Nec Corporation

Tadayuki Oono

Takahiro Shiroshima

Takeo Onishi

Masahiro Kawato

Takaaki Kuroda

Masayuki Kayahara

In order to make it possible to suppress increase in the cost of message retransmission, this message delivery device delivers a message, stores a history relating to the success or failure of the delivery to each of destinations of the message in a history storage unit, when the delivery of the message has failed, determines on the basis of the history whether to perform retransmission of the message, and when determining to perform the retransmission, performs the retransmission of the message.

Message delivery device, Method, and recording medium

A terminal, a message distribution system, a message distribution method, and a message distribution program are provided, which are capable of reliably delivering a push message to the terminal from a push server, regardless of a type of network utilized by the terminal, while reducing a processing load of the push server. The terminal includes a network status detection unitwhich detects a status of a network connecting the terminal and a distribution device performing push-type message distribution, and a reception unitwhich determines, based on a result of the detection, whether the terminal and the distribution device are located in a same IP address space, selects, if the terminal and the distribution device are not located in the same IP address space, a first communication method utilizing a pre-established TCP session, selects, if the terminal and the distribution device are located in the same IP address space, a second communication method utilizing a TCP session between the distribution device and the terminal, which is newly established by the distribution device when a message is distributed, and receives a message from the distribution device.

Terminal, message distribution system, message distribution method, and computer-readable medium

Provided are a delivery device, a communication system, a load balancing method, and a load balancing program that enable processing loads for maintaining connections with terminals to be balanced over time, and enable the real time property of message delivery to be maintained for an event notification service. The delivery device is provided with: a communication unit () that transmits, to each terminal connected to the delivery device, a keepalive signal to maintain the connection between the delivery device and each terminal when there is no data to be delivered; and a transmission time determination unit () that divides a period in which the communication unit () transmits a keepalive signal into a plurality of time slots, calculates the expected number of transmissions of the keepalive signal for each time slot on the basis of keepalive signal interval information, which represents the interval of the keepalive signal for each terminal, and, if the expected number of transmissions exceeds a predefined threshold value, transmits, to the communication unit (), the keepalive signal for the portion exceeding the threshold value in the time slot prior to the time slot.

Delivery device, communication system, load balancing method, and load balancing program

An image sharing system includes: a server apparatus; first and second client apparatuses, which are communicably connected with the server apparatus; first and second telephone terminals associated with the first and second client apparatuses respectively; a connection control apparatus for controlling the connection between the first telephone terminal and the second telephone terminal; and a communication terminal including a camera part for photographing a subject, and an image sending part for sending image data representing the image outputted from the camera part, wherein the server apparatus includes a share-image sending part for sending an image represented by image data sent from the communication terminal as a share image to both the first and the second client apparatuses when the first telephone terminal is connected with the second telephone terminal, and both the first and the second client apparatuses include a share-image display part for displaying the share image.

Growing community of inventors

Tokyo, Japan

Tadayuki Oono