Abstract: A method of distributing group identifiers IDs (GIDs) in a power line communication (PLC) network, a method of receiving the GIDs, an authentication apparatus, and a PLC apparatus are provided. The authentication apparatus includes: an authentication mode storing unit which stores an authentication mode having a value including one of an authentication authorized mode and an authentication unauthorized mode; a GID request receiver which receives a GID request message from a PLC apparatus; and a GID transmitter which, if the authentication mode is the authentication authorized mode, transmits a GID corresponding to the PLC apparatus to the PLC apparatus. Authentication is realized in a PLC media access control layer distributing the GIDs between a PLC apparatus and an authentication apparatus, so manually inputting a GID into the PLC apparatus is not necessary. Further, the GIDs are distributed via the authentication apparatus, thereby centrally managing the GIDs.

Abstract: A method and apparatus to efficiently transmit data. The method and apparatus effectively aggregate data and transmit the data in a high-speed power line communication (PLC) network. The method of transmitting the data includes combining each of at least one or more data units transferred from an upper layer, with a field to indicate attribute information of the data unit, dividing the combined data units and fields into frame blocks of an identical size, and aggregating the divided frame blocks and transferring the aggregated frame blocks as one frame to a PHY layer. In this way, data units of a variety of types and sizes transferred from the upper layer are aggregated and transmitted as the one frame.

Abstract: A method of transmitting data more effectively, and more particularly, a method of classifying service traffic, transmitting data according to the classifications of the service traffic, and performing a contention free slot (CFS) allocation in order to transmit data in a power line communication (PLC) network, and an apparatus to do the same. The data transmission method includes determining transmission priority of data according to service traffic characteristics, and transmitting data according to the determined transmission priority, thereby providing differentiated quality of service (QoS) according to service traffic characteristics.

Abstract: An apparatus and method of streaming content by adaptively selecting a peer-to-peer (P2P) method or a server-client method according to a network environment, and a computer readable medium having recorded thereon a program for executing the method are provided. The apparatus includes middleware which supports the P2P method, middleware which supports the server-client method, an adaptation manager which provides a list of content, determines one of at least one node and at least one server sharing content which is selected as a source device according to a content sharing method and their available bandwidths, and determines a content sharing method used by the source device as a streaming method, and an application unit which controls the selected content to be received from the source device by using middleware and a transfer layer corresponding to the determined streaming method, and the received content to be reproduced.

Abstract: A method of joining a cell by using a proxy coordinator. The method of joining a cell by using a proxy coordinator includes requesting a second device to operate as a proxy coordinator from a first device positioned out of a beacon frame reachable area of the cell, transmitting a time period to operate as the proxy coordinator allocated by a coordinator of the cell, informing the first device that the second device can operate as the proxy coordinator, transmitting a cell join request to the proxy coordinator from the first device through the second device, and transmitting a beacon frame including time allocation information from the coordinator to the first device through the second device.

Abstract: A method of transmitting data more effectively, and more particularly, a method of transmitting data to a group comprising a plurality of reception stations that receive the same data from a transmission station when the stations communicate the data in a power line communication (PLC) network, and an apparatus to do the same. According to the method, a transmission station transmits data to a group including a plurality of reception stations that receive the same data at a time, to prevent a channel bandwidth from being wasted, and to prevent a station that does not desire to receive the data from receiving the data.

Abstract: A method and apparatus for packet aggregation in a power line communication network (PLC) are provided. The method of aggregating packets includes: by performing a PLC channel estimation, determining whether or not a channel condition is good; if the channel condition is good, determining whether or not the data desired to be transmitted is suitable for packet aggregation according to the type of data; and if the channel condition is good and the data desired to be transmitted is suitable for the packet aggregation, aggregating packets of the data desired to be transmitted. Since a decision on whether or not to aggregate packets is determined according to a channel condition at a physical level and the type of data at an application level, packet aggregation can be performed in appropriate response to the frequently changing condition of a channel and the characteristic of the data desired to be transmitted.

Abstract: Provided is an apparatus and method of displaying power line communication (PLC) channel information. The apparatus for displaying PLC channel information includes a channel information determining unit which performs channel estimation of a PLC channel, and, based on the channel estimation, determines channel information on the PLC channel including a bandwidth of the PLC channel which is available for a user in a PLC network; and a channel information displaying unit which displays the channel information to the user.

Abstract: A method of data communication between power line communication (PLC) stations belonging to different PLC cells includes transmitting a station ID of a PLC reception station to a PLC cell bridge (CB) of a first PLC cell to which a PLC transmission station belongs, receiving a group identification (GID) and an encryption key of a second PLC cell to which the PLC reception station belongs from the PLC CB of the first PLC cell, encrypting data to be transmitted using the encryption key of the second PLC cell, and transmitting the station ID of the PLC reception station, the GID of the second PLC cell, and the encrypted data, to the PLC CB of the first PLC cell, and an apparatus to perform the method.

Abstract: A method and apparatus for packet aggregation in a power line communication network (PLC) are provided. The method of aggregating packets includes: by performing a PLC channel estimation, determining whether or not a channel condition is good; if the channel condition is good, determining whether or not the data desired to be transmitted is suitable for packet aggregation according to the type of data; and if the channel condition is good and the data desired to be transmitted is suitable for the packet aggregation, aggregating packets of the data desired to be transmitted. Since a decision on whether or not to aggregate packets is determined according to a channel condition at a physical level and the type of data at an application level, packet aggregation can be performed in appropriate response to the frequently changing condition of a channel and the characteristic of the data desired to be transmitted.

Abstract: A bit rate control method and apparatus for MPEG-4 video coding are provided.

Abstract: A method and apparatus to efficiently transmit data. The method and apparatus effectively aggregate data and transmit the data in a high-speed power line communication (PLC) network. The method of transmitting the data includes combining each of at least one or more data units transferred from an upper layer, with a field to indicate attribute information of the data unit, dividing the combined data units and fields into frame blocks of an identical size, and aggregating the divided frame blocks and transferring the aggregated frame blocks as one frame to a PHY layer. In this way, data units of a variety of types and sizes transferred from the upper layer are aggregated and transmitted as the one frame.

Abstract: A method of distributing group identifiers IDs (GIDs) in a power line communication (PLC) network, a method of receiving the GIDs, an authentication apparatus, and a PLC apparatus are provided. The authentication apparatus includes: an authentication mode storing unit which stores an authentication mode having a value including one of an authentication authorized mode and an authentication unauthorized mode; a GID request receiver which receives a GID request message from a PLC apparatus; and a GID transmitter which, if the authentication mode is the authentication authorized mode, transmits a GID corresponding to the PLC apparatus to the PLC apparatus. Authentication is realized in a PLC media access control layer distributing the GIDs between a PLC apparatus and an authentication apparatus, so manually inputting a GID into the PLC apparatus is not necessary. Further, the GIDs are distributed via the authentication apparatus, thereby centrally managing the GIDs.

Abstract: A method of joining a cell by using a proxy coordinator. The method of joining a cell by using a proxy coordinator includes requesting a second device to operate as a proxy coordinator from a first device positioned out of a beacon frame reachable area of the cell, transmitting a time period to operate as the proxy coordinator allocated by a coordinator of the cell, informing the first device that the second device can operate as the proxy coordinator, transmitting a cell join request to the proxy coordinator from the first device through the second device, and transmitting a beacon frame including time allocation information from the coordinator to the first device through the second device.

Abstract: An apparatus and method of streaming content by adaptively selecting a peer-to-peer (P2P) method or a server-client method according to a network environment, and a computer readable medium having recorded thereon a program for executing the method are provided. The apparatus includes middleware which supports the P2P method, middleware which supports the server-client method, an adaptation manager which provides a list of content, determines one of at least one node and at least one server sharing content which is selected as a source device according to a content sharing method and their available bandwidths, and determines a content sharing method used by the source device as a streaming method, and an application unit which controls the selected content to be received from the source device by using middleware and a transfer layer corresponding to the determined streaming method, and the received content to be reproduced.

Abstract: A method of transmitting data more effectively, and more particularly, a method of classifying service traffic, transmitting data according to the classifications of the service traffic, and performing a contention free slot (CFS) allocation in order to transmit data in a power line communication (PLC) network, and an apparatus to do the same. The data transmission method includes determining transmission priority of data according to service traffic characteristics, and transmitting data according to the determined transmission priority, thereby providing differentiated quality of service (QoS) according to service traffic characteristics.

Abstract: A method of transmitting data more effectively, and more particularly, a method of transmitting data to a group comprising a plurality of reception stations that receive the same data from a transmission station when the stations communicate the data in a power line communication (PLC) network, and an apparatus to do the same. According to the method, a transmission station transmits data to a group including a plurality of reception stations that receive the same data at a time, to prevent a channel bandwidth from being wasted, and to prevent a station that does not desire to receive the data from receiving the data.

Abstract: A method of data communication between power line communication (PLC) stations belonging to different PLC cells includes transmitting a station ID of a PLC reception station to a PLC cell bridge (CB) of a first PLC cell to which a PLC transmission station belongs, receiving a group identification (GID) and an encryption key of a second PLC cell to which the PLC reception station belongs from the PLC CB of the first PLC cell, encrypting data to be transmitted using the encryption key of the second PLC cell, and transmitting the station ID of the PLC reception station, the GID of the second PLC cell, and the encrypted data, to the PLC CB of the first PLC cell, and an apparatus to perform the method.

Abstract: Provided is an apparatus and method of displaying power line communication channel information. The apparatus for displaying power line communication (PLC) channel information includes a channel information determining unit which performs PLC channel estimation and determines channel information including a bandwidth which is available for a user in a power line communication network; and a channel information displaying unit which displays the channel information to the user. Since channel information is determined through channel estimation and displayed to a user, it is possible to easily check whether a channel can be used before installing a power line communication (PLC) device. In an application, information on kinds of a service which can be selected by the user or expected quality of the service can be previously checked.

Abstract: Provided is an apparatus for adjusting the phase difference between different phases in a power line communication (PLC) system. The apparatus includes a power signal blocking unit blocking a power signal and allowing a data signal to pass between two different phases on three-phase power lines; and a data signal delaying unit delaying the data signal by the phase difference between the two different phases. Accordingly, it is possible to prevent data collision and a time delay in data transmission between different phases by employing the phase adjusting apparatus in a PLC system, thereby improving the performance of PLC.