Abstract: A radio-over-fiber (RoF) system and method for controlling a transmission time is provided. In a Time Division Duplex (TDD) wireless communication system comprising a Base Station (BS) having a donor and a remote connected thereto via am optical fiber, upstream and downstream Radio Frequency (RF) signals are transmitted and received, and by reliably transmitting a switch control signal to the remote and simultaneously compensating for a transmission time delay occurring in the optical cable, time synchronization of the upstream and downstream RF signals transmitted and received via antennas of the BS and the remote is controlled, thereby efficiently increasing the performance of a TDD wireless service system.

Abstract: A broadcast/communication convergence system, and an FTTH (Fiber To The Home) system that can accommodate broadcast signals of various channels and variable band signals by converging broadcast and communication signals and transmitting the converged broadcast and communication signals using an IEEE 1394 transmission method serving as a standard interface in the FTTH system for broadcast/communication convergence. An OLT (Optical Line Terminal) transfers a plurality of broadcast signals and a communication signal received from external broadcast and communication providers through a single optical signal (A).

Abstract: A method of treating a handover in a bridge-based radio access station backbone network including a plurality of base station bridges each including a two-tiered switch connected with a plurality of radio access stations, a plurality of SCBs (Site Core Bridges) each composed of two-tiered switch for constituting the core network, and an HLR (Home Location Register) for managing the structural information of the network constituents. The SCB stores the terminal information containing the receiving address of the initial terminal registration message and the SCB to delete the terminal information in response to a disconnection message of the terminal caused by handover, to request the SCBs in the terminal end of the old MAC-in-MAC tunnel to delete the tunnel information and the terminal information, and to inform the HLR of initiating the handover to change the registered operational state of the terminal.

Abstract: A method and apparatus for ensuring QoS in a synchronous Ethernet bridge are disclosed, in which a classifier classifies an ingress packet according to a PHB mapped to a DSCP value of the packet and provides the classified packet to one of a predetermined synchronous packet queue and a predetermined asynchronous packet queue, a buffer queue with a plurality of queues mapped to priority levels buffers the classified packet, a marker marks the buffered packet as a synchronous packet or, if the buffered packet is an asynchronous packet, marks the packet in a predetermined format corresponding to a priority level of the packet, and a synchronous Ethernet scheduler schedules the marked packet.

Abstract: A method of treating signals in a bridge-based radio access station backbone network including a plurality of base station bridges (BSBs), with each BSB having a 2-tiered switch connected with a plurality of radio access stations. A plurality of SCBs (Site Core Bridges), each of having a 2-tiered switch for constituting the core network, includes the steps of buffering by the SCB a predetermined number of previously-transmitted frames when operating as a crossover bridge, and causing the SCB to retransmit selected ones of the buffered previously-transmitted frames to a terminal in response to a handover completion signal.

Abstract: A bridge-based RAS backbone network system and a signal processing method therefor are provided. In the bridge-based RAS backbone network system, a plurality of BSBs with Layer 2 (L2) switches are connected to a plurality of RASs, anda plurality of SCBs with L2 switches are connected to part of the BSBs in a lower layer, forming a core network. An HLR manages configuration information of network entities by storing the IP addresses and MAC addresses of MNs within the network and the addresses of SCBs to which the MNs belong in a table. Each of the SCBs statically preserves the MAC address of an external default router, for relaying an egress frame, statically registers its individual MAC address in other SCBs in the core network beforehand, detects a destination MN through the HLR, and sends a frame to the SCB of the destination MN or the MAC address of the external default router.

Abstract: Disclosed is a bridged portable internet system, which includes: a plurality of edge bridges entirely connected as a mesh structure to form a core network, and configured as a layer 2 switch; a plurality of Radio Access Stations (RASs) connected to one of the plurality of edge bridges to provide portable internet services to Mobile Nodes (MNs) within the range of services; and a Neighbor Discovery Server (NDS) for supporting neighbor discovery of components in the network and storing and managing configuration information of the components, wherein each of the plurality of edge bridges maintains an optimal path through a predetermined routing protocol, identifies the destination of a Media Access Control (MAC) frame transmitted by an MN connected to an edge bridge itself through a corresponding RAS by referring to the configuration information from the NDS so as to transmit a corresponding MAC frame to the MAC address of an edge bridge to which a corresponding CN is connected by performing MAC in MAC encapsul

Abstract: A method for time synchronization in a distributed control system includes the steps of: when a sync is received from a master-side, confirming both a reception time point of the corresponding sync and a compensation time point of a previous frequency, and determining if a result obtained by confirming the two time points corresponds to a preset Frequency Compensation Interval (FCI); performing only a time offset compensation operation when the result obtained by confirming the two time points does not correspond to the preset FCI; and performing both time offset and frequency compensation operations when the result obtained by confirming the two time points corresponds to the preset FCI.

Abstract: Disclosed is a method, apparatus and computer-readable medium for selecting a root bridge when a spanning tree is configured in an Ethernet network including a plurality of legacy switches and a plurality of synchronous switches. The method comprises the steps of providing in advance identification information in a configuration BPDU message of the synchronous switch, the identification information representing that a corresponding switch is an AV switch, broadcasting configuration BPDU messages by the legacy switches and the synchronous switches; and receiving configuration BPDU messages by the synchronous switch from other switches, confirming bridge priorities according to the synchronous switches through the received configuration BPDU message and the identification information to select a synchronous root bridge, receiving configuration BPDU messages by the legacy switch from other switches, and confirming bridge priorities through the received configuration BPDU messages to select a legacy root bridge.

Abstract: Disclosed is a method for approval of a time-dependent stream input to a predetermined node in a residential Ethernet system, the method including the steps of receiving a transmission request of the time-dependent stream by the predetermined node, extracting a pacing parameter and a cycle number, which are a delay value of the predetermined node and a transmission period of the time-dependent stream, respectively, from the transmission-requested time-dependent stream, calculating a transmission bandwidth of an entire time-dependent stream to be transmitted through the predetermined node, by taking into consideration the pacing parameter and the cycle number, determining if the transmission bandwidth, which includes the transmission-requested time-dependent stream, satisfies a total transmission bandwidth based on the pacing parameter and the cycle number and determining whether to approve the transmission-requested time-dependent stream.

Abstract: A residential Ethernet node device for transmitting synchronous data uses a counter in a residential Ethernet system. The device includes a parser for receiving residential Ethernet data from external other node devices, and parsing the received Ethernet data as synchronous data and asynchronous data. An asynchronous switch switches and transmits the parsed asynchronous data. A synchronous switch switches and transmits the parsed synchronous data. A multiplexer is connected with the asynchronous switch and the synchronous switch, and multiplexes the asynchronous and synchronous data. A synchronous data band assignment unit for, by the count of a counter, indicating synchronous data bandwidth information determined from a synchronous data bandwidth reservation process, and transmitting the indicated bandwidth information to the multiplexer, thereby determining a multiplex position for synchronous data transmission.

Abstract: A residential Ethernet switching device for sub frame-based switching in a residential Ethernet system is provided. The device includes a plurality of reception data path processors for parsing a residential Ethernet frame inputted to the residential Ethernet switching device, as respective residential Ethernet sub frames, and outputting the parsed residential Ethernet sub frames, a switch fabric for switching the residential Ethernet sub frames inputted through the plurality of reception data path processors, a plurality of transmission data path processors for providing an output path for multiplexing and outputting the residential Ethernet sub frames switched through the switch fabric, and a local cycle counter connected to the plurality of reception data path processors, the switch fabric, and the plurality of transmission data path processors, and providing cycle counter information on the respective residential Ethernet sub-frames.

Abstract: Disclosed is a time synchronization method for selecting a predetermined timing master and according Times of Day of a plurality of nodes with a Time of Day of the predetermined timing master in a Residential Ethernet system, which includes the nodes, the method comprising the steps of receiving, by a predetermined node among the nodes, a time value of the predetermined timing master, and setting a time value of the predetermined node as the received time value, and changing, by the predetermined node, the set time value by taking into consideration a data transmission delay time value between the predetermined node and the predetermined timing master.

Abstract: Disclosed is a Residential Ethernet node apparatus for maintaining a starting point of a superframe, the Residential Ethernet node apparatus comprising a synchronous queue for receiving and temporarily storing synchronous data, in order to transmit the synchronous data by inserting the synchronous data into a transmission cycle, a parser for receiving asynchronous frames from at least one exterior source, parsing the asynchronous frames according to characteristics of the asynchronous frames, a plurality of the asynchronous queues for separately storing the asynchronous frames received from the parser according to the characteristics of the asynchronous frames, a scheduler for receiving the asynchronous frames from the asynchronous queues, and transmitting the received asynchronous frame when it is possible to transmit the received asynchronous frame, and a multiplexer, which receives a synchronous frame from the synchronous queue and an asynchronous frame from the scheduler so as to transmit the synchronous

Abstract: Disclosed is a method of performing a periodical synchronization at a predetermined transmission link for ensuring a start of a super frame in a residential Ethernet system. The method includes the steps of ensuring a start of a first predetermined super frame at the predetermined transmission link, transmitting Sync frames and Async frames through a predetermined number (N-1) of super frames, in which N is a total number of the super frames, and controlling an Async frame to be transmitted at an end point of the (N-1) super frames in such a manner that a start of a next super frame (Nth super frame) is strictly ensured, thereby maintaining a synchronization for the start of the super frame.

Abstract: A Residential Ethernet switching apparatus for performing time slot switching includes an input unit for receiving frames as input, and a parser for parsing the received frames into asynchronous Ethernet frames (AsyncE frames) and Residential Ethernet frames (ResE frames). An AsyncE switching processor performs a switching operation for an AsyncE frame parsed by the parser. A ResE switching processor performs, according to positions of time slots included in a ResE frame parsed, a virtual MAC (VMAC) processing for the ResE frame The ResE switching processor also performs a switching operation based on a result of the VMAC processing. A multiplexer multiplexes the AsyncE frame switched by the AsyncE switching processor, and the ResE frame switched by the ResE switching processor, for output.

Abstract: A method for transmitting asynchronous data includes including: comparing a size of asynchronous data with that of an empty transmission area; inserting the asynchronous data into the empty transmission area when the asynchronous data has a size smaller than or equal to that of the empty transmission area; determining if the empty transmission area has a size larger than a predetermined threshold value when the asynchronous data has a size larger than that of the empty transmission area; transmitting the asynchronous data with the empty transmission area left when the empty transmission area has a size smaller than the predetermined threshold value; and segmenting the asynchronous data according to the size of the empty transmission area when the empty transmission area has a size larger than the predetermined threshold value, inserting the segmented asynchronous data into the empty transmission area, and transmitting remaining segmented asynchronous data in a subsequent transmission cycle.

Abstract: A method for generating a super frame of a predetermined size in a a residential Ethernet system for separately transmitting isochronous data and asynchronous data includes the steps of: receiving by the residential Ethernet system the isochronous data and the asynchronous data to be transmitted through the residential Ethernet system; dividing the received isochronous data into a plurality of sub-frames according to synchronous links; inserting an Ethernet header into each of the sub-frames, thereby generating a plurality of isochronous packets; and employing a remaining area, which is obtained by excepting an area of the isochronous packets from the predetermined size, as an asynchronous packet area, and inserting asynchronous packets including the asynchronous data into the asynchronous packet area.

Abstract: Disclosed is a method for forming a super frame used for transmitting isochronous data and asynchronous data in a residential Ethernet system. The method includes the steps of receiving the isochronous data and the asynchronous data to be transmitted through the residential Ethernet system, forming an isochronous frame using the received isochronous data, forming a cycle start frame used for reporting start of the super frame, and inserting the asynchronous data into an area of an asynchronous frame by employing a remaining area as the area of the asynchronous frame, the remaining area being obtained by excluding an isochronous frame area, which includes the cycle start frame and the isochronous frame, from an area having the predetermined size.

Abstract: A method for allocating slots for a synchronous Ethernet service in a Residential Ethernet system includes the steps of: receiving requests for synchronous Ethernet services from terminals requiring the synchronous Ethernet services; calculating a number of slots for each synchronous Ethernet service, and allocating slots for each terminal based on the calculated number of slots; transmitting information about the allocated slots through at least one Residential Ethernet switch; and receiving acknowledgement signals from the terminals in response to the allocated slot information and providing the synchronous Ethernet services using the allocated slots.