAC control frame includes at least one of: an organizationally unique identifier (OUI) field, an OUI-specific operation code (opcode) field, and a number of fields associated with the OUI-specific opcode. Transmission of the MAC control frame facilitates realization of an EPON function based on the fields associated with the OUI-specific opcode.
摘要:
One embodiment provides a media access control (MAC) module facilitating operations of an Ethernet passive optical network (EPON). The MAC module includes a frame formatter configured to generate a MAC control frame. The generated MAC control frame includes at least one of: an organizationally unique identifier (OUI) field, an OUI-specific operation code (opcode) field, and a number of fields associated with the OUI-specific opcode. Transmission of the MAC control frame facilitates realization of an EPON function based on the fields associated with the OUI-specific opcode.
摘要:
One embodiment of the present invention provides a method for facilitating asymmetric line rates in an Ethernet passive optical network (EPON) which includes a central node and at least one remote node. During operation, the system provides a downstream code-group clock, wherein each cycle thereof corresponds to a code group transmitted from the central node to a remote node. The system also provides an upstream code-group clock, wherein each cycle thereof corresponds to a code group received at the central node from a remote node. In addition, the system provides a multi-point control protocol (MPCP) clock, wherein the frequency ratio of the MPCP clock to the downstream code-group clock is different from the frequency ratio of the MPCP clock to the upstream code-group clock, thereby allowing the downstream transmission to be performed at a faster line rate than the upstream transmission line rate.
摘要:
One embodiment of the present invention provides a system that decrypts downstream data in an Ethernet passive optical network (EPON). During operation, the system receives a data frame which is encrypted based on a remote input block and a session key, wherein the remote input block is constructed based on a remote cipher counter and a remote block counter. The system adjusts a local cipher counter based on a received checksum located in a preamble of the data frame, wherein the local cipher counter is substantially synchronized with the remote cipher counter. In addition, the system truncates the local cipher counter by discarding n least significant bits thereof. The system then constructs a local input block based on the truncated cipher counter and a local block counter for the received data frame. Next, the system decrypts the data frame based on the local input block and the session key.
摘要:
One embodiment of the present invention provides a system that facilitates forwarding of packets in an Ethernet passive optical network (EPON), which includes a central node and at least one remote node. During operation, the system assigns a logical link identifier (LLID) to a remote node, wherein an LLID corresponds to a logical link between the central node and a remote node. The system also associates an LLID with a port of a switch within the central node, wherein the switch has a number of ports; wherein a port may be a physical port or a virtual port; and wherein the number of ports on the switch are divided into network-side ports and user-side ports. Upon receiving a downstream packet from a network-side port, the system searches a mapping table to determine whether one or more field values of the downstream packet correspond to any LLIDs or ports. If the one or more field values correspond to an LLID, the system assigns the LLID to the downstream packet and transmits the downstream packet to a remote node.
摘要:
One embodiment provides a system that performs protection switching in an Ethernet passive optical network (EPON), which includes an optical line terminal (OLT) and at least one optical network unit (ONU). The system is configured with at least one redundant component for the OLT and/or ONUs, wherein the redundant component can be optical or electrical, and can be a port, line card or link. The system provides protection by detecting a failure, and switching automatically to the redundant components to reduce service disruption time. The protection switching comprises: preserving the existing configuration over the loss of at least one of a multiple-point control protocol (MPCP) message; an operations, administration and maintenance (OAM) message; and a signal on the physical layer. The system recovers from the failure without performing ONU discovery.
摘要:
One embodiment provides a system that performs protection switching in an Ethernet passive optical network (EPON), which includes an optical line terminal (OLT) and at least one optical network unit (ONU). The system is configured with at least one redundant component for the OLT and/or ONUs, wherein the redundant component can be optical or electrical, and can be a port, line card or link. The system provides protection by detecting a failure, and switching automatically to the redundant components to reduce service disruption time. The protection switching comprises: preserving the existing configuration over the loss of at least one of a multiple-point control protocol (MPCP) message; an operations, administration and maintenance (OAM) message; and a signal on the physical layer. The system recovers from the failure without performing ONU discovery.
摘要:
One embodiment of the present invention provides a system for forwarding packets in an Ethernet passive optical network (EPON) which includes a central node and at least one remote node. During operation, the system associates a logical link identifier (LLID) to a logical link between the central node and a remote node, wherein the logical link corresponds to a priority level based on a certain service level agreement (SLA). After receiving a packet to be forwarded to a remote node, the system then determines the value of one or more fields within the packet which is used to indicate a priority level for the packet. Subsequently, the system assigns an LLID to the packet based on the value of the one or more fields, thereby facilitating differentiated service qualities within the EPON.
摘要:
One embodiment of the present invention provides a system that facilitates registration of remote nodes in an Ethernet passive optical network (EPON). The system includes a central node and at least one remote node, wherein a number of virtual remote nodes are coupled to a common physical remote node and transmit upstream data through a common transmitter within the common physical remote node. During an initial discovery cycle, the system receives a solicitation message from the central node at a remote node, wherein the solicitation message assigns a discovery slot in which an unregistered remote node may transmit a response message to the central node for registration. The system then transmits a response message from an unregistered remote node to register within the assigned discovery slot. If multiple virtual remote nodes coupled to the common physical remote node seek registration concurrently, the system controls the transmission of response messages from these virtual remote nodes to the central node so as to avoid collisions between response messages from different remote nodes.