[Object] To provide a communication device and a communication method which are capable of achieving both an improvement in reliability of communication in which a frame is transmitted to a plurality of destinations and effective use of wireless communication resources.

[Solution] The communication device includes: a communication unit configured to perform communication of a frame. The communication unit transmits a transmission acknowledgment request frame for a transmission acknowledgment response frame including frequency allocation information specifying a transmission frequency of the transmission acknowledgment response frame, and receives the transmission acknowledgment response frame which has undergone frequency division multiplexing, on the basis of the frequency allocation information.

The invention relates to an improved transmission protocol for uplink data packet transmission in a communication system. A receiver of a user equipment receives a Fast Retransmission Indicator, referred to as FRI. The FRI indicates whether or not a base station requests a retransmission of a previously transmitted data packet. A transmitter of the user equipment retransmits the data packet using the same redundancy version as already used for the previous transmission of the data packet.

According to one aspect of the present disclosure, a system includes an active network element having circuitry for executing a primary application and a transmission control protocol (TCP) module, multiple standby network elements having circuitry for executing a secondary copy of the primary application and a secondary TCP module, and a network connection coupled to one or more of the active and standby network elements, wherein the active network element and standby network elements are coupled to transfer data and acknowledgments via their respective TCP modules, and wherein the standby network elements are reconfigurable to communicate via the network connection to a peer regardless of the failure of one or two of the network elements.

[Object] To provide a communication device and a communication method which are capable of achieving both an improvement in reliability of communication in which a frame is transmitted to a plurality of destinations and effective use of wireless communication resources. [Solution] The communication device includes: a communication unit configured to perform communication of a frame. The communication unit transmits a transmission acknowledgment request frame for a transmission acknowledgment response frame including frequency allocation information specifying a transmission frequency of the transmission acknowledgment response frame, and receives the transmission acknowledgment response frame which has undergone frequency division multiplexing, on the basis of the frequency allocation information.

According to one aspect of the present disclosure, a system includes an active network element having circuitry for executing a primary application and a transmission control protocol (TCP) module, multiple standby network elements having circuitry for executing a secondary copy of the primary application and a secondary TCP module, and a network connection coupled to one or more of the active and standby network elements, wherein the active network element and standby network elements are coupled to transfer data and acknowledgments via their respective TCP modules, and wherein the standby network elements are reconfigurable to communicate via the network connection to a peer regardless of the failure of one or two of the network elements.

Conventional protocols for live media streaming are not lightweight and hence not suitable for constrained video transmitting devices. The protocols are poor in terms of delay performance under lossy conditions and need to maintain a lot of states at the constrained transmitting end leading to load on the memory and draining energy of the devices. The conventionally used protocols do not perform well for intermittent connectivity. Usually the existing streaming solutions act either in completely reliable manner, using reliable transport protocol like TCP, or in completely unreliable manner using best effort unreliable transport protocol like UDP. The present disclosure provides a single streaming solution which can change the protocol semantics and maintains a balance between reliability and delay-performance, thereby optimizing the overall system goodput. The protocol does this intelligently by inferring the criticality of the segment in flight and enable live video streaming for Internet of Things (IoT).

Multicast messaging may be managed in a machine-to-machine/Internet of things context, such as a CoAP network, via the inclusion of server selection criterion in multicast request messages and/or resource directory registration management. Server selection criteria may be explicit or implicit. An explicit criterion may be expressed, for example, as an IP address, a server identifier relative to a group context, or a Bloom filter. An implicit criterion may, for example, relate to the context of the request or the requestor, and include such information as data accuracy, data type, application, operating system, network location, geolocation, resource creation time, and resource update time. Server selection criteria may be maintained by a resource directory and/or via a user interface.

According to one aspect of the present disclosure, a system includes an active network element having circuitry for executing a primary application and a transmission control protocol (TCP) module, multiple standby network elements having circuitry for executing a secondary copy of the primary application and a secondary TCP module, and a network connection coupled to one or more of the active and standby network elements, wherein the active network element and standby network elements are coupled to transfer data and acknowledgments via their respective TCP modules, and wherein the standby network elements are reconfigurable to communicate via the network connection to a peer regardless of the failure of one or two of the network elements.

A system and method for transmitting packets to a plurality of network devices that cannot be accessed via a single hop. The system includes a source, which issues a multicast message to those network devices in close proximity, and also transmits an encapsulated multicast message to a distribution node. This encapsulated multicast message may be routed using traditional routing protocols. The distribution node then transmits the multicast message to those network devices within close proximity. The distribution node may also have the ability to transmit singlecast messages to those network devices, if necessary, to perform retries.

[Object] To provide a mechanism capable of improving the efficiency of wireless communication even in a case in which the sequence numbers of received data units are non-sequential. [Solution] A wireless communication device including: a processing unit that generates a protocol data unit (PDU) that has sequence information with which a sequence number of a data unit that is determined as being to be resent is specified; and a communication unit that transmits the PDU generated by the processing unit. A wireless communication device including: a communication unit that receives a protocol data unit (PDU) that has sequence information with which a sequence number of a data unit that is determined as being to be resent is specified; and an acquisition unit that acquires the sequence information from the PDU received by the communication unit.