Abstract: An embodiment controller for use in a communication system for platooning vehicles that performs Vehicle-to-Vehicle (V2V) communication through controllers mounted in the platooning vehicles includes a communication unit configured to transmit and receive a message including control and sensor information of the platooning vehicles, a scheduler configured to store message transmission times of the platooning vehicles, and a determiner configured to determine whether a message received through the communication unit corresponds to schedule information stored in the scheduler, wherein the controller is configured to transmit a message in accordance with an order determined based on the schedule information and find out a message transmission order of the platooning vehicles by sharing the schedule information.

Abstract: An embodiment controller for use in a communication system for platooning vehicles that performs Vehicle-to-Vehicle (V2V) communication through controllers mounted in the platooning vehicles includes a communication unit configured to transmit and receive a message including control and sensor information of the platooning vehicles, a scheduler configured to store message transmission times of the platooning vehicles, and a determiner configured to determine whether a message received through the communication unit corresponds to schedule information stored in the scheduler, wherein the controller is configured to transmit a message in accordance with an order determined based on the schedule information and find out a message transmission order of the platooning vehicles by sharing the schedule information.

Abstract: Disclosed is a method of joint optimization of channel selection and frame scheduling for coexistence of LTE and WLAN in an unlicensed band, the method being performed by a baseband unit (BBU) pool and the method includes: selecting a component carrier (CC) having a highest idle probability by considering an idle probability of the CC for the unlicensed band; determining the number NI of idle subframes in the selected CC by considering a residence time in a WLAN system queue; and allocating a resource block (RB) to an LTE user terminal in a cell based on the number of selected CCs and the number of idle subframes and which appropriately selects a resource in a frequency domain and a time domain in LTE to acquire high throughput and fairness in the LTE and the WLAN in the unlicensed band.

Abstract: A method for configuring a service function path (SFP) for a software defined network (SDN) based service function chain (SFC) may comprise configuring a SFC which is a set of ordered service functions (SFs) by reflecting requirements of a flow flowing into a network; generating a primary SFP that is a path through which the flow is to be actually transmitted in the network according to the SFC; generating a secondary SFP against an error of the primary SFP; and controlling a transmission path through which the flow is transmitted to be at least one of the primary SFP and the secondary SFP.

Abstract: Disclosed is a method of joint optimization of channel selection and frame scheduling for coexistence of LTE and WLAN in an unlicensed band, the method being performed by a baseband unit (BBU) pool and the method includes: selecting a component carrier (CC) having a highest idle probability by considering an idle probability of the CC for the unlicensed band; determining the number NI of idle subframes in the selected CC by considering a residence time in a WLAN system queue; and allocating a resource block (RB) to an LTE user terminal in a cell based on the number of selected CCs and the number of idle subframes and which appropriately selects a resource in a frequency domain and a time domain in LTE to acquire high throughput and fairness in the LTE and the WLAN in the unlicensed band.

Abstract: A method for configuring a service function path (SFP) for a software defined network (SDN) based service function chain (SFC) may comprise configuring a SFC which is a set of ordered service functions (SFs) by reflecting requirements of a flow flowing into a network; generating a primary SFP that is a path through which the flow is to be actually transmitted in the network according to the SFC; generating a secondary SFP against an error of the primary SFP; and controlling a transmission path through which the flow is transmitted to be at least one of the primary SFP and the secondary SFP.

Abstract: A method of a Mobile Station (MS) for discovering neighbor MSs in a Device to Device (D2D) network includes broadcasting, by a discovery MS, a discovery request signal for discovering neighbor MSs, using a discovery request resource region repeated with a first period, if a neighbor MS discovery event is detected; and receiving, by the discovery MS, a discovery signal from at least one of other MSs in response to the discovery request signal, using a discovery resource region repeated with a second period. Other embodiments including a method for a central node discovering neighbor MSs and a discovery MS and a central node are also disclosed.

Abstract: There are provided an apparatus and a method for establishing a contention window in a WiMedia wireless network. The contention window establishing apparatus includes: a parsing unit extracting the number of devices that intend to transmit data from a beacon received during a beacon period and an access category (AC) of each device; a calculation unit calculating a transmission probability of each access category (AC) on the basis of the extracted number of devices; and a contention window establishing unit establishing a contention window for each access category (AC) on the basis of the calculated transmission probability, to reduce contentions among the devices and decrease data transmission latency time, thereby maximizing efficiency in data transmission latency time.

Abstract: A method includes continuously receiving N data frames encoded from K source data packets by an erasure coding method; checking for errors in the received N data frames; and transmitting an acknowledge (ACK) message informing that the source data packets are capable of being restored, when the number (R) of data frames not containing errors is equal to or greater than the number (K) of source data packets, and transmitting an ACK message including the number (X) of data frames for which retransmission is to be requested when the number (R) of data frames not containing errors is less than the number (K) of source data packets, as a result of the checking.

Abstract: A method of a Mobile Station (MS) for discovering neighbor MSs in a Device to Device (D2D) network includes broadcasting, by a discovery MS, a discovery request signal for discovering neighbor MSs, using a discovery request resource region repeated with a first period, if a neighbor MS discovery event is detected; and receiving, by the discovery MS, a discovery signal from at least one of other MSs in response to the discovery request signal, using a discovery resource region repeated with a second period. Other embodiments including a method for a central node discovering neighbor MSs and a discovery MS and a central node are also disclosed.

Abstract: There are provided an apparatus and a method for establishing a contention window in a WiMedia wireless network. The contention window establishing apparatus includes: a parsing unit extracting the number of devices that intend to transmit data from a beacon received during a beacon period and an access category (AC) of each device; a calculation unit calculating a transmission probability of each access category (AC) on the basis of the extracted number of devices; and a contention window establishing unit establishing a contention window for each access category (AC) on the basis of the calculated transmission probability, to reduce contentions among the devices and decrease data transmission latency time, thereby maximizing efficiency in data transmission latency time.

Abstract: There are provided an apparatus and a method for establishing a contention window in a WiMedia wireless network. The contention window establishing apparatus includes: a parsing unit extracting the number of devices that intend to transmit data from a beacon received during a beacon period and an access category (AC) of each device; a calculation unit calculating a transmission probability of each access category (AC) on the basis of the extracted number of devices; and a contention window establishing unit establishing a contention window for each access category (AC) on the basis of the calculated transmission probability, to reduce contentions among the devices and decrease data transmission latency time, thereby maximizing efficiency in data transmission latency time.

Abstract: A media access control method in a wireless network is provided. Each of devices in the wireless network determines one of a plurality of beacon slots within a beacon period as a beacon slot of the device. The devices in the wireless network determine a data transmission order in accordance with the slot numbers of the beacon slots of the devices in a reserved period of a data transmission period. Data is transmitted in the unreserved period in accordance with the determined data transmission order.

Abstract: There is provided a network apparatus capable of effectively retransmitting a frame in a frame aggregation environment, and a method of retransmitting a frame using the same. The network apparatus includes: a transmitting node broadcasting a plurality of data frames in a frame aggregation environment; a receiving node receiving the plurality of broadcast data frames and broadcasting a reception result; and at least one relay node receiving and storing at least a portion of the plurality of broadcast data frames and transmitting, together with the transmitting node, a data frame for which retransmission is required to the receiving node according to a calculated transmission success rate when the reception result from the receiving node is a retransmission request.

Abstract: A method of reducing a retransmission of a data frame and a receiving node therefor continuously receiving N data frames generated by encoding K source data packets by erasure coding. Errors in the received N data frames are checked, and an ACK message transmitted informing that the source data packets are capable of being restored, when the number (R) of data frames not containing errors is equal to or greater than the number (K) of source data packets. An ACK message including the number (X) of data frames for which retransmission is to be requested is transmitted when the number (R) of data frames not containing errors is less than the number (K) of source data packets, as a result of checking for errors in the received N data frames. Despite errors in some of the data frames, data may be restored without requesting the retransmission of data frames.

Abstract: There are provided an apparatus and a method for establishing a contention window in a WiMedia wireless network. The contention window establishing apparatus includes: a parsing unit extracting the number of devices that intend to transmit data from a beacon received during a beacon period and an access category (AC) of each device; a calculation unit calculating a transmission probability of each access category (AC) on the basis of the extracted number of devices; and a contention window establishing unit establishing a contention window for each access category (AC) on the basis of the calculated transmission probability, to reduce contentions among the devices and decrease data transmission latency time, thereby maximizing efficiency in data transmission latency time.

Abstract: A media access control method in a wireless network is provided. Each of devices in the wireless network determines one of a plurality of beacon slots within a beacon period as a beacon slot of the device. The devices in the wireless network determine a data transmission order in accordance with the slot numbers of the beacon slots of the devices in a reserved period of a data transmission period. Data is transmitted in the unreserved period in accordance with the determined data transmission order.