Abstract: An optical network system for controlling a passive optical network (PON) in which at least one symmetric optical subscriber terminal and at least one asymmetric optical subscriber terminal coexist is provided.

Abstract: Disclosed are a method and system for determining and controlling power of an optical transmitter of an optical network unit (ONU) for a time and wavelength division multiplexing passive optical network (TWDM-PON). The system includes an RSSI collector configured to collect received signal strength indication (RSSI) information from upstream optical signals received from the ONUs connected to optical line terminal (OLT) ports, an ONU power level determiner configured to gather the pieces of RSSI information about the ONUs from the RSSI collector, and to determine power of optical transmitters of the ONUs based on the gathered information, and a power mode controller configured to receive power mode setting information of the optical transmitters of the ONUs from the ONU power level determiner, and to generate a physical layer operation and maintenance (PLOAM) message to control power modes of the ONUs based on the received power mode setting information.

Abstract: A Passive Optical Network (PON)-based system and method for providing handover between Optical Network Terminals (ONTs) are provided. The PON-based system may include an Optical Line Terminal (OLT), and an ONT to relay communication between the OLT and a mobile terminal. When the mobile terminal is connected to the ONT, the ONT may transmit a WiFi location update alarm message to the OLT, and the OLT may update a Look-Up Table (LUT) in response to the WiFi location update alarm message.

Abstract: A fast protection switching method for a Passive Optical Network (PON). When performing protection switching from an operation link (an operation network) to a protection link (a protection network) in a PON, the fast protection switching method enables rapidly updating Equalization Delay (EqD) values, even if the EqD values are different for Optical Network Terminals (ONTs) of varying distances.

Abstract: Disclosed herein is an apparatus and method for detecting an optical line fault in a Passive Optical Network (PON). The apparatus includes an optical distribution unit configured to, when a multiplexed signal of a downstream light signal and a monitoring light signal is input, distribute the multiplexed signal to an Optical Network Unit (ONU) of a first optical path and to a second optical path. An optical layer management unit is installed in the second optical path and is configured to set a time at which the monitoring light signal of the multiplexed signal provided to the second optical path is received to a starting time of monitoring light measurement, compare a monitoring light signal reflected and returned from the ONU with a signal pattern obtained when no fault occurs, and then determine whether a fault has occurred in a distribution network.

Abstract: Disclosed are an apparatus and a method capable of adjusting an upstream band for a corresponding ONU by detecting a quantity of bands occupied by a packet, not an effective user packet, among upstream transmission bands for each target object of allocation of each band in the OLT to examine whether a queue report is normal, and detecting an ONU, which transmits an abnormal queue report, according to the examination. An OLT of a PON according to an exemplary embodiment of the present disclosure includes: a frame monitoring unit configured to monitor upstream frame data received for each T-CONT; an error detection unit configured to determine whether a queue report error is generated for each T-CONT according to a result of the monitoring; and a band allocation controller configured to allocate an upstream band for an ONU, in which the queue report error is generated, separately from a normal ONU.

Abstract: Disclosed herein is an Intrusion Detection System (IDS) false positive detection apparatus and method. An IDS false positive detection apparatus includes a payload extraction unit for extracting payloads by dividing each packet corresponding to an IDS detection rule into a header and a payload. A false positive payload information generation unit generates false positive payload information required to identify a false positive payload by extracting a payload of a false positive packet based on results of packet analysis received from a manager. A false positive payload determination unit transmits results of a determination of whether each payload extracted by the payload extraction unit corresponds to a false positive payload, based on the false positive payload information, to the manager.

Abstract: An apparatus and method for detecting forgery/falsification of a homepage. The apparatus includes a homepage image shot generation module for generating homepage image shots of an entire screen of an accessed homepage. A character string extraction module extracts character strings from each homepage image shot using an OCR technique. A character string comparison module compares each of the extracted character strings with character strings required for determination of homepage forgery/falsification, thus determining whether the extracted character string is a normal character string or a falsified character string. A homepage falsification determination module determines whether the corresponding homepage has been forged/falsified, based on results of the comparison. A character string learning module learns the character string extracted from the homepage image shot, based on results of the determination, and classifies the character string as the normal character string or the falsified character string.

Abstract: Provided is a method of saving power in a passive optical network (PON) system including an optical line terminal (OLT) and a plurality of optical network units (ONUs), the OLT including an optical transceiver to communicate with at least one ONU through an optical line, and a controller to control the optical transceiver to transmit an upstream bandwidth map to the ONU at a predetermined transmission interval, wherein the transmission interval is determined based on a desired upstream data service delay time.

Abstract: Provided is an optical line terminator (OLT) to recover packet data and a clock from an optical signal including a silent interval. The OLT may receive packet data and a clock from at least one optical network unit (ONU). Even in a silent interval in which the at least one ONU does not transmit packet data, the OLT may successfully recover the clock.

Abstract: An apparatus and method for monitoring an optical line is provided. The optical line monitoring apparatus may include a comparison unit to extract first identification information about an optical network terminal (ONT) from reflected data that is reflected and received from the optical line, and to compare the extracted first identification information to predetermined second identification information about the ONT, and a processor to analyze a state of the optical line using the reflected data when the first identification information is identical to the second identification information.

Abstract: The inventive concept relates to an optical line terminal registering optical network terminals having overlapping serial numbers. The optical line terminal may include a memory storing serial number information of optical network terminals of which a registration is completed in a storage region; and a control part that if a serial number by a serial number request is received from optical network terminals, the received serial number is compared with the serial number information of the memory and if they overlap each other, a previously set preliminary identifier is allocated to the optical network terminal having an overlapping serial number.

Abstract: An indexing apparatus and method for search of security monitoring data are provided. The indexing apparatus includes a data collection unit and a data index generation unit. The data collection unit collects data, that is, a basis of search of monitoring information, from a database in which security monitoring data has been stored. The data index generation unit generates file structure-based data in which indices have assigned to multiple search elements of the data collected by the data collection unit.

Abstract: Disclosed is a method of registering only an authorized optical network terminal among a plurality of optical network terminals with the same serial number, in an optical line terminal, using a public key encryption algorithm, in a Gigabit Passive Optical Network (GPON). According to an exemplary aspect, a GPON system encrypts a physical layer OAM message transmitted/received for serial number registration of an optical network terminal, using a key distributed according to a public key encryption algorithm, and authenticates registration of the optical network terminal using the encrypted physical layer OAM message. Accordingly, it is possible to securely authenticate registration of an authorized optical network terminal and block registration of unauthorized optical network terminals.

Abstract: An apparatus and method for managing a dynamic bandwidth allocation to support a low-power mode, in a passive optical network (PON) are provided. The apparatus may include a power saving mode managing unit to manage a power saving mode of at least one optical network unit (ONU), a bandwidth allocation parameter storage unit to store a bandwidth allocation parameter used for a power saving mode, and to maintain the stored bandwidth allocation parameter, and a dynamic bandwidth allocating unit to provide bandwidth allocation information to the at least one ONU, when the stored bandwidth allocation parameter is received.

Abstract: An optical subscriber network for power reduction is provided. The optical subscriber network may include an Optical Line Terminal (OLT) and an Optical Network Terminal (ONT). The OLT may manage a plurality of ONTs by classifying the plurality of ONTs into a sleep group, and may multicast a sleep allowance message only to ONTs included in a predetermined sleep group.

Abstract: Provided is an optical network unit saving power. The optical network unit may include a processor checking whether at least one downward physical block, the upward physical block and a data switching block operate in an idle mode, sequentially transiting at least one downward physical block, an upward physical block and a data switching block to a sleep mode according to the checking result and sequentially transiting an optical transmission-reception block and the medium access control block to a sleep mode by judging whether or not a medium access control block transits to a sleep mode.

Abstract: Provided is an OLT including a wavelength splitter that splits all upstream optical signals with different wavelengths received from at least one ONU according to wavelength, at least one receiver that receive the optical signals split by the wavelength splitter according to wavelength, a wavelength selector that allocates an upstream transmission wavelength of the at least one ONU, and a transmitter that transmits wavelength allocation information allocated by the wavelength selector to the at least one ONU.

Abstract: A method and apparatus of detecting a rogue optical network unit (ONU) is provided. An optical line terminal (OLT) detects an abnormal upstream transmission to determine a plurality of rogue ONU candidates, and transmits a sleep allow message instructing a transition to a sleep mode to each of the plurality of rogue ONU candidates. The OLT detects the rogue ONU among the plurality of rogue ONU candidates based on upstream transmissions from the plurality of rogue ONU candidates in the sleep mode. Since the detection of the rogue ONU is performed in the sleep mode, the remaining ONUs can transition from the sleep mode to the normal mode after the detection of the rogue ONU is completed, thereby making it possible to rapidly resume upstream communication.

Abstract: A dynamic bandwidth allocation apparatus of a passive optical network detects guarantee agreement information of each transmission container (T-CONT) queue of at least one optical network unit (ONU) that is connected to the dynamic bandwidth allocation apparatus in order to dynamically allocate a bandwidth is provided. The dynamic bandwidth allocation apparatus sets a queue threshold according to a buffer size of each T-CONT queue of at least one ONU, and calculates a service level agreement (SLA) parameter of at least one ONU using guarantee agreement information and a queue threshold. The dynamic bandwidth allocation apparatus allocates a bandwidth for every frame of each ONU using each SLA parameter of at least one ONU.