Abstract: A communication terminal apparatus including a second apparatus having a communication function and a first apparatus connectable to the second apparatus. The communication terminal apparatus includes an external communication function unit that is disposed in the second apparatus and acquires software, which is executable in the first apparatus, from an outside, a second memory that is disposed in the second apparatus and stores the software which is acquired, a first memory that is disposed in the first apparatus, and storage unit that is disposed in the first apparatus and stores the software read out from the second memory to the first memory according to a connection between the first apparatus and the second apparatus.

Abstract: A resilient packet network (RPR) device is connected to one or more rings to constitute an RPR network. The RPR device has a storage unit in which a correspondence between RPR device addresses, each indicating an RPR device connected to the one or more rings, and user device addresses, each indicating a user device accommodated in the RPR device, is stored. When the RPR device receives data addressed to a predetermined user device from a user device accommodated in the RPR device itself, if an RPR device address of an RPR device accommodating the predetermined user device is registered in the storage unit, an RPR header, in which the RPR device address is set as a destination RPR device address, is added to the data. The data with the RPR header is transmitted to the RPR network.

Abstract: Network load is reduced by combining packets by considering the MTU of a transmission path. When a routing processing unit detects the transmission of a large number of packets addressed to the same destination network, a routing information gathering unit determines the MTU of a transmission path along which the packets are to be transmitted. A combining unit assembles a combined packet by combining packets up to a length that does not exceed the MTU of the transmission path, and sends out the combined packet.

Abstract: A resilient packet network (RPR) device is connected to one or more rings to constitute an RPR network. The RPR device has a storage unit in which a correspondence between RPR device addresses, each indicating an RPR device connected to the one or more rings, and user device addresses, each indicating a user device accommodated in the RPR device, is stored. When the RPR device receives data addressed to a predetermined user device from a user device accommodated in the RPR device itself, if an RPR device address of an RPR device accommodating the predetermined user device is registered in the storage unit, an RPR header, in which the RPR device address is set as a destination RPR device address, is added to the data. The data with the RPR header is transmitted to the RPR network.

Abstract: An ATM cell compression recovery device includes an ATM cell recovery device having a compressed cell determination unit that determines whether an ATM cell from a transmission line is a compressed cell, a cell recovery unit that recovers the determined compressed cell in an ATM layer into an original ATM cell, and a switch that switches the recovered ATM cell. The ATM cell compression recovery device also includes a compression object cell determination unit that determines whether ATM cells received from the switch on an identified path have been compressed, and a compressed cell production unit that compresses the ATM cell in an ATM layer to be transmitted on the identified part. With this device, data is compressed and recovered in the ATM layer of the ATM network.

Abstract: Network load is reduced by combining packets by considering the MTU of a transmission path. When a routing processing unit detects the transmission of a large number of packets addressed to the same destination network, a routing information gathering unit determines the MTU of a transmission path along which the packets are to be transmitted. A combining unit assembles a combined packet by combining packets up to a length that does not exceed the MTU of the transmission path, and sends out the combined packet.

Abstract: Image data communicating apparatus and communication data quantity adjusting method in an image data communication system suitable for use when image data is transferred in a network environment. Image data is transferred in a most suitable quantity based on traffic of a network to avoid an effect on other services provided by the network. The apparatus has a data transmitting unit for transmitting image data to another image data communicating apparatus, a traffic detecting unit for detecting traffic of the network, and a communication data quantity adjusting unit for initially setting a transmittable number of image transferring frames on the basis of the detected traffic, and for automatically adjusting the quantity of data communication in the data transmitting unit on the basis of changing traffic on the network by altering the set number of frames.